cregit-Linux how code gets into the kernel

Release 4.10 fs/namespace.c

Directory: fs
/*
 *  linux/fs/namespace.c
 *
 * (C) Copyright Al Viro 2000, 2001
 *      Released under GPL v2.
 *
 * Based on code from fs/super.c, copyright Linus Torvalds and others.
 * Heavily rewritten.
 */

#include <linux/syscalls.h>
#include <linux/export.h>
#include <linux/capability.h>
#include <linux/mnt_namespace.h>
#include <linux/user_namespace.h>
#include <linux/namei.h>
#include <linux/security.h>
#include <linux/idr.h>
#include <linux/init.h>		/* init_rootfs */
#include <linux/fs_struct.h>	/* get_fs_root et.al. */
#include <linux/fsnotify.h>	/* fsnotify_vfsmount_delete */
#include <linux/uaccess.h>
#include <linux/proc_ns.h>
#include <linux/magic.h>
#include <linux/bootmem.h>
#include <linux/task_work.h>
#include "pnode.h"
#include "internal.h"

/* Maximum number of mounts in a mount namespace */

unsigned int sysctl_mount_max __read_mostly = 100000;


static unsigned int m_hash_mask __read_mostly;

static unsigned int m_hash_shift __read_mostly;

static unsigned int mp_hash_mask __read_mostly;

static unsigned int mp_hash_shift __read_mostly;


static __initdata unsigned long mhash_entries;

static int __init set_mhash_entries(char *str) { if (!str) return 0; mhash_entries = simple_strtoul(str, &str, 0); return 1; }

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al viroal viro34100.00%1100.00%
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__setup("mhash_entries=", set_mhash_entries); static __initdata unsigned long mphash_entries;
static int __init set_mphash_entries(char *str) { if (!str) return 0; mphash_entries = simple_strtoul(str, &str, 0); return 1; }

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__setup("mphash_entries=", set_mphash_entries); static u64 event; static DEFINE_IDA(mnt_id_ida); static DEFINE_IDA(mnt_group_ida); static DEFINE_SPINLOCK(mnt_id_lock); static int mnt_id_start = 0; static int mnt_group_start = 1; static struct hlist_head *mount_hashtable __read_mostly; static struct hlist_head *mountpoint_hashtable __read_mostly; static struct kmem_cache *mnt_cache __read_mostly; static DECLARE_RWSEM(namespace_sem); /* /sys/fs */ struct kobject *fs_kobj; EXPORT_SYMBOL_GPL(fs_kobj); /* * vfsmount lock may be taken for read to prevent changes to the * vfsmount hash, ie. during mountpoint lookups or walking back * up the tree. * * It should be taken for write in all cases where the vfsmount * tree or hash is modified or when a vfsmount structure is modified. */ __cacheline_aligned_in_smp DEFINE_SEQLOCK(mount_lock);
static inline struct hlist_head *m_hash(struct vfsmount *mnt, struct dentry *dentry) { unsigned long tmp = ((unsigned long)mnt / L1_CACHE_BYTES); tmp += ((unsigned long)dentry / L1_CACHE_BYTES); tmp = tmp + (tmp >> m_hash_shift); return &mount_hashtable[tmp & m_hash_mask]; }

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static inline struct hlist_head *mp_hash(struct dentry *dentry) { unsigned long tmp = ((unsigned long)dentry / L1_CACHE_BYTES); tmp = tmp + (tmp >> mp_hash_shift); return &mountpoint_hashtable[tmp & mp_hash_mask]; }

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al viroal viro4391.49%133.33%
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linus torvaldslinus torvalds24.26%133.33%
Total47100.00%3100.00%


static int mnt_alloc_id(struct mount *mnt) { int res; retry: ida_pre_get(&mnt_id_ida, GFP_KERNEL); spin_lock(&mnt_id_lock); res = ida_get_new_above(&mnt_id_ida, mnt_id_start, &mnt->mnt_id); if (!res) mnt_id_start = mnt->mnt_id + 1; spin_unlock(&mnt_id_lock); if (res == -EAGAIN) goto retry; return res; }

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miklos szeredimiklos szeredi5875.32%125.00%
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Total77100.00%4100.00%


static void mnt_free_id(struct mount *mnt) { int id = mnt->mnt_id; spin_lock(&mnt_id_lock); ida_remove(&mnt_id_ida, id); if (mnt_id_start > id) mnt_id_start = id; spin_unlock(&mnt_id_lock); }

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Total48100.00%4100.00%

/* * Allocate a new peer group ID * * mnt_group_ida is protected by namespace_sem */
static int mnt_alloc_group_id(struct mount *mnt) { int res; if (!ida_pre_get(&mnt_group_ida, GFP_KERNEL)) return -ENOMEM; res = ida_get_new_above(&mnt_group_ida, mnt_group_start, &mnt->mnt_group_id); if (!res) mnt_group_start = mnt->mnt_group_id + 1; return res; }

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miklos szeredimiklos szeredi3761.67%133.33%
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/* * Release a peer group ID */
void mnt_release_group_id(struct mount *mnt) { int id = mnt->mnt_group_id; ida_remove(&mnt_group_ida, id); if (mnt_group_start > id) mnt_group_start = id; mnt->mnt_group_id = 0; }

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miklos szeredimiklos szeredi2253.66%133.33%
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/* * vfsmount lock must be held for read */
static inline void mnt_add_count(struct mount *mnt, int n) { #ifdef CONFIG_SMP this_cpu_add(mnt->mnt_pcp->mnt_count, n); #else preempt_disable(); mnt->mnt_count += n; preempt_enable(); #endif }

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nick pigginnick piggin4497.78%150.00%
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/* * vfsmount lock must be held for write */
unsigned int mnt_get_count(struct mount *mnt) { #ifdef CONFIG_SMP unsigned int count = 0; int cpu; for_each_possible_cpu(cpu) { count += per_cpu_ptr(mnt->mnt_pcp, cpu)->mnt_count; } return count; #else return mnt->mnt_count; #endif }

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static void drop_mountpoint(struct fs_pin *p) { struct mount *m = container_of(p, struct mount, mnt_umount); dput(m->mnt_ex_mountpoint); pin_remove(p); mntput(&m->mnt); }

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static struct mount *alloc_vfsmnt(const char *name) { struct mount *mnt = kmem_cache_zalloc(mnt_cache, GFP_KERNEL); if (mnt) { int err; err = mnt_alloc_id(mnt); if (err) goto out_free_cache; if (name) { mnt->mnt_devname = kstrdup_const(name, GFP_KERNEL); if (!mnt->mnt_devname) goto out_free_id; } #ifdef CONFIG_SMP mnt->mnt_pcp = alloc_percpu(struct mnt_pcp); if (!mnt->mnt_pcp) goto out_free_devname; this_cpu_add(mnt->mnt_pcp->mnt_count, 1); #else mnt->mnt_count = 1; mnt->mnt_writers = 0; #endif INIT_HLIST_NODE(&mnt->mnt_hash); INIT_LIST_HEAD(&mnt->mnt_child); INIT_LIST_HEAD(&mnt->mnt_mounts); INIT_LIST_HEAD(&mnt->mnt_list); INIT_LIST_HEAD(&mnt->mnt_expire); INIT_LIST_HEAD(&mnt->mnt_share); INIT_LIST_HEAD(&mnt->mnt_slave_list); INIT_LIST_HEAD(&mnt->mnt_slave); INIT_HLIST_NODE(&mnt->mnt_mp_list); #ifdef CONFIG_FSNOTIFY INIT_HLIST_HEAD(&mnt->mnt_fsnotify_marks); #endif init_fs_pin(&mnt->mnt_umount, drop_mountpoint); } return mnt; #ifdef CONFIG_SMP out_free_devname: kfree_const(mnt->mnt_devname); #endif out_free_id: mnt_free_id(mnt); out_free_cache: kmem_cache_free(mnt_cache, mnt); return NULL; }

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nick pigginnick piggin6123.83%28.70%
linus torvaldslinus torvalds5521.48%28.70%
al viroal viro4015.62%730.43%
li zefanli zefan238.98%14.35%
ram pairam pai218.20%28.70%
miklos szeredimiklos szeredi207.81%28.70%
andreas gruenbacherandreas gruenbacher135.08%14.35%
eric w. biedermaneric w. biederman83.12%14.35%
david howellsdavid howells62.34%14.35%
dave hansendave hansen51.95%14.35%
andrzej hajdaandrzej hajda20.78%14.35%
andries brouwerandries brouwer10.39%14.35%
robert p. j. dayrobert p. j. day10.39%14.35%
Total256100.00%23100.00%

/* * Most r/o checks on a fs are for operations that take * discrete amounts of time, like a write() or unlink(). * We must keep track of when those operations start * (for permission checks) and when they end, so that * we can determine when writes are able to occur to * a filesystem. */ /* * __mnt_is_readonly: check whether a mount is read-only * @mnt: the mount to check for its write status * * This shouldn't be used directly ouside of the VFS. * It does not guarantee that the filesystem will stay * r/w, just that it is right *now*. This can not and * should not be used in place of IS_RDONLY(inode). * mnt_want/drop_write() will _keep_ the filesystem * r/w. */
int __mnt_is_readonly(struct vfsmount *mnt) { if (mnt->mnt_flags & MNT_READONLY) return 1; if (mnt->mnt_sb->s_flags & MS_RDONLY) return 1; return 0; }

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dave hansendave hansen37100.00%2100.00%
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EXPORT_SYMBOL_GPL(__mnt_is_readonly);
static inline void mnt_inc_writers(struct mount *mnt) { #ifdef CONFIG_SMP this_cpu_inc(mnt->mnt_pcp->mnt_writers); #else mnt->mnt_writers++; #endif }

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dave hansendave hansen1648.48%120.00%
nick pigginnick piggin1648.48%360.00%
al viroal viro13.03%120.00%
Total33100.00%5100.00%


static inline void mnt_dec_writers(struct mount *mnt) { #ifdef CONFIG_SMP this_cpu_dec(mnt->mnt_pcp->mnt_writers); #else mnt->mnt_writers--; #endif }

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al viroal viro13.03%120.00%
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static unsigned int mnt_get_writers(struct mount *mnt) { #ifdef CONFIG_SMP unsigned int count = 0; int cpu; for_each_possible_cpu(cpu) { count += per_cpu_ptr(mnt->mnt_pcp, cpu)->mnt_writers; } return count; #else return mnt->mnt_writers; #endif }

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nick pigginnick piggin3054.55%360.00%
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al viroal viro11.82%120.00%
Total55100.00%5100.00%


static int mnt_is_readonly(struct vfsmount *mnt) { if (mnt->mnt_sb->s_readonly_remount) return 1; /* Order wrt setting s_flags/s_readonly_remount in do_remount() */ smp_rmb(); return __mnt_is_readonly(mnt); }

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miklos szeredimiklos szeredi32100.00%1100.00%
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/* * Most r/o & frozen checks on a fs are for operations that take discrete * amounts of time, like a write() or unlink(). We must keep track of when * those operations start (for permission checks) and when they end, so that we * can determine when writes are able to occur to a filesystem. */ /** * __mnt_want_write - get write access to a mount without freeze protection * @m: the mount on which to take a write * * This tells the low-level filesystem that a write is about to be performed to * it, and makes sure that writes are allowed (mnt it read-write) before * returning success. This operation does not protect against filesystem being * frozen. When the write operation is finished, __mnt_drop_write() must be * called. This is effectively a refcount. */
int __mnt_want_write(struct vfsmount *m) { struct mount *mnt = real_mount(m); int ret = 0; preempt_disable(); mnt_inc_writers(mnt); /* * The store to mnt_inc_writers must be visible before we pass * MNT_WRITE_HOLD loop below, so that the slowpath can see our * incremented count after it has set MNT_WRITE_HOLD. */ smp_mb(); while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) cpu_relax(); /* * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will * be set to match its requirements. So we must not load that until * MNT_WRITE_HOLD is cleared. */ smp_rmb(); if (mnt_is_readonly(m)) { mnt_dec_writers(mnt); ret = -EROFS; } preempt_enable(); return ret; }

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nick pigginnick piggin3947.56%225.00%
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miao xiemiao xie33.66%112.50%
jan karajan kara11.22%112.50%
miklos szeredimiklos szeredi11.22%112.50%
Total82100.00%8100.00%

/** * mnt_want_write - get write access to a mount * @m: the mount on which to take a write * * This tells the low-level filesystem that a write is about to be performed to * it, and makes sure that writes are allowed (mount is read-write, filesystem * is not frozen) before returning success. When the write operation is * finished, mnt_drop_write() must be called. This is effectively a refcount. */
int mnt_want_write(struct vfsmount *m) { int ret; sb_start_write(m->mnt_sb); ret = __mnt_want_write(m); if (ret) sb_end_write(m->mnt_sb); return ret; }

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jan karajan kara41100.00%1100.00%
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EXPORT_SYMBOL_GPL(mnt_want_write); /** * mnt_clone_write - get write access to a mount * @mnt: the mount on which to take a write * * This is effectively like mnt_want_write, except * it must only be used to take an extra write reference * on a mountpoint that we already know has a write reference * on it. This allows some optimisation. * * After finished, mnt_drop_write must be called as usual to * drop the reference. */
int mnt_clone_write(struct vfsmount *mnt) { /* superblock may be r/o */ if (__mnt_is_readonly(mnt)) return -EROFS; preempt_disable(); mnt_inc_writers(real_mount(mnt)); preempt_enable(); return 0; }

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EXPORT_SYMBOL_GPL(mnt_clone_write); /** * __mnt_want_write_file - get write access to a file's mount * @file: the file who's mount on which to take a write * * This is like __mnt_want_write, but it takes a file and can * do some optimisations if the file is open for write already */
int __mnt_want_write_file(struct file *file) { if (!(file->f_mode & FMODE_WRITER)) return __mnt_want_write(file->f_path.mnt); else return mnt_clone_write(file->f_path.mnt); }

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nick pigginnick piggin3992.86%133.33%
jan karajan kara24.76%133.33%
al viroal viro12.38%133.33%
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/** * mnt_want_write_file - get write access to a file's mount * @file: the file who's mount on which to take a write * * This is like mnt_want_write, but it takes a file and can * do some optimisations if the file is open for write already */
int mnt_want_write_file(struct file *file) { int ret; sb_start_write(file->f_path.mnt->mnt_sb); ret = __mnt_want_write_file(file); if (ret) sb_end_write(file->f_path.mnt->mnt_sb); return ret; }

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jan karajan kara49100.00%1100.00%
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EXPORT_SYMBOL_GPL(mnt_want_write_file); /** * __mnt_drop_write - give up write access to a mount * @mnt: the mount on which to give up write access * * Tells the low-level filesystem that we are done * performing writes to it. Must be matched with * __mnt_want_write() call above. */
void __mnt_drop_write(struct vfsmount *mnt) { preempt_disable(); mnt_dec_writers(real_mount(mnt)); preempt_enable(); }

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jan karajan kara14.17%120.00%
Total24100.00%5100.00%

/** * mnt_drop_write - give up write access to a mount * @mnt: the mount on which to give up write access * * Tells the low-level filesystem that we are done performing writes to it and * also allows filesystem to be frozen again. Must be matched with * mnt_want_write() call above. */
void mnt_drop_write(struct vfsmount *mnt) { __mnt_drop_write(mnt); sb_end_write(mnt->mnt_sb); }

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EXPORT_SYMBOL_GPL(mnt_drop_write);
void __mnt_drop_write_file(struct file *file) { __mnt_drop_write(file->f_path.mnt); }

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void mnt_drop_write_file(struct file *file) { mnt_drop_write(file->f_path.mnt); }

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EXPORT_SYMBOL(mnt_drop_write_file);
static int mnt_make_readonly(struct mount *mnt) { int ret = 0; lock_mount_hash(); mnt->mnt.mnt_flags |= MNT_WRITE_HOLD; /* * After storing MNT_WRITE_HOLD, we'll read the counters. This store * should be visible before we do. */ smp_mb(); /* * With writers on hold, if this value is zero, then there are * definitely no active writers (although held writers may subsequently * increment the count, they'll have to wait, and decrement it after * seeing MNT_READONLY). * * It is OK to have counter incremented on one CPU and decremented on * another: the sum will add up correctly. The danger would be when we * sum up each counter, if we read a counter before it is incremented, * but then read another CPU's count which it has been subsequently * decremented from -- we would see more decrements than we should. * MNT_WRITE_HOLD protects against this scenario, because * mnt_want_write first increments count, then smp_mb, then spins on * MNT_WRITE_HOLD, so it can't be decremented by another CPU while * we're counting up here. */ if (mnt_get_writers(mnt) > 0) ret = -EBUSY; else mnt->mnt.mnt_flags |= MNT_READONLY; /* * MNT_READONLY must become visible before ~MNT_WRITE_HOLD, so writers * that become unheld will see MNT_READONLY. */ smp_wmb(); mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD; unlock_mount_hash(); return ret; }

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al viroal viro1114.86%228.57%
Total74100.00%7100.00%


static void __mnt_unmake_readonly(struct mount *mnt) { lock_mount_hash(); mnt->mnt.mnt_flags &= ~MNT_READONLY; unlock_mount_hash(); }

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dave hansendave hansen1973.08%133.33%
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Total26100.00%3100.00%


int sb_prepare_remount_readonly(struct super_block *sb) { struct mount *mnt; int err = 0; /* Racy optimization. Recheck the counter under MNT_WRITE_HOLD */ if (atomic_long_read(&sb->s_remove_count)) return -EBUSY; lock_mount_hash(); list_for_each_entry(mnt, &sb->s_mounts, mnt_instance) { if (!(mnt->mnt.mnt_flags & MNT_READONLY)) { mnt->mnt.mnt_flags |= MNT_WRITE_HOLD; smp_mb(); if (mnt_get_writers(mnt) > 0) { err = -EBUSY; break; } } } if (!err && atomic_long_read(&sb->s_remove_count)) err = -EBUSY; if (!err) { sb->s_readonly_remount = 1; smp_wmb(); } list_for_each_entry(mnt, &sb->s_mounts, mnt_instance) { if (mnt->mnt.mnt_flags & MNT_WRITE_HOLD) mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD; } unlock_mount_hash(); return err; }

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miklos szeredimiklos szeredi15697.50%266.67%
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static void free_vfsmnt(struct mount *mnt) { kfree_const(mnt->mnt_devname); #ifdef CONFIG_SMP free_percpu(mnt->mnt_pcp); #endif kmem_cache_free(mnt_cache, mnt); }

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linus torvaldslinus torvalds2156.76%116.67%
nick pigginnick piggin1232.43%233.33%
al viroal viro38.11%233.33%
andrzej hajdaandrzej hajda12.70%116.67%
Total37100.00%6100.00%


static void delayed_free_vfsmnt(struct rcu_head *head) { free_vfsmnt(container_of(head, struct mount, mnt_rcu)); }

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david howellsdavid howells24100.00%1100.00%
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/* call under rcu_read_lock */
int __legitimize_mnt(struct vfsmount *bastard, unsigned seq) { struct mount *mnt; if (read_seqretry(&mount_lock, seq)) return 1; if (bastard == NULL) return 0; mnt = real_mount(bastard); mnt_add_count(mnt, 1); if (likely(!read_seqretry(&mount_lock, seq))) return 0; if (bastard->mnt_flags & MNT_SYNC_UMOUNT) { mnt_add_count(mnt, -1); return 1; } return -1; }

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al viroal viro96100.00%2100.00%
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/* call under rcu_read_lock */
bool legitimize_mnt(struct vfsmount *bastard, unsigned seq) { int res = __legitimize_mnt(bastard, seq); if (likely(!res)) return true; if (unlikely(res < 0)) { rcu_read_unlock(); mntput(bastard); rcu_read_lock(); } return false; }

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al viroal viro59100.00%2100.00%
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/* * find the first mount at @dentry on vfsmount @mnt. * call under rcu_read_lock() */
struct mount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry) { struct hlist_head *head = m_hash(mnt, dentry); struct mount *p; hlist_for_each_entry_rcu(p, head, mnt_hash) if (&p->mnt_parent->mnt == mnt && p->mnt_mountpoint == dentry) return p; return NULL; }

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linus torvaldslinus torvalds3350.77%116.67%
al viroal viro3046.15%466.67%
ram pairam pai23.08%116.67%
Total65100.00%6100.00%

/* * find the last mount at @dentry on vfsmount @mnt. * mount_lock must be held. */
struct mount *__lookup_mnt_last(struct vfsmount *mnt, struct dentry *dentry) { struct mount *p, *res = NULL; p = __lookup_mnt(mnt, dentry); if (!p) goto out; if (!(p->mnt.mnt_flags & MNT_UMOUNT)) res = p; hlist_for_each_entry_continue(p, mnt_hash) { if (&p->mnt_parent->mnt != mnt || p->mnt_mountpoint != dentry) break; if (!(p->mnt.mnt_flags & MNT_UMOUNT)) res = p; } out: return res; }

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al viroal viro6963.30%457.14%
eric w. biedermaneric w. biederman3229.36%114.29%
linus torvaldslinus torvalds54.59%114.29%
ram pairam pai32.75%114.29%
Total109100.00%7100.00%

/* * lookup_mnt - Return the first child mount mounted at path * * "First" means first mounted chronologically. If you create the * following mounts: * * mount /dev/sda1 /mnt * mount /dev/sda2 /mnt * mount /dev/sda3 /mnt * * Then lookup_mnt() on the base /mnt dentry in the root mount will * return successively the root dentry and vfsmount of /dev/sda1, then * /dev/sda2, then /dev/sda3, then NULL. * * lookup_mnt takes a reference to the found vfsmount. */
struct vfsmount *lookup_mnt(const struct path *path) { struct mount *child_mnt; struct vfsmount *m; unsigned seq; rcu_read_lock(); do { seq = read_seqbegin(&mount_lock); child_mnt = __lookup_mnt(path->mnt, path->dentry); m = child_mnt ? &child_mnt->mnt : NULL; } while (!legitimize_mnt(m, seq)); rcu_read_unlock(); return m; }

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al viroal viro5264.20%457.14%
ram pairam pai2632.10%114.29%
linus torvaldslinus torvalds22.47%114.29%
andi kleenandi kleen11.23%114.29%
Total81100.00%7100.00%

/* * __is_local_mountpoint - Test to see if dentry is a mountpoint in the * current mount namespace. * * The common case is dentries are not mountpoints at all and that * test is handled inline. For the slow case when we are actually * dealing with a mountpoint of some kind, walk through all of the * mounts in the current mount namespace and test to see if the dentry * is a mountpoint. * * The mount_hashtable is not usable in the context because we * need to identify all mounts that may be in the current mount * namespace not just a mount that happens to have some specified * parent mount. */
bool __is_local_mountpoint(struct dentry *dentry) { struct mnt_namespace *ns = current->nsproxy->mnt_ns; struct mount *mnt; bool is_covered = false; if (!d_mountpoint(dentry)) goto out; down_read(&namespace_sem); list_for_each_entry(mnt, &ns->list, mnt_list) { is_covered = (mnt->mnt_mountpoint == dentry); if (is_covered) break; } up_read(&namespace_sem); out: return is_covered; }

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eric w. biedermaneric w. biederman84100.00%1100.00%
Total84100.00%1100.00%


static struct mountpoint *lookup_mountpoint(struct dentry *dentry) { struct hlist_head *chain = mp_hash(dentry); struct mountpoint *mp; hlist_for_each_entry(mp, chain, m_hash) { if (mp->m_dentry == dentry) { /* might be worth a WARN_ON() */ if (d_unlinked(dentry)) return ERR_PTR(-ENOENT); mp->m_count++; return mp; } } return NULL; }

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al viroal viro6993.24%266.67%
eric w. biedermaneric w. biederman56.76%133.33%
Total74100.00%3100.00%


static struct mountpoint *get_mountpoint(struct dentry *dentry) { struct mountpoint *mp, *new = NULL; int ret; if (d_mountpoint(dentry)) { mountpoint: read_seqlock_excl(&mount_lock); mp = lookup_mountpoint(dentry); read_sequnlock_excl(&mount_lock); if (mp) goto done; } if (!new) new = kmalloc(sizeof(struct mountpoint), GFP_KERNEL); if (!new) return ERR_PTR(-ENOMEM); /* Exactly one processes may set d_mounted */ ret = d_set_mounted(dentry); /* Someone else set d_mounted? */ if (ret == -EBUSY) goto mountpoint; /* The dentry is not available as a mountpoint? */ mp = ERR_PTR(ret); if (ret) goto done; /* Add the new mountpoint to the hash table */ read_seqlock_excl(&mount_lock); new->m_dentry = dentry; new->m_count = 1; hlist_add_head(&new->m_hash, mp_hash(dentry)); INIT_HLIST_HEAD(&new->m_list); read_sequnlock_excl(&mount_lock); mp = new; new = NULL; done: kfree(new); return mp; }

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eric w. biedermaneric w. biederman12967.54%350.00%
al viroal viro5729.84%233.33%
miklos szeredimiklos szeredi52.62%116.67%
Total191100.00%6100.00%


static void put_mountpoint(struct mountpoint *mp) { if (!--mp->m_count) { struct dentry *dentry = mp->m_dentry; BUG_ON(!hlist_empty(&mp->m_list)); spin_lock(&dentry->d_lock); dentry->d_flags &= ~DCACHE_MOUNTED; spin_unlock(&dentry->d_lock); hlist_del(&mp->m_hash); kfree(mp); } }

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al viroal viro6684.62%266.67%
eric w. biedermaneric w. biederman1215.38%133.33%
Total78100.00%3100.00%


static inline int check_mnt(struct mount *mnt) { return mnt->mnt_ns == current->nsproxy->mnt_ns; }

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linus torvaldslinus torvalds1669.57%233.33%
david howellsdavid howells28.70%116.67%
kirill korotaevkirill korotaev28.70%116.67%
serge hallynserge hallyn28.70%116.67%
al viroal viro14.35%116.67%
Total23100.00%6100.00%

/* * vfsmount lock must be held for write */
static void touch_mnt_namespace(struct mnt_namespace *ns) { if (ns) { ns->event = ++event; wake_up_interruptible(&ns->poll); } }

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al viroal viro3093.75%150.00%
kirill korotaevkirill korotaev26.25%150.00%
Total32100.00%2100.00%

/* * vfsmount lock must be held for write */
static void __touch_mnt_namespace(struct mnt_namespace *ns) { if (ns && ns->event != event) { ns->event = event; wake_up_interruptible(&ns->poll); } }

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al viroal viro3594.59%150.00%
kirill korotaevkirill korotaev25.41%150.00%
Total37100.00%2100.00%

/* * vfsmount lock must be held for write */
static void unhash_mnt(struct mount *mnt) { mnt->mnt_parent = mnt; mnt->mnt_mountpoint = mnt->mnt.mnt_root; list_del_init(&mnt->mnt_child); hlist_del_init_rcu(&mnt->mnt_hash); hlist_del_init(&mnt->mnt_mp_list); put_mountpoint(mnt->mnt_mp); mnt->mnt_mp = NULL; }

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linus torvaldslinus torvalds3351.56%114.29%
al viroal viro1320.31%342.86%
nick pigginnick piggin914.06%114.29%
eric w. biedermaneric w. biederman914.06%228.57%
Total64100.00%7100.00%

/* * vfsmount lock must be held for write */
static void detach_mnt(struct mount *mnt, struct path *old_path) { old_path->dentry = mnt->mnt_mountpoint; old_path->mnt = &mnt->mnt_parent->mnt; unhash_mnt(mnt); }

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eric w. biedermaneric w. biederman40100.00%1100.00%
Total40100.00%1100.00%

/* * vfsmount lock must be held for write */
static void umount_mnt(struct mount *mnt) { /* old mountpoint will be dropped when we can do that */ mnt->mnt_ex_mountpoint = mnt->mnt_mountpoint; unhash_mnt(mnt); }

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eric w. biedermaneric w. biederman25100.00%1100.00%
Total25100.00%1100.00%

/* * vfsmount lock must be held for write */
void mnt_set_mountpoint(struct mount *mnt, struct mountpoint *mp, struct mount *child_mnt) { mp->m_count++; mnt_add_count(mnt, 1); /* essentially, that's mntget */ child_mnt->mnt_mountpoint = dget(mp->m_dentry); child_mnt->mnt_parent = mnt; child_mnt->mnt_mp = mp; hlist_add_head(&child_mnt->mnt_mp_list, &mp->m_list); }

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al viroal viro2739.13%555.56%
linus torvaldslinus torvalds1826.09%111.11%
eric w. biedermaneric w. biederman1318.84%111.11%
ram pairam pai1014.49%111.11%
nick pigginnick piggin11.45%111.11%
Total69100.00%9100.00%

/* * vfsmount lock must be held for write */
static void attach_mnt(struct mount *mnt, struct mount *parent, struct mountpoint *mp) { mnt_set_mountpoint(parent, mp, mnt); hlist_add_head_rcu(&mnt->mnt_hash, m_hash(&parent->mnt, mp->m_dentry)); list_add_tail(&mnt->mnt_child, &parent->mnt_mounts); }

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linus torvaldslinus torvalds2539.68%112.50%
al viroal viro2031.75%675.00%
ram pairam pai1828.57%112.50%
Total63100.00%8100.00%


static void attach_shadowed(struct mount *mnt, struct mount *parent, struct mount *shadows) { if (shadows) { hlist_add_behind_rcu(&mnt->mnt_hash, &shadows->mnt_hash); list_add(&mnt->mnt_child, &shadows->mnt_child); } else { hlist_add_head_rcu(&mnt->mnt_hash, m_hash(&parent->mnt, mnt->mnt_mountpoint)); list_add_tail(&mnt->mnt_child, &parent->mnt_mounts); } }

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al viroal viro8696.63%150.00%
linus torvaldslinus torvalds33.37%150.00%
Total89100.00%2100.00%

/* * vfsmount lock must be held for write */
static void commit_tree(struct mount *mnt, struct mount *shadows) { struct mount *parent = mnt->mnt_parent; struct mount *m; LIST_HEAD(head); struct mnt_namespace *n = parent->mnt_ns; BUG_ON(parent == mnt); list_add_tail(&head, &mnt->mnt_list); list_for_each_entry(m, &head, mnt_list) m->mnt_ns = n; list_splice(&head, n->list.prev); n->mounts += n->pending_mounts; n->pending_mounts = 0; attach_shadowed(mnt, parent, shadows); touch_mnt_namespace(n); }

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ram pairam pai8068.97%19.09%
eric w. biedermaneric w. biederman1412.07%19.09%
al viroal viro1311.21%654.55%
linus torvaldslinus torvalds43.45%19.09%
kirill korotaevkirill korotaev43.45%19.09%
ken heliasken helias10.86%19.09%
Total116100.00%11100.00%


static struct mount *next_mnt(struct mount *p, struct mount *root) { struct list_head *next = p->mnt_mounts.next; if (next == &p->mnt_mounts) { while (1) { if (p == root) return NULL; next = p->mnt_child.next; if (next != &p->mnt_parent->mnt_mounts) break; p = p->mnt_parent; } } return list_entry(next, struct mount, mnt_child); }

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linus torvaldslinus torvalds8895.65%133.33%
al viroal viro44.35%266.67%
Total92100.00%3100.00%


static struct mount *skip_mnt_tree(struct mount *p) { struct list_head *prev = p->mnt_mounts.prev; while (prev != &p->mnt_mounts) { p = list_entry(prev, struct mount, mnt_child); prev = p->mnt_mounts.prev; } return p; }

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ram pairam pai5594.83%150.00%
al viroal viro35.17%150.00%
Total58100.00%2100.00%


struct vfsmount * vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void *data) { struct mount *mnt; struct dentry *root; if (!type) return ERR_PTR(-ENODEV); mnt = alloc_vfsmnt(name); if (!mnt) return ERR_PTR(-ENOMEM); if (flags & MS_KERNMOUNT) mnt->mnt.mnt_flags = MNT_INTERNAL; root = mount_fs(type, flags, name, data); if (IS_ERR(root)) { mnt_free_id(mnt); free_vfsmnt(mnt); return ERR_CAST(root); } mnt->mnt.mnt_root = root; mnt->mnt.mnt_sb = root->d_sb; mnt->mnt_mountpoint = mnt->mnt.mnt_root; mnt->mnt_parent = mnt; lock_mount_hash(); list_add_tail(&mnt->mnt_instance, &root->d_sb->s_mounts); unlock_mount_hash(); return &mnt->mnt; }

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al viroal viro15687.64%360.00%
miklos szeredimiklos szeredi179.55%120.00%
david howellsdavid howells52.81%120.00%
Total178100.00%5100.00%

EXPORT_SYMBOL_GPL(vfs_kern_mount);
static struct mount *clone_mnt(struct mount *old, struct dentry *root, int flag) { struct super_block *sb = old->mnt.mnt_sb; struct mount *mnt; int err; mnt = alloc_vfsmnt(old->mnt_devname); if (!mnt) return ERR_PTR(-ENOMEM); if (flag & (CL_SLAVE | CL_PRIVATE | CL_SHARED_TO_SLAVE)) mnt->mnt_group_id = 0; /* not a peer of original */ else mnt->mnt_group_id = old->mnt_group_id; if ((flag & CL_MAKE_SHARED) && !mnt->mnt_group_id) { err = mnt_alloc_group_id(mnt); if (err) goto out_free; } mnt->mnt.mnt_flags = old->mnt.mnt_flags & ~(MNT_WRITE_HOLD|MNT_MARKED); /* Don't allow unprivileged users to change mount flags */ if (flag & CL_UNPRIVILEGED) { mnt->mnt.mnt_flags |= MNT_LOCK_ATIME; if (mnt->mnt.mnt_flags & MNT_READONLY) mnt->mnt.mnt_flags |= MNT_LOCK_READONLY; if (mnt->mnt.mnt_flags & MNT_NODEV) mnt->mnt.mnt_flags |= MNT_LOCK_NODEV; if (mnt->mnt.mnt_flags & MNT_NOSUID) mnt->mnt.mnt_flags |= MNT_LOCK_NOSUID; if (mnt->mnt.mnt_flags & MNT_NOEXEC) mnt->mnt.mnt_flags |= MNT_LOCK_NOEXEC; } /* Don't allow unprivileged users to reveal what is under a mount */ if ((flag & CL_UNPRIVILEGED) && (!(flag & CL_EXPIRE) || list_empty(&old->mnt_expire))) mnt->mnt.mnt_flags |= MNT_LOCKED; atomic_inc(&sb->s_active); mnt->mnt.mnt_sb = sb; mnt->mnt.mnt_root = dget(root); mnt->mnt_mountpoint = mnt->mnt.mnt_root; mnt->mnt_parent = mnt; lock_mount_hash(); list_add_tail(&mnt->mnt_instance, &sb->s_mounts); unlock_mount_hash(); if ((flag & CL_SLAVE) || ((flag & CL_SHARED_TO_SLAVE) && IS_MNT_SHARED(old))) { list_add(&mnt->mnt_slave, &old->mnt_slave_list); mnt->mnt_master = old; CLEAR_MNT_SHARED(mnt); } else if (!(flag & CL_PRIVATE)) { if ((flag & CL_MAKE_SHARED) || IS_MNT_SHARED(old)) list_add(&mnt->mnt_share, &old->mnt_share); if (IS_MNT_SLAVE(old)) list_add(&mnt->mnt_slave, &old->mnt_slave); mnt->mnt_master = old->mnt_master; } else { CLEAR_MNT_SHARED(mnt); } if (flag & CL_MAKE_SHARED) set_mnt_shared(mnt); /* stick the duplicate mount on the same expiry list * as the original if that was on one */ if (flag & CL_EXPIRE) { if (!list_empty(&old->mnt_expire)) list_add(&mnt->mnt_expire, &old->mnt_expire); } return mnt; out_free: mnt_free_id(mnt); free_vfsmnt(mnt); return ERR_PTR(err); }

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eric w. biedermaneric w. biederman14027.56%518.52%
ram pairam pai10420.47%311.11%
linus torvaldslinus torvalds8516.73%311.11%
miklos szeredimiklos szeredi7414.57%414.81%
david howellsdavid howells5210.24%311.11%
al viroal viro428.27%829.63%
nick pigginnick piggin112.17%13.70%
Total508100.00%27100.00%


static void cleanup_mnt(struct mount *mnt) { /* * This probably indicates that somebody messed * up a mnt_want/drop_write() pair. If this * happens, the filesystem was probably unable * to make r/w->r/o transitions. */ /* * The locking used to deal with mnt_count decrement provides barriers, * so mnt_get_writers() below is safe. */ WARN_ON(mnt_get_writers(mnt)); if (unlikely(mnt->mnt_pins.first)) mnt_pin_kill(mnt); fsnotify_vfsmount_delete(&mnt->mnt); dput(mnt->mnt.mnt_root); deactivate_super(mnt->mnt.mnt_sb); mnt_free_id(mnt); call_rcu(&mnt->mnt_rcu, delayed_free_vfsmnt); }

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al viroal viro78100.00%1100.00%
Total78100.00%1100.00%


static void __cleanup_mnt(struct rcu_head *head) { cleanup_mnt(container_of(head, struct mount, mnt_rcu)); }

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al viroal viro24100.00%1100.00%
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static LLIST_HEAD(delayed_mntput_list);
static void delayed_mntput(struct work_struct *unused) { struct llist_node *node = llist_del_all(&delayed_mntput_list); struct llist_node *next; for (; node; node = next) { next = llist_next(node); cleanup_mnt(llist_entry(node, struct mount, mnt_llist)); } }

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al viroal viro58100.00%1100.00%
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static DECLARE_DELAYED_WORK(delayed_mntput_work, delayed_mntput);
static void mntput_no_expire(struct mount *mnt) { rcu_read_lock(); mnt_add_count(mnt, -1); if (likely(mnt->mnt_ns)) { /* shouldn't be the last one */ rcu_read_unlock(); return; } lock_mount_hash(); if (mnt_get_count(mnt)) { rcu_read_unlock(); unlock_mount_hash(); return; } if (unlikely(mnt->mnt.mnt_flags & MNT_DOOMED)) { rcu_read_unlock(); unlock_mount_hash(); return; } mnt->mnt.mnt_flags |= MNT_DOOMED; rcu_read_unlock(); list_del(&mnt->mnt_instance); if (unlikely(!list_empty(&mnt->mnt_mounts))) { struct mount *p, *tmp; list_for_each_entry_safe(p, tmp, &mnt->mnt_mounts, mnt_child) { umount_mnt(p); } } unlock_mount_hash(); if (likely(!(mnt->mnt.mnt_flags & MNT_INTERNAL))) { struct task_struct *task = current; if (likely(!(task->flags & PF_KTHREAD))) { init_task_work(&mnt->mnt_rcu, __cleanup_mnt); if (!task_work_add(task, &mnt->mnt_rcu, true)) return; } if (llist_add(&mnt->mnt_llist, &delayed_mntput_list)) schedule_delayed_work(&delayed_mntput_work, 1); return; } cleanup_mnt(mnt); }

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al viroal viro15163.98%666.67%
eric w. biedermaneric w. biederman4117.37%111.11%
nick pigginnick piggin3615.25%111.11%
miklos szeredimiklos szeredi83.39%111.11%
Total236100.00%9100.00%


void mntput(struct vfsmount *mnt) { if (mnt) { struct mount *m = real_mount(mnt); /* avoid cacheline pingpong, hope gcc doesn't get "smart" */ if (unlikely(m->mnt_expiry_mark)) m->mnt_expiry_mark = 0; mntput_no_expire(m); } }

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nick pigginnick piggin1736.17%114.29%
al viroal viro1531.91%342.86%
linus torvaldslinus torvalds1225.53%114.29%
andreas gruenbacherandreas gruenbacher24.26%114.29%
dave hansendave hansen12.13%114.29%
Total47100.00%7100.00%

EXPORT_SYMBOL(mntput);
struct vfsmount *mntget(struct vfsmount *mnt) { if (mnt) mnt_add_count(real_mount(mnt), 1); return mnt; }

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al viroal viro1758.62%360.00%
nick pigginnick piggin1241.38%240.00%
Total29100.00%5100.00%

EXPORT_SYMBOL(mntget); /* path_is_mountpoint() - Check if path is a mount in the current * namespace. * * d_mountpoint() can only be used reliably to establish if a dentry is * not mounted in any namespace and that common case is handled inline. * d_mountpoint() isn't aware of the possibility there may be multiple * mounts using a given dentry in a different namespace. This function * checks if the passed in path is a mountpoint rather than the dentry * alone. */
bool path_is_mountpoint(const struct path *path) { unsigned seq; bool res; if (!d_mountpoint(path->dentry)) return false; rcu_read_lock(); do { seq = read_seqbegin(&mount_lock); res = __path_is_mountpoint(path); } while (read_seqretry(&mount_lock, seq)); rcu_read_unlock(); return res; }

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ian kentian kent68100.00%1100.00%
Total68100.00%1100.00%

EXPORT_SYMBOL(path_is_mountpoint);
struct vfsmount *mnt_clone_internal(const struct path *path) { struct mount *p; p = clone_mnt(real_mount(path->mnt), path->dentry, CL_PRIVATE); if (IS_ERR(p)) return ERR_CAST(p); p->mnt.mnt_flags |= MNT_INTERNAL; return &p->mnt; }

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al viroal viro63100.00%4100.00%
Total63100.00%4100.00%


static inline void mangle(struct seq_file *m, const char *s) { seq_escape(m, s, " \t\n\\"); }

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miklos szeredimiklos szeredi26100.00%1100.00%
Total26100.00%1100.00%

/* * Simple .show_options callback for filesystems which don't want to * implement more complex mount option showing. * * See also save_mount_options(). */
int generic_show_options(struct seq_file *m, struct dentry *root) { const char *options; rcu_read_lock(); options = rcu_dereference(root->d_sb->s_options); if (options != NULL && options[0]) { seq_putc(m, ','); mangle(m, options); } rcu_read_unlock(); return 0; }

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miklos szeredimiklos szeredi5074.63%133.33%
al viroal viro1725.37%266.67%
Total67100.00%3100.00%

EXPORT_SYMBOL(generic_show_options); /* * If filesystem uses generic_show_options(), this function should be * called from the fill_super() callback. * * The .remount_fs callback usually needs to be handled in a special * way, to make sure, that previous options are not overwritten if the * remount fails. * * Also note, that if the filesystem's .remount_fs function doesn't * reset all options to their default value, but changes only newly * given options, then the displayed options will not reflect reality * any more. */
void save_mount_options(struct super_block *sb, char *options) { BUG_ON(sb->s_options); rcu_assign_pointer(sb->s_options, kstrdup(options, GFP_KERNEL)); }

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miklos szeredimiklos szeredi3085.71%150.00%
al viroal viro514.29%150.00%
Total35100.00%2100.00%

EXPORT_SYMBOL(save_mount_options);
void replace_mount_options(struct super_block *sb, char *options) { char *old = sb->s_options; rcu_assign_pointer(sb->s_options, options); if (old) { synchronize_rcu(); kfree(old); } }

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al viroal viro45100.00%1100.00%
Total45100.00%1100.00%

EXPORT_SYMBOL(replace_mount_options); #ifdef CONFIG_PROC_FS /* iterator; we want it to have access to namespace_sem, thus here... */
static void *m_start(struct seq_file *m, loff_t *pos) { struct proc_mounts *p = m->private; down_read(&namespace_sem); if (p->cached_event == p->ns->event) { void *v = p->cached_mount; if (*pos == p->cached_index) return v; if (*pos == p->cached_index + 1) { v = seq_list_next(v, &p->ns->list, &p->cached_index); return p->cached_mount = v; } } p->cached_event = p->ns->event; p->cached_mount = seq_list_start(&p->ns->list, *pos); p->cached_index = *pos; return p->cached_mount; }

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al viroal viro9969.23%222.22%
linus torvaldslinus torvalds3020.98%333.33%
pavel emelianovpavel emelianov64.20%111.11%
miklos szeredimiklos szeredi53.50%111.11%
yann droneaudyann droneaud21.40%111.11%
ram pairam pai10.70%111.11%
Total143100.00%9100.00%


static void *m_next(struct seq_file *m, void *v, loff_t *pos) { struct proc_mounts *p = m->private; p->cached_mount = seq_list_next(v, &p->ns->list, pos); p->cached_index = *pos; return p->cached_mount; }

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linus torvaldslinus torvalds3050.85%337.50%
al viroal viro1728.81%225.00%
pavel emelianovpavel emelianov58.47%112.50%
miklos szeredimiklos szeredi58.47%112.50%
yann droneaudyann droneaud23.39%112.50%
Total59100.00%8100.00%


static void m_stop(struct seq_file *m, void *v) { up_read(&namespace_sem); }

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linus torvaldslinus torvalds2095.24%375.00%
ram pairam pai14.76%125.00%
Total21100.00%4100.00%


static int m_show(struct seq_file *m, void *v) { struct proc_mounts *p = m->private; struct mount *r = list_entry(v, struct mount, mnt_list); return p->show(m, &r->mnt); }

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PersonTokensPropCommitsCommitProp
al viroal viro3363.46%225.00%
ram pairam pai1121.15%112.50%
linus torvaldslinus torvalds35.77%225.00%
yann droneaudyann droneaud23.85%112.50%
eric pariseric paris23.85%112.50%
kay sieverskay sievers11.92%112.50%
Total52100.00%8100.00%

const struct seq_operations mounts_op = { .start = m_start, .next = m_next, .stop = m_stop, .show = m_show, }; #endif /* CONFIG_PROC_FS */ /** * may_umount_tree - check if a mount tree is busy * @mnt: root of mount tree * * This is called to check if a tree of mounts has any * open files, pwds, chroots or sub mounts that are * busy. */
int may_umount_tree(struct vfsmount *m) { struct mount *mnt = real_mount(m); int actual_refs = 0; int minimum_refs = 0; struct mount *p; BUG_ON(!m); /* write lock needed for mnt_get_count */ lock_mount_hash(); for (p = mnt; p; p = next_mnt(p, mnt)) { actual_refs += mnt_get_count(p); minimum_refs += 2; } unlock_mount_hash(); if (actual_refs > minimum_refs) return 0; return 1; }

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PersonTokensPropCommitsCommitProp
andrew mortonandrew morton2932.22%222.22%
al viroal viro2224.44%333.33%
ram pairam pai2022.22%111.11%
linus torvaldslinus torvalds1516.67%111.11%
nick pigginnick piggin22.22%111.11%
ian kentian kent22.22%111.11%
Total90100.00%9100.00%

EXPORT_SYMBOL(may_umount_tree); /** * may_umount - check if a mount point is busy * @mnt: root of mount * * This is called to check if a mount point has any * open files, pwds, chroots or sub mounts. If the * mount has sub mounts this will return busy * regardless of whether the sub mounts are busy. * * Doesn't take quota and stuff into account. IOW, in some cases it will * give false negatives. The main reason why it's here is that we need * a non-destructive way to look for easily umountable filesystems. */
int may_umount(struct vfsmount *mnt) { int ret = 1; down_read(&namespace_sem); lock_mount_hash(); if (propagate_mount_busy(real_mount(mnt), 2)) ret = 0; unlock_mount_hash(); up_read(&namespace_sem); return ret; }

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PersonTokensPropCommitsCommitProp
al viroal viro1936.54%342.86%
andrew mortonandrew morton1834.62%228.57%
ram pairam pai1325.00%114.29%
ian kentian kent23.85%114.29%
Total52100.00%7100.00%

EXPORT_SYMBOL(may_umount); static HLIST_HEAD(unmounted); /* protected by namespace_sem */
static void namespace_unlock(void) { struct hlist_head head; hlist_move_list(&unmounted, &head); up_write(&namespace_sem); if (likely(hlist_empty(&head))) return; synchronize_rcu(); group_pin_kill(&head); }

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PersonTokensPropCommitsCommitProp
al viroal viro2552.08%571.43%
eric w. biedermaneric w. biederman1327.08%114.29%
ram pairam pai1020.83%114.29%
Total48100.00%7100.00%


static inline void namespace_lock(void) { down_write(&namespace_sem); }

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al viroal viro15100.00%2100.00%
Total15100.00%2100.00%

enum umount_tree_flags { UMOUNT_SYNC = 1, UMOUNT_PROPAGATE = 2, UMOUNT_CONNECTED = 4, };
static bool disconnect_mount(struct mount *mnt, enum umount_tree_flags how) { /* Leaving mounts connected is only valid for lazy umounts */ if (how & UMOUNT_SYNC) return true; /* A mount without a parent has nothing to be connected to */ if (!mnt_has_parent(mnt)) return true; /* Because the reference counting rules change when mounts are * unmounted and connected, umounted mounts may not be * connected to mounted mounts. */ if (!(mnt->mnt_parent->mnt.mnt_flags & MNT_UMOUNT)) return true; /* Has it been requested that the mount remain connected? */ if (how & UMOUNT_CONNECTED) return false; /* Is the mount locked such that it needs to remain connected? */ if (IS_MNT_LOCKED(mnt)) return false; /* By default disconnect the mount */ return true; }

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eric w. biedermaneric w. biederman81100.00%1100.00%
Total81100.00%1100.00%

/* * mount_lock must be held * namespace_sem must be held for write */
static void umount_tree(struct mount *mnt, enum umount_tree_flags how) { LIST_HEAD(tmp_list); struct mount *p; if (how & UMOUNT_PROPAGATE) propagate_mount_unlock(mnt); /* Gather the mounts to umount */ for (p = mnt; p; p = next_mnt(p, mnt)) { p->mnt.mnt_flags |= MNT_UMOUNT; list_move(&p->mnt_list, &tmp_list); } /* Hide the mounts from mnt_mounts */ list_for_each_entry(p, &tmp_list, mnt_list) { list_del_init(&p->mnt_child); } /* Add propogated mounts to the tmp_list */ if (how & UMOUNT_PROPAGATE) propagate_umount(&tmp_list); while (!list_empty(&tmp_list)) { struct mnt_namespace *ns; bool disconnect; p = list_first_entry(&tmp_list, struct mount, mnt_list); list_del_init(&p->mnt_expire); list_del_init(&p->mnt_list); ns = p->mnt_ns; if (ns) { ns->mounts--; __touch_mnt_namespace(ns); } p->mnt_ns = NULL; if (how & UMOUNT_SYNC) p->mnt.mnt_flags |= MNT_SYNC_UMOUNT; disconnect = disconnect_mount(p, how); pin_insert_group(&p->mnt_umount, &p->mnt_parent->mnt, disconnect ? &unmounted : NULL); if (mnt_has_parent(p)) { mnt_add_count(p->mnt_parent, -1); if (!disconnect) { /* Don't forget about p */ list_add_tail(&p->mnt_child, &p->mnt_parent->mnt_mounts); } else { umount_mnt(p); } } change_mnt_propagation(p, MS_PRIVATE); } }

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PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman11239.30%936.00%
al viroal viro9332.63%1144.00%
linus torvaldslinus torvalds5117.89%14.00%
ram pairam pai258.77%28.00%
david howellsdavid howells31.05%14.00%
kirill korotaevkirill korotaev10.35%14.00%
Total285100.00%25100.00%

static void shrink_submounts(struct mount *mnt);
static int do_umount(struct mount *mnt, int flags) { struct super_block *sb = mnt->mnt.mnt_sb; int retval; retval = security_sb_umount(&mnt->mnt, flags); if (retval) return retval; /* * Allow userspace to request a mountpoint be expired rather than * unmounting unconditionally. Unmount only happens if: * (1) the mark is already set (the mark is cleared by mntput()) * (2) the usage count == 1 [parent vfsmount] + 1 [sys_umount] */ if (flags & MNT_EXPIRE) { if (&mnt->mnt == current->fs->root.mnt || flags & (MNT_FORCE | MNT_DETACH)) return -EINVAL; /* * probably don't strictly need the lock here if we examined * all race cases, but it's a slowpath. */ lock_mount_hash(); if (mnt_get_count(mnt) != 2) { unlock_mount_hash(); return -EBUSY; } unlock_mount_hash(); if (!xchg(&mnt->mnt_expiry_mark, 1)) return -EAGAIN; } /* * If we may have to abort operations to get out of this * mount, and they will themselves hold resources we must * allow the fs to do things. In the Unix tradition of * 'Gee thats tricky lets do it in userspace' the umount_begin * might fail to complete on the first run through as other tasks * must return, and the like. Thats for the mount program to worry * about for the moment. */ if (flags & MNT_FORCE && sb->s_op->umount_begin) { sb->s_op->umount_begin(sb); } /* * No sense to grab the lock for this test, but test itself looks * somewhat bogus. Suggestions for better replacement? * Ho-hum... In principle, we might treat that as umount + switch * to rootfs. GC would eventually take care of the old vfsmount. * Actually it makes sense, especially if rootfs would contain a * /reboot - static binary that would close all descriptors and * call reboot(9). Then init(8) could umount root and exec /reboot. */ if (&mnt->mnt == current->fs->root.mnt && !(flags & MNT_DETACH)) { /* * Special case for "unmounting" root ... * we just try to remount it readonly. */ if (!capable(CAP_SYS_ADMIN)) return -EPERM; down_write(&sb->s_umount); if (!(sb->s_flags & MS_RDONLY)) retval = do_remount_sb(sb, MS_RDONLY, NULL, 0); up_write(&sb->s_umount); return retval; } namespace_lock(); lock_mount_hash(); event++; if (flags & MNT_DETACH) { if (!list_empty(&mnt->mnt_list)) umount_tree(mnt, UMOUNT_PROPAGATE); retval = 0; } else { shrink_submounts(mnt); retval = -EBUSY; if (!propagate_mount_busy(mnt, 2)) { if (!list_empty(&mnt->mnt_list)) umount_tree(mnt, UMOUNT_PROPAGATE|UMOUNT_SYNC); retval = 0; } } unlock_mount_hash(); namespace_unlock(); return retval; }

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linus torvaldslinus torvalds13942.51%417.39%
al viroal viro7322.32%834.78%
david howellsdavid howells5918.04%14.35%
andy lutomirskiandy lutomirski123.67%14.35%
stephen d. smalleystephen d. smalley113.36%14.35%
ram pairam pai92.75%28.70%
nick pigginnick piggin72.14%14.35%
jan blunckjan blunck61.83%14.35%
greg kroah-hartmangreg kroah-hartman51.53%28.70%
eric w. biedermaneric w. biederman41.22%14.35%
andrew mortonandrew morton20.61%14.35%
Total327100.00%23100.00%

/* * __detach_mounts - lazily unmount all mounts on the specified dentry * * During unlink, rmdir, and d_drop it is possible to loose the path * to an existing mountpoint, and wind up leaking the mount. * detach_mounts allows lazily unmounting those mounts instead of * leaking them. * * The caller may hold dentry->d_inode->i_mutex. */
void __detach_mounts(struct dentry *dentry) { struct mountpoint *mp; struct mount *mnt; namespace_lock(); lock_mount_hash(); mp = lookup_mountpoint(dentry); if (IS_ERR_OR_NULL(mp)) goto out_unlock; event++; while (!hlist_empty(&mp->m_list)) { mnt = hlist_entry(mp->m_list.first, struct mount, mnt_mp_list); if (mnt->mnt.mnt_flags & MNT_UMOUNT) { hlist_add_head(&mnt->mnt_umount.s_list, &unmounted); umount_mnt(mnt); } else umount_tree(mnt, UMOUNT_CONNECTED); } put_mountpoint(mp); out_unlock: unlock_mount_hash(); namespace_unlock(); }

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eric w. biedermaneric w. biederman12397.62%685.71%
andrey ulanovandrey ulanov32.38%114.29%
Total126100.00%7100.00%

/* * Is the caller allowed to modify his namespace? */
static inline bool may_mount(void) { return ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN); }

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al viroal viro23100.00%1100.00%
Total23100.00%1100.00%


static inline bool may_mandlock(void) { #ifndef CONFIG_MANDATORY_FILE_LOCKING return false; #endif return capable(CAP_SYS_ADMIN); }

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jeff laytonjeff layton1982.61%150.00%
eric w. biedermaneric w. biederman417.39%150.00%
Total23100.00%2100.00%

/* * Now umount can handle mount points as well as block devices. * This is important for filesystems which use unnamed block devices. * * We now support a flag for forced unmount like the other 'big iron' * unixes. Our API is identical to OSF/1 to avoid making a mess of AMD */ SYSCALL_DEFINE2(umount, char __user *, name, int, flags) { struct path path; struct mount *mnt; int retval; int lookup_flags = 0; if (flags & ~(MNT_FORCE | MNT_DETACH | MNT_EXPIRE | UMOUNT_NOFOLLOW)) return -EINVAL; if (!may_mount()) return -EPERM; if (!(flags & UMOUNT_NOFOLLOW)) lookup_flags |= LOOKUP_FOLLOW; retval = user_path_mountpoint_at(AT_FDCWD, name, lookup_flags, &path); if (retval) goto out; mnt = real_mount(path.mnt); retval = -EINVAL; if (path.dentry != path.mnt->mnt_root) goto dput_and_out; if (!check_mnt(mnt)) goto dput_and_out; if (mnt->mnt.mnt_flags & MNT_LOCKED) goto dput_and_out; retval = -EPERM; if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN)) goto dput_and_out; retval = do_umount(mnt, flags); dput_and_out: /* we mustn't call path_put() as that would clear mnt_expiry_mark */ dput(path.dentry); mntput_no_expire(mnt); out: return retval; } #ifdef __ARCH_WANT_SYS_OLDUMOUNT /* * The 2.0 compatible umount. No flags. */ SYSCALL_DEFINE1(oldumount, char __user *, name) { return sys_umount(name, 0); } #endif
static bool is_mnt_ns_file(struct dentry *dentry) { /* Is this a proxy for a mount namespace? */ return dentry->d_op == &ns_dentry_operations && dentry->d_fsdata == &mntns_operations; }

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PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman1866.67%250.00%
al viroal viro933.33%250.00%
Total27100.00%4100.00%


struct mnt_namespace *to_mnt_ns(struct ns_common *ns) { return container_of(ns, struct mnt_namespace, ns); }

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al viroal viro23100.00%1100.00%
Total23100.00%1100.00%


static bool mnt_ns_loop(struct dentry *dentry) { /* Could bind mounting the mount namespace inode cause a * mount namespace loop? */ struct mnt_namespace *mnt_ns; if (!is_mnt_ns_file(dentry)) return false; mnt_ns = to_mnt_ns(get_proc_ns(dentry->d_inode)); return current->nsproxy->mnt_ns->seq >= mnt_ns->seq; }

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eric w. biedermaneric w. biederman5094.34%266.67%
al viroal viro35.66%133.33%
Total53100.00%3100.00%


struct mount *copy_tree(struct mount *mnt, struct dentry *dentry, int flag) { struct mount *res, *p, *q, *r, *parent; if (!(flag & CL_COPY_UNBINDABLE) && IS_MNT_UNBINDABLE(mnt)) return ERR_PTR(-EINVAL); if (!(flag & CL_COPY_MNT_NS_FILE) && is_mnt_ns_file(dentry)) return ERR_PTR(-EINVAL); res = q = clone_mnt(mnt, dentry, flag); if (IS_ERR(q)) return q; q->mnt_mountpoint = mnt->mnt_mountpoint; p = mnt; list_for_each_entry(r, &mnt->mnt_mounts, mnt_child) { struct mount *s; if (!is_subdir(r->mnt_mountpoint, dentry)) continue; for (s = r; s; s = next_mnt(s, r)) { struct mount *t = NULL; if (!(flag & CL_COPY_UNBINDABLE) && IS_MNT_UNBINDABLE(s)) { s = skip_mnt_tree(s); continue; } if (!(flag & CL_COPY_MNT_NS_FILE) && is_mnt_ns_file(s->mnt.mnt_root)) { s = skip_mnt_tree(s); continue; } while (p != s->mnt_parent) { p = p->mnt_parent; q = q->mnt_parent; } p = s; parent = q; q = clone_mnt(p, p->mnt.mnt_root, flag); if (IS_ERR(q)) goto out; lock_mount_hash(); list_add_tail(&q->mnt_list, &res->mnt_list); mnt_set_mountpoint(parent, p->mnt_mp, q); if (!list_empty(&parent->mnt_mounts)) { t = list_last_entry(&parent->mnt_mounts, struct mount, mnt_child); if (t->mnt_mp != p->mnt_mp) t = NULL; } attach_shadowed(q, parent, t); unlock_mount_hash(); } } return res; out: if (res) { lock_mount_hash(); umount_tree(res, UMOUNT_SYNC); unlock_mount_hash(); } return q; }

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linus torvaldslinus torvalds13134.20%15.56%
al viroal viro9424.54%844.44%
eric w. biedermaneric w. biederman5213.58%211.11%
ram pairam pai4612.01%316.67%
andries brouwerandries brouwer3910.18%15.56%
david howellsdavid howells174.44%15.56%
domen puncerdomen puncer30.78%15.56%
jan blunckjan blunck10.26%15.56%
Total383100.00%18100.00%

/* Caller should check returned pointer for errors */
struct vfsmount *collect_mounts(const struct path *path) { struct mount *tree; namespace_lock(); if (!check_mnt(real_mount(path->mnt))) tree = ERR_PTR(-EINVAL); else tree = copy_tree(real_mount(path->mnt), path->dentry, CL_COPY_ALL | CL_PRIVATE); namespace_unlock(); if (IS_ERR(tree)) return ERR_CAST(tree); return &tree->mnt; }

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al viroal viro5058.82%770.00%
eric w. biedermaneric w. biederman2225.88%110.00%
david howellsdavid howells910.59%110.00%
dan carpenterdan carpenter44.71%110.00%
Total85100.00%10100.00%


void drop_collected_mounts(struct vfsmount *mnt) { namespace_lock(); lock_mount_hash(); umount_tree(real_mount(mnt), UMOUNT_SYNC); unlock_mount_hash(); namespace_unlock(); }

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al viroal viro3196.88%583.33%
eric w. biedermaneric w. biederman13.12%116.67%
Total32100.00%6100.00%

/** * clone_private_mount - create a private clone of a path * * This creates a new vfsmount, which will be the clone of @path. The new will * not be attached anywhere in the namespace and will be private (i.e. changes * to the originating mount won't be propagated into this). * * Release with mntput(). */
struct vfsmount *clone_private_mount(const struct path *path) { struct mount *old_mnt = real_mount(path->mnt); struct mount *new_mnt; if (IS_MNT_UNBINDABLE(old_mnt)) return ERR_PTR(-EINVAL); new_mnt = clone_mnt(old_mnt, path->dentry, CL_PRIVATE); if (IS_ERR(new_mnt)) return ERR_CAST(new_mnt); return &new_mnt->mnt; }

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miklos szeredimiklos szeredi7598.68%150.00%
al viroal viro11.32%150.00%
Total76100.00%2100.00%

EXPORT_SYMBOL_GPL(clone_private_mount);
int iterate_mounts(int (*f)(struct vfsmount *, void *), void *arg, struct vfsmount *root) { struct mount *mnt; int res = f(root, arg); if (res) return res; list_for_each_entry(mnt, &real_mount(root)->mnt_list, mnt_list) { res = f(&mnt->mnt, arg); if (res) return res; } return 0; }

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al viroal viro82100.00%2100.00%
Total82100.00%2100.00%


static void cleanup_group_ids(struct mount *mnt, struct mount *end) { struct mount *p; for (p = mnt; p != end; p = next_mnt(p, mnt)) { if (p->mnt_group_id && !IS_MNT_SHARED(p)) mnt_release_group_id(p); } }

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miklos szeredimiklos szeredi5694.92%133.33%
al viroal viro35.08%266.67%
Total59100.00%3100.00%


static int invent_group_ids(struct mount *mnt, bool recurse) { struct mount *p; for (p = mnt; p; p = recurse ? next_mnt(p, mnt) : NULL) { if (!p->mnt_group_id && !IS_MNT_SHARED(p)) { int err = mnt_alloc_group_id(p); if (err) { cleanup_group_ids(mnt, p); return err; } } } return 0; }

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miklos szeredimiklos szeredi8297.62%133.33%
al viroal viro22.38%266.67%
Total84100.00%3100.00%


int count_mounts(struct mnt_namespace *ns, struct mount *mnt) { unsigned int max = READ_ONCE(sysctl_mount_max); unsigned int mounts = 0, old, pending, sum; struct mount *p; for (p = mnt; p; p = next_mnt(p, mnt)) mounts++; old = ns->mounts; pending = ns->pending_mounts; sum = old + pending; if ((old > sum) || (pending > sum) || (max < sum) || (mounts > (max - sum))) return -ENOSPC; ns->pending_mounts = pending + mounts; return 0; }

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eric w. biedermaneric w. biederman124100.00%1100.00%
Total124100.00%1100.00%

/* * @source_mnt : mount tree to be attached * @nd : place the mount tree @source_mnt is attached * @parent_nd : if non-null, detach the source_mnt from its parent and * store the parent mount and mountpoint dentry. * (done when source_mnt is moved) * * NOTE: in the table below explains the semantics when a source mount * of a given type is attached to a destination mount of a given type. * --------------------------------------------------------------------------- * | BIND MOUNT OPERATION | * |************************************************************************** * | source-->| shared | private | slave | unbindable | * | dest | | | | | * | | | | | | | * | v | | | | | * |************************************************************************** * | shared | shared (++) | shared (+) | shared(+++)| invalid | * | | | | | | * |non-shared| shared (+) | private | slave (*) | invalid | * *************************************************************************** * A bind operation clones the source mount and mounts the clone on the * destination mount. * * (++) the cloned mount is propagated to all the mounts in the propagation * tree of the destination mount and the cloned mount is added to * the peer group of the source mount. * (+) the cloned mount is created under the destination mount and is marked * as shared. The cloned mount is added to the peer group of the source * mount. * (+++) the mount is propagated to all the mounts in the propagation tree * of the destination mount and the cloned mount is made slave * of the same master as that of the source mount. The cloned mount * is marked as 'shared and slave'. * (*) the cloned mount is made a slave of the same master as that of the * source mount. * * --------------------------------------------------------------------------- * | MOVE MOUNT OPERATION | * |************************************************************************** * | source-->| shared | private | slave | unbindable | * | dest | | | | | * | | | | | | | * | v | | | | | * |************************************************************************** * | shared | shared (+) | shared (+) | shared(+++) | invalid | * | | | | | | * |non-shared| shared (+*) | private | slave (*) | unbindable | * *************************************************************************** * * (+) the mount is moved to the destination. And is then propagated to * all the mounts in the propagation tree of the destination mount. * (+*) the mount is moved to the destination. * (+++) the mount is moved to the destination and is then propagated to * all the mounts belonging to the destination mount's propagation tree. * the mount is marked as 'shared and slave'. * (*) the mount continues to be a slave at the new location. * * if the source mount is a tree, the operations explained above is * applied to each mount in the tree. * Must be called without spinlocks held, since this function can sleep * in allocations. */
static int attach_recursive_mnt(struct mount *source_mnt, struct mount *dest_mnt, struct mountpoint *dest_mp, struct path *parent_path) { HLIST_HEAD(tree_list); struct mnt_namespace *ns = dest_mnt->mnt_ns; struct mount *child, *p; struct hlist_node *n; int err; /* Is there space to add these mounts to the mount namespace? */ if (!parent_path) { err = count_mounts(ns, source_mnt); if (err) goto out; } if (IS_MNT_SHARED(dest_mnt)) { err = invent_group_ids(source_mnt, true); if (err) goto out; err = propagate_mnt(dest_mnt, dest_mp, source_mnt, &tree_list); lock_mount_hash(); if (err) goto out_cleanup_ids; for (p = source_mnt; p; p = next_mnt(p, source_mnt)) set_mnt_shared(p); } else { lock_mount_hash(); } if (parent_path) { detach_mnt(source_mnt, parent_path); attach_mnt(source_mnt, dest_mnt, dest_mp); touch_mnt_namespace(source_mnt->mnt_ns); } else { mnt_set_mountpoint(dest_mnt, dest_mp, source_mnt); commit_tree(source_mnt, NULL); } hlist_for_each_entry_safe(child, n, &tree_list, mnt_hash) { struct mount *q; hlist_del_init(&child->mnt_hash); q = __lookup_mnt_last(&child->mnt_parent->mnt, child->mnt_mountpoint); commit_tree(child, q); } unlock_mount_hash(); return 0; out_cleanup_ids: while (!hlist_empty(&tree_list)) { child = hlist_entry(tree_list.first, struct mount, mnt_hash); child->mnt_parent->mnt_ns->pending_mounts = 0; umount_tree(child, UMOUNT_SYNC); } unlock_mount_hash(); cleanup_group_ids(source_mnt, NULL); out: ns->pending_mounts = 0; return err; }

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ram pairam pai12438.27%211.11%
al viroal viro9930.56%1161.11%
eric w. biedermaneric w. biederman5015.43%211.11%
miklos szeredimiklos szeredi4814.81%15.56%
kirill korotaevkirill korotaev20.62%15.56%
serge hallynserge hallyn10.31%15.56%
Total324100.00%18100.00%


static struct mountpoint *lock_mount(struct path *path) { struct vfsmount *mnt; struct dentry *dentry = path->dentry; retry: inode_lock(dentry->d_inode); if (unlikely(cant_mount(dentry))) { inode_unlock(dentry->d_inode); return ERR_PTR(-ENOENT); } namespace_lock(); mnt = lookup_mnt(path); if (likely(!mnt)) { struct mountpoint *mp = get_mountpoint(dentry); if (IS_ERR(mp)) { namespace_unlock(); inode_unlock(dentry->d_inode); return mp; } return mp; } namespace_unlock(); inode_unlock(path->dentry->d_inode); path_put(path); path->mnt = mnt; dentry = path->dentry = dget(mnt->mnt_root); goto retry; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro15599.36%480.00%
eric w. biedermaneric w. biederman10.64%120.00%
Total156100.00%5100.00%


static void unlock_mount(struct mountpoint *where) { struct dentry *dentry = where->m_dentry; read_seqlock_excl(&mount_lock); put_mountpoint(where); read_sequnlock_excl(&mount_lock); namespace_unlock(); inode_unlock(dentry->d_inode); }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro3574.47%480.00%
eric w. biedermaneric w. biederman1225.53%120.00%
Total47100.00%5100.00%


static int graft_tree(struct mount *mnt, struct mount *p, struct mountpoint *mp) { if (mnt->mnt.mnt_sb->s_flags & MS_NOUSER) return -EINVAL; if (d_is_dir(mp->m_dentry) != d_is_dir(mnt->mnt.mnt_root)) return -ENOTDIR; return attach_recursive_mnt(mnt, p, mp, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds5070.42%222.22%
al viroal viro1622.54%444.44%
ram pairam pai34.23%222.22%
david howellsdavid howells22.82%111.11%
Total71100.00%9100.00%

/* * Sanity check the flags to change_mnt_propagation. */
static int flags_to_propagation_type(int flags) { int type = flags & ~(MS_REC | MS_SILENT); /* Fail if any non-propagation flags are set */ if (type & ~(MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE)) return 0; /* Only one propagation flag should be set */ if (!is_power_of_2(type)) return 0; return type; }

Contributors

PersonTokensPropCommitsCommitProp
valerie auroravalerie aurora5192.73%150.00%
roman borisovroman borisov47.27%150.00%
Total55100.00%2100.00%

/* * recursively change the type of the mountpoint. */
static int do_change_type(struct path *path, int flag) { struct mount *m; struct mount *mnt = real_mount(path->mnt); int recurse = flag & MS_REC; int type; int err = 0; if (path->dentry != path->mnt->mnt_root) return -EINVAL; type = flags_to_propagation_type(flag); if (!type) return -EINVAL; namespace_lock(); if (type == MS_SHARED) { err = invent_group_ids(mnt, recurse); if (err) goto out_unlock; } lock_mount_hash(); for (m = mnt; m; m = (recurse ? next_mnt(m, mnt) : NULL)) change_mnt_propagation(m, type); unlock_mount_hash(); out_unlock: namespace_unlock(); return err; }

Contributors

PersonTokensPropCommitsCommitProp
ram pairam pai7852.35%111.11%
miklos szeredimiklos szeredi3221.48%111.11%
al viroal viro2013.42%555.56%
valerie auroravalerie aurora1610.74%111.11%
jan blunckjan blunck32.01%111.11%
Total149100.00%9100.00%


static bool has_locked_children(struct mount *mnt, struct dentry *dentry) { struct mount *child; list_for_each_entry(child, &mnt->mnt_mounts, mnt_child) { if (!is_subdir(child->mnt_mountpoint, dentry)) continue; if (child->mnt.mnt_flags & MNT_LOCKED) return true; } return false; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman60100.00%1100.00%
Total60100.00%1100.00%

/* * do loopback mount. */
static int do_loopback(struct path *path, const char *old_name, int recurse) { struct path old_path; struct mount *mnt = NULL, *old, *parent; struct mountpoint *mp; int err; if (!old_name || !*old_name) return -EINVAL; err = kern_path(old_name, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &old_path); if (err) return err; err = -EINVAL; if (mnt_ns_loop(old_path.dentry)) goto out; mp = lock_mount(path); err = PTR_ERR(mp); if (IS_ERR(mp)) goto out; old = real_mount(old_path.mnt); parent = real_mount(path->mnt); err = -EINVAL; if (IS_MNT_UNBINDABLE(old)) goto out2; if (!check_mnt(parent)) goto out2; if (!check_mnt(old) && old_path.dentry->d_op != &ns_dentry_operations) goto out2; if (!recurse && has_locked_children(old, old_path.dentry)) goto out2; if (recurse) mnt = copy_tree(old, old_path.dentry, CL_COPY_MNT_NS_FILE); else mnt = clone_mnt(old, old_path.dentry, 0); if (IS_ERR(mnt)) { err = PTR_ERR(mnt); goto out2; } mnt->mnt.mnt_flags &= ~MNT_LOCKED; err = graft_tree(mnt, parent, mp); if (err) { lock_mount_hash(); umount_tree(mnt, UMOUNT_SYNC); unlock_mount_hash(); } out2: unlock_mount(mp); out: path_put(&old_path); return err; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds12239.74%310.71%
al viroal viro10835.18%1242.86%
eric w. biedermaneric w. biederman4414.33%414.29%
ram pairam pai144.56%310.71%
david howellsdavid howells123.91%13.57%
jan blunckjan blunck30.98%27.14%
trond myklebusttrond myklebust20.65%13.57%
andrey vaginandrey vagin10.33%13.57%
andrew mortonandrew morton10.33%13.57%
Total307100.00%28100.00%


static int change_mount_flags(struct vfsmount *mnt, int ms_flags) { int error = 0; int readonly_request = 0; if (ms_flags & MS_RDONLY) readonly_request = 1; if (readonly_request == __mnt_is_readonly(mnt)) return 0; if (readonly_request) error = mnt_make_readonly(real_mount(mnt)); else __mnt_unmake_readonly(real_mount(mnt)); return error; }

Contributors

PersonTokensPropCommitsCommitProp
dave hansendave hansen6691.67%150.00%
al viroal viro68.33%150.00%
Total72100.00%2100.00%

/* * change filesystem flags. dir should be a physical root of filesystem. * If you've mounted a non-root directory somewhere and want to do remount * on it - tough luck. */
static int do_remount(struct path *path, int flags, int mnt_flags, void *data) { int err; struct super_block *sb = path->mnt->mnt_sb; struct mount *mnt = real_mount(path->mnt); if (!check_mnt(mnt)) return -EINVAL; if (path->dentry != path->mnt->mnt_root) return -EINVAL; /* Don't allow changing of locked mnt flags. * * No locks need to be held here while testing the various * MNT_LOCK flags because those flags can never be cleared * once they are set. */ if ((mnt->mnt.mnt_flags & MNT_LOCK_READONLY) && !(mnt_flags & MNT_READONLY)) { return -EPERM; } if ((mnt->mnt.mnt_flags & MNT_LOCK_NODEV) && !(mnt_flags & MNT_NODEV)) { return -EPERM; } if ((mnt->mnt.mnt_flags & MNT_LOCK_NOSUID) && !(mnt_flags & MNT_NOSUID)) { return -EPERM; } if ((mnt->mnt.mnt_flags & MNT_LOCK_NOEXEC) && !(mnt_flags & MNT_NOEXEC)) { return -EPERM; } if ((mnt->mnt.mnt_flags & MNT_LOCK_ATIME) && ((mnt->mnt.mnt_flags & MNT_ATIME_MASK) != (mnt_flags & MNT_ATIME_MASK))) { return -EPERM; } err = security_sb_remount(sb, data); if (err) return err; down_write(&sb->s_umount); if (flags & MS_BIND) err = change_mount_flags(path->mnt, flags); else if (!capable(CAP_SYS_ADMIN)) err = -EPERM; else err = do_remount_sb(sb, flags, data, 0); if (!err) { lock_mount_hash(); mnt_flags |= mnt->mnt.mnt_flags & ~MNT_USER_SETTABLE_MASK; mnt->mnt.mnt_flags = mnt_flags; touch_mnt_namespace(mnt->mnt_ns); unlock_mount_hash(); } up_write(&sb->s_umount); return err; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman13941.99%320.00%
linus torvaldslinus torvalds9629.00%213.33%
al viroal viro5817.52%640.00%
dave hansendave hansen175.14%16.67%
eric pariseric paris164.83%16.67%
jan blunckjan blunck30.91%16.67%
andrew mortonandrew morton20.60%16.67%
Total331100.00%15100.00%


static inline int tree_contains_unbindable(struct mount *mnt) { struct mount *p; for (p = mnt; p; p = next_mnt(p, mnt)) { if (IS_MNT_UNBINDABLE(p)) return 1; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
ram pairam pai4795.92%133.33%
al viroal viro24.08%266.67%
Total49100.00%3100.00%


static int do_move_mount(struct path *path, const char *old_name) { struct path old_path, parent_path; struct mount *p; struct mount *old; struct mountpoint *mp; int err; if (!old_name || !*old_name) return -EINVAL; err = kern_path(old_name, LOOKUP_FOLLOW, &old_path); if (err) return err; mp = lock_mount(path); err = PTR_ERR(mp); if (IS_ERR(mp)) goto out; old = real_mount(old_path.mnt); p = real_mount(path->mnt); err = -EINVAL; if (!check_mnt(p) || !check_mnt(old)) goto out1; if (old->mnt.mnt_flags & MNT_LOCKED) goto out1; err = -EINVAL; if (old_path.dentry != old_path.mnt->mnt_root) goto out1; if (!mnt_has_parent(old)) goto out1; if (d_is_dir(path->dentry) != d_is_dir(old_path.dentry)) goto out1; /* * Don't move a mount residing in a shared parent. */ if (IS_MNT_SHARED(old->mnt_parent)) goto out1; /* * Don't move a mount tree containing unbindable mounts to a destination * mount which is shared. */ if (IS_MNT_SHARED(p) && tree_contains_unbindable(old)) goto out1; err = -ELOOP; for (; mnt_has_parent(p); p = p->mnt_parent) if (p == old) goto out1; err = attach_recursive_mnt(old, real_mount(path->mnt), mp, &parent_path); if (err) goto out1; /* if the mount is moved, it should no longer be expire * automatically */ list_del_init(&old->mnt_expire); out1: unlock_mount(mp); out: if (!err) path_put(&parent_path); path_put(&old_path); return err; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds15648.75%14.17%
al viroal viro8727.19%1458.33%
ram pairam pai3611.25%28.33%
david howellsdavid howells165.00%312.50%
eric w. biedermaneric w. biederman134.06%14.17%
jan blunckjan blunck113.44%28.33%
miklos szeredimiklos szeredi10.31%14.17%
Total320100.00%24100.00%


static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype) { int err; const char *subtype = strchr(fstype, '.'); if (subtype) { subtype++; err = -EINVAL; if (!subtype[0]) goto err; } else subtype = ""; mnt->mnt_sb->s_subtype = kstrdup(subtype, GFP_KERNEL); err = -ENOMEM; if (!mnt->mnt_sb->s_subtype) goto err; return mnt; err: mntput(mnt); return ERR_PTR(err); }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro7770.64%350.00%
linus torvaldslinus torvalds2724.77%233.33%
david howellsdavid howells54.59%116.67%
Total109100.00%6100.00%

/* * add a mount into a namespace's mount tree */
static int do_add_mount(struct mount *newmnt, struct path *path, int mnt_flags) { struct mountpoint *mp; struct mount *parent; int err; mnt_flags &= ~MNT_INTERNAL_FLAGS; mp = lock_mount(path); if (IS_ERR(mp)) return PTR_ERR(mp); parent = real_mount(path->mnt); err = -EINVAL; if (unlikely(!check_mnt(parent))) { /* that's acceptable only for automounts done in private ns */ if (!(mnt_flags & MNT_SHRINKABLE)) goto unlock; /* ... and for those we'd better have mountpoint still alive */ if (!parent->mnt_ns) goto unlock; } /* Refuse the same filesystem on the same mount point */ err = -EBUSY; if (path->mnt->mnt_sb == newmnt->mnt.mnt_sb && path->mnt->mnt_root == path->dentry) goto unlock; err = -EINVAL; if (d_is_symlink(newmnt->mnt.mnt_root)) goto unlock; newmnt->mnt.mnt_flags = mnt_flags; err = graft_tree(newmnt, parent, mp); unlock: unlock_mount(mp); return err; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro9952.38%1062.50%
linus torvaldslinus torvalds5529.10%16.25%
david howellsdavid howells3015.87%318.75%
jan blunckjan blunck42.12%16.25%
ram pairam pai10.53%16.25%
Total189100.00%16100.00%

static bool mount_too_revealing(struct vfsmount *mnt, int *new_mnt_flags); /* * create a new mount for userspace and request it to be added into the * namespace's tree */
static int do_new_mount(struct path *path, const char *fstype, int flags, int mnt_flags, const char *name, void *data) { struct file_system_type *type; struct vfsmount *mnt; int err; if (!fstype) return -EINVAL; type = get_fs_type(fstype); if (!type) return -ENODEV; mnt = vfs_kern_mount(type, flags, name, data); if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) && !mnt->mnt_sb->s_subtype) mnt = fs_set_subtype(mnt, fstype); put_filesystem(type); if (IS_ERR(mnt)) return PTR_ERR(mnt); if (mount_too_revealing(mnt, &mnt_flags)) { mntput(mnt); return -EPERM; } err = do_add_mount(real_mount(mnt), path, mnt_flags); if (err) mntput(mnt); return err; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro9754.19%360.00%
eric w. biedermaneric w. biederman8245.81%240.00%
Total179100.00%5100.00%


int finish_automount(struct vfsmount *m, struct path *path) { struct mount *mnt = real_mount(m); int err; /* The new mount record should have at least 2 refs to prevent it being * expired before we get a chance to add it */ BUG_ON(mnt_get_count(mnt) < 2); if (m->mnt_sb == path->mnt->mnt_sb && m->mnt_root == path->dentry) { err = -ELOOP; goto fail; } err = do_add_mount(mnt, path, path->mnt->mnt_flags | MNT_SHRINKABLE); if (!err) return 0; fail: /* remove m from any expiration list it may be on */ if (!list_empty(&mnt->mnt_expire)) { namespace_lock(); list_del_init(&mnt->mnt_expire); namespace_unlock(); } mntput(m); mntput(m); return err; }

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PersonTokensPropCommitsCommitProp
al viroal viro137100.00%5100.00%
Total137100.00%5100.00%

/** * mnt_set_expiry - Put a mount on an expiration list * @mnt: The mount to list. * @expiry_list: The list to add the mount to. */
void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list) { namespace_lock(); list_add_tail(&real_mount(mnt)->mnt_expire, expiry_list); namespace_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
david howellsdavid howells2779.41%133.33%
al viroal viro720.59%266.67%
Total34100.00%3100.00%

EXPORT_SYMBOL(mnt_set_expiry); /* * process a list of expirable mountpoints with the intent of discarding any * mountpoints that aren't in use and haven't been touched since last we came * here */
void mark_mounts_for_expiry(struct list_head *mounts) { struct mount *mnt, *next; LIST_HEAD(graveyard); if (list_empty(mounts)) return; namespace_lock(); lock_mount_hash(); /* extract from the expiration list every vfsmount that matches the * following criteria: * - only referenced by its parent vfsmount * - still marked for expiry (marked on the last call here; marks are * cleared by mntput()) */ list_for_each_entry_safe(mnt, next, mounts, mnt_expire) { if (!xchg(&mnt->mnt_expiry_mark, 1) || propagate_mount_busy(mnt, 1)) continue; list_move(&mnt->mnt_expire, &graveyard); } while (!list_empty(&graveyard)) { mnt = list_first_entry(&graveyard, struct mount, mnt_expire); touch_mnt_namespace(mnt->mnt_ns); umount_tree(mnt, UMOUNT_PROPAGATE|UMOUNT_SYNC); } unlock_mount_hash(); namespace_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
david howellsdavid howells5039.06%18.33%
al viroal viro4635.94%650.00%
trond myklebusttrond myklebust1511.72%18.33%
christoph hellwigchristoph hellwig129.38%18.33%
eric w. biedermaneric w. biederman32.34%18.33%
ram pairam pai10.78%18.33%
miklos szeredimiklos szeredi10.78%18.33%
Total128100.00%12100.00%

EXPORT_SYMBOL_GPL(mark_mounts_for_expiry); /* * Ripoff of 'select_parent()' * * search the list of submounts for a given mountpoint, and move any * shrinkable submounts to the 'graveyard' list. */
static int select_submounts(struct mount *parent, struct list_head *graveyard) { struct mount *this_parent = parent; struct list_head *next; int found = 0; repeat: next = this_parent->mnt_mounts.next; resume: while (next != &this_parent->mnt_mounts) { struct list_head *tmp = next; struct mount *mnt = list_entry(tmp, struct mount, mnt_child); next = tmp->next; if (!(mnt->mnt.mnt_flags & MNT_SHRINKABLE)) continue; /* * Descend a level if the d_mounts list is non-empty. */ if (!list_empty(&mnt->mnt_mounts)) { this_parent = mnt; goto repeat; } if (!propagate_mount_busy(mnt, 1)) { list_move_tail(&mnt->mnt_expire, graveyard); found++; } } /* * All done at this level ... ascend and resume the search */ if (this_parent != parent) { next = this_parent->mnt_child.next; this_parent = this_parent->mnt_parent; goto resume; } return found; }

Contributors

PersonTokensPropCommitsCommitProp
trond myklebusttrond myklebust13980.35%125.00%
david howellsdavid howells2715.61%125.00%
al viroal viro63.47%125.00%
miklos szeredimiklos szeredi10.58%125.00%
Total173100.00%4100.00%

/* * process a list of expirable mountpoints with the intent of discarding any * submounts of a specific parent mountpoint * * mount_lock must be held for write */
static void shrink_submounts(struct mount *mnt) { LIST_HEAD(graveyard); struct mount *m; /* extract submounts of 'mountpoint' from the expiration list */ while (select_submounts(mnt, &graveyard)) { while (!list_empty(&graveyard)) { m = list_first_entry(&graveyard, struct mount, mnt_expire); touch_mnt_namespace(m->mnt_ns); umount_tree(m, UMOUNT_PROPAGATE|UMOUNT_SYNC); } } }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro3952.70%444.44%
trond myklebusttrond myklebust2027.03%111.11%
david howellsdavid howells79.46%111.11%
eric w. biedermaneric w. biederman56.76%222.22%
ram pairam pai34.05%111.11%
Total74100.00%9100.00%

/* * Some copy_from_user() implementations do not return the exact number of * bytes remaining to copy on a fault. But copy_mount_options() requires that. * Note that this function differs from copy_from_user() in that it will oops * on bad values of `to', rather than returning a short copy. */
static long exact_copy_from_user(void *to, const void __user * from, unsigned long n) { char *t = to; const char __user *f = from; char c; if (!access_ok(VERIFY_READ, from, n)) return n; while (n) { if (__get_user(c, f)) { memset(t, 0, n); break; } *t++ = c; f++; n--; } return n; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton94100.00%1100.00%
Total94100.00%1100.00%


void *copy_mount_options(const void __user * data) { int i; unsigned long size; char *copy; if (!data) return NULL; copy = kmalloc(PAGE_SIZE, GFP_KERNEL); if (!copy) return ERR_PTR(-ENOMEM); /* We only care that *some* data at the address the user * gave us is valid. Just in case, we'll zero * the remainder of the page. */ /* copy_from_user cannot cross TASK_SIZE ! */ size = TASK_SIZE - (unsigned long)data; if (size > PAGE_SIZE) size = PAGE_SIZE; i = size - exact_copy_from_user(copy, data, size); if (!i) { kfree(copy); return ERR_PTR(-EFAULT); } if (i != PAGE_SIZE) memset(copy + i, 0, PAGE_SIZE - i); return copy; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds10078.12%250.00%
al viroal viro2721.09%125.00%
andrew mortonandrew morton10.78%125.00%
Total128100.00%4100.00%


char *copy_mount_string(const void __user *data) { return data ? strndup_user(data, PAGE_SIZE) : NULL; }

Contributors

PersonTokensPropCommitsCommitProp
vegard nossumvegard nossum1875.00%150.00%
tim gardnertim gardner625.00%150.00%
Total24100.00%2100.00%

/* * Flags is a 32-bit value that allows up to 31 non-fs dependent flags to * be given to the mount() call (ie: read-only, no-dev, no-suid etc). * * data is a (void *) that can point to any structure up to * PAGE_SIZE-1 bytes, which can contain arbitrary fs-dependent * information (or be NULL). * * Pre-0.97 versions of mount() didn't have a flags word. * When the flags word was introduced its top half was required * to have the magic value 0xC0ED, and this remained so until 2.4.0-test9. * Therefore, if this magic number is present, it carries no information * and must be discarded. */
long do_mount(const char *dev_name, const char __user *dir_name, const char *type_page, unsigned long flags, void *data_page) { struct path path; int retval = 0; int mnt_flags = 0; /* Discard magic */ if ((flags & MS_MGC_MSK) == MS_MGC_VAL) flags &= ~MS_MGC_MSK; /* Basic sanity checks */ if (data_page) ((char *)data_page)[PAGE_SIZE - 1] = 0; /* ... and get the mountpoint */ retval = user_path(dir_name, &path); if (retval) return retval; retval = security_sb_mount(dev_name, &path, type_page, flags, data_page); if (!retval && !may_mount()) retval = -EPERM; if (!retval && (flags & MS_MANDLOCK) && !may_mandlock()) retval = -EPERM; if (retval) goto dput_out; /* Default to relatime unless overriden */ if (!(flags & MS_NOATIME)) mnt_flags |= MNT_RELATIME; /* Separate the per-mountpoint flags */ if (flags & MS_NOSUID) mnt_flags |= MNT_NOSUID; if (flags & MS_NODEV) mnt_flags |= MNT_NODEV; if (flags & MS_NOEXEC) mnt_flags |= MNT_NOEXEC; if (flags & MS_NOATIME) mnt_flags |= MNT_NOATIME; if (flags & MS_NODIRATIME) mnt_flags |= MNT_NODIRATIME; if (flags & MS_STRICTATIME) mnt_flags &= ~(MNT_RELATIME | MNT_NOATIME); if (flags & MS_RDONLY) mnt_flags |= MNT_READONLY; /* The default atime for remount is preservation */ if ((flags & MS_REMOUNT) && ((flags & (MS_NOATIME | MS_NODIRATIME | MS_RELATIME | MS_STRICTATIME)) == 0)) { mnt_flags &= ~MNT_ATIME_MASK; mnt_flags |= path.mnt->mnt_flags & MNT_ATIME_MASK; } flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE | MS_BORN | MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT | MS_STRICTATIME | MS_NOREMOTELOCK); if (flags & MS_REMOUNT) retval = do_remount(&path, flags & ~MS_REMOUNT, mnt_flags, data_page); else if (flags & MS_BIND) retval = do_loopback(&path, dev_name, flags & MS_REC); else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE)) retval = do_change_type(&path, flags); else if (flags & MS_MOVE) retval = do_move_mount(&path, dev_name); else retval = do_new_mount(&path, type_page, flags, mnt_flags, dev_name, data_page); dput_out: path_put(&path); return retval; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds17841.30%310.00%
eric w. biedermaneric w. biederman4410.21%13.33%
tetsuo handatetsuo handa368.35%13.33%
al viroal viro327.42%620.00%
christoph hellwigchristoph hellwig245.57%13.33%
ram pairam pai245.57%413.33%
matthew garrettmatthew garrett214.87%26.67%
jeff laytonjeff layton204.64%13.33%
andrew mortonandrew morton194.41%26.67%
andi kleenandi kleen102.32%13.33%
valerie hensonvalerie henson61.39%13.33%
dave hansendave hansen61.39%13.33%
miklos szeredimiklos szeredi20.46%13.33%
seunghun leeseunghun lee20.46%13.33%
pavel emelianovpavel emelianov20.46%13.33%
jan blunckjan blunck20.46%13.33%
stephen d. smalleystephen d. smalley20.46%13.33%
david howellsdavid howells10.23%13.33%
Total431100.00%30100.00%


static struct ucounts *inc_mnt_namespaces(struct user_namespace *ns) { return inc_ucount(ns, current_euid(), UCOUNT_MNT_NAMESPACES); }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman24100.00%1100.00%
Total24100.00%1100.00%


static void dec_mnt_namespaces(struct ucounts *ucounts) { dec_ucount(ucounts, UCOUNT_MNT_NAMESPACES); }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman18100.00%1100.00%
Total18100.00%1100.00%


static void free_mnt_ns(struct mnt_namespace *ns) { ns_free_inum(&ns->ns); dec_mnt_namespaces(ns->ucounts); put_user_ns(ns->user_ns); kfree(ns); }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman3592.11%360.00%
al viroal viro37.89%240.00%
Total38100.00%5100.00%

/* * Assign a sequence number so we can detect when we attempt to bind * mount a reference to an older mount namespace into the current * mount namespace, preventing reference counting loops. A 64bit * number incrementing at 10Ghz will take 12,427 years to wrap which * is effectively never, so we can ignore the possibility. */ static atomic64_t mnt_ns_seq = ATOMIC64_INIT(1);
static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns) { struct mnt_namespace *new_ns; struct ucounts *ucounts; int ret; ucounts = inc_mnt_namespaces(user_ns); if (!ucounts) return ERR_PTR(-ENOSPC); new_ns = kmalloc(sizeof(struct mnt_namespace), GFP_KERNEL); if (!new_ns) { dec_mnt_namespaces(ucounts); return ERR_PTR(-ENOMEM); } ret = ns_alloc_inum(&new_ns->ns); if (ret) { kfree(new_ns); dec_mnt_namespaces(ucounts); return ERR_PTR(ret); } new_ns->ns.ops = &mntns_operations; new_ns->seq = atomic64_add_return(1, &mnt_ns_seq); atomic_set(&new_ns->count, 1); new_ns->root = NULL; INIT_LIST_HEAD(&new_ns->list); init_waitqueue_head(&new_ns->poll); new_ns->event = 0; new_ns->user_ns = get_user_ns(user_ns); new_ns->ucounts = ucounts; new_ns->mounts = 0; new_ns->pending_mounts = 0; return new_ns; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman10754.04%633.33%
linus torvaldslinus torvalds4221.21%211.11%
al viroal viro2512.63%422.22%
trond myklebusttrond myklebust115.56%15.56%
cedric le goatercedric le goater52.53%15.56%
kirill korotaevkirill korotaev31.52%15.56%
adrian bunkadrian bunk21.01%15.56%
janak desaijanak desai21.01%15.56%
badari pulavartybadari pulavarty10.51%15.56%
Total198100.00%18100.00%


__latent_entropy struct mnt_namespace *copy_mnt_ns(unsigned long flags, struct mnt_namespace *ns, struct user_namespace *user_ns, struct fs_struct *new_fs) { struct mnt_namespace *new_ns; struct vfsmount *rootmnt = NULL, *pwdmnt = NULL; struct mount *p, *q; struct mount *old; struct mount *new; int copy_flags; BUG_ON(!ns); if (likely(!(flags & CLONE_NEWNS))) { get_mnt_ns(ns); return ns; } old = ns->root; new_ns = alloc_mnt_ns(user_ns); if (IS_ERR(new_ns)) return new_ns; namespace_lock(); /* First pass: copy the tree topology */ copy_flags = CL_COPY_UNBINDABLE | CL_EXPIRE; if (user_ns != ns->user_ns) copy_flags |= CL_SHARED_TO_SLAVE | CL_UNPRIVILEGED; new = copy_tree(old, old->mnt.mnt_root, copy_flags); if (IS_ERR(new)) { namespace_unlock(); free_mnt_ns(new_ns); return ERR_CAST(new); } new_ns->root = new; list_add_tail(&new_ns->list, &new->mnt_list); /* * Second pass: switch the tsk->fs->* elements and mark new vfsmounts * as belonging to new namespace. We have already acquired a private * fs_struct, so tsk->fs->lock is not needed. */ p = old; q = new; while (p) { q->mnt_ns = new_ns; new_ns->mounts++; if (new_fs) { if (&p->mnt == new_fs->root.mnt) { new_fs->root.mnt = mntget(&q->mnt); rootmnt = &p->mnt; } if (&p->mnt == new_fs->pwd.mnt) { new_fs->pwd.mnt = mntget(&q->mnt); pwdmnt = &p->mnt; } } p = next_mnt(p, old); q = next_mnt(q, new); if (!q) break; while (p->mnt.mnt_root != q->mnt.mnt_root) p = next_mnt(p, old); } namespace_unlock(); if (rootmnt) mntput(rootmnt); if (pwdmnt) mntput(pwdmnt); return new_ns; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro12232.80%936.00%
linus torvaldslinus torvalds9525.54%14.00%
eric w. biedermaneric w. biederman6617.74%520.00%
trond myklebusttrond myklebust5113.71%14.00%
jan blunckjan blunck123.23%14.00%
andrew mortonandrew morton102.69%14.00%
david howellsdavid howells51.34%14.00%
janak desaijanak desai41.08%14.00%
adrian bunkadrian bunk20.54%14.00%
cedric le goatercedric le goater20.54%14.00%
kirill korotaevkirill korotaev10.27%14.00%
ram pairam pai10.27%14.00%
emese revfyemese revfy10.27%14.00%
Total372100.00%25100.00%

/** * create_mnt_ns - creates a private namespace and adds a root filesystem * @mnt: pointer to the new root filesystem mountpoint */
static struct mnt_namespace *create_mnt_ns(struct vfsmount *m) { struct mnt_namespace *new_ns = alloc_mnt_ns(&init_user_ns); if (!IS_ERR(new_ns)) { struct mount *mnt = real_mount(m); mnt->mnt_ns = new_ns; new_ns->root = mnt; new_ns->mounts++; list_add(&mnt->mnt_list, &new_ns->list); } else { mntput(m); } return new_ns; }

Contributors

PersonTokensPropCommitsCommitProp
trond myklebusttrond myklebust4856.47%111.11%
al viroal viro2832.94%666.67%
eric w. biedermaneric w. biederman910.59%222.22%
Total85100.00%9100.00%


struct dentry *mount_subtree(struct vfsmount *mnt, const char *name) { struct mnt_namespace *ns; struct super_block *s; struct path path; int err; ns = create_mnt_ns(mnt); if (IS_ERR(ns)) return ERR_CAST(ns); err = vfs_path_lookup(mnt->mnt_root, mnt, name, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path); put_mnt_ns(ns); if (err) return ERR_PTR(err); /* trade a vfsmount reference for active sb one */ s = path.mnt->mnt_sb; atomic_inc(&s->s_active); mntput(path.mnt); /* lock the sucker */ down_write(&s->s_umount); /* ... and return the root of (sub)tree on it */ return path.dentry; }

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PersonTokensPropCommitsCommitProp
al viroal viro128100.00%2100.00%
Total128100.00%2100.00%

EXPORT_SYMBOL(mount_subtree); SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name, char __user *, type, unsigned long, flags, void __user *, data) { int ret; char *kernel_type; char *kernel_dev; void *options; kernel_type = copy_mount_string(type); ret = PTR_ERR(kernel_type); if (IS_ERR(kernel_type)) goto out_type; kernel_dev = copy_mount_string(dev_name); ret = PTR_ERR(kernel_dev); if (IS_ERR(kernel_dev)) goto out_dev; options = copy_mount_options(data); ret = PTR_ERR(options); if (IS_ERR(options)) goto out_data; ret = do_mount(kernel_dev, dir_name, kernel_type, flags, options); kfree(options); out_data: kfree(kernel_dev); out_dev: kfree(kernel_type); out_type: return ret; } /* * Return true if path is reachable from root * * namespace_sem or mount_lock is held */
bool is_path_reachable(struct mount *mnt, struct dentry *dentry, const struct path *root) { while (&mnt->mnt != root->mnt && mnt_has_parent(mnt)) { dentry = mnt->mnt_mountpoint; mnt = mnt->mnt_parent; } return &mnt->mnt == root->mnt && is_subdir(dentry, root->dentry); }

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PersonTokensPropCommitsCommitProp
al viroal viro70100.00%2100.00%
Total70100.00%2100.00%


bool path_is_under(const struct path *path1, const struct path *path2) { bool res; read_seqlock_excl(&mount_lock); res = is_path_reachable(real_mount(path1->mnt), path1->dentry, path2); read_sequnlock_excl(&mount_lock); return res; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro4788.68%350.00%
yaowei baiyaowei bai23.77%116.67%
andi kleenandi kleen23.77%116.67%
mickael salaunmickael salaun23.77%116.67%
Total53100.00%6100.00%

EXPORT_SYMBOL(path_is_under); /* * pivot_root Semantics: * Moves the root file system of the current process to the directory put_old, * makes new_root as the new root file system of the current process, and sets * root/cwd of all processes which had them on the current root to new_root. * * Restrictions: * The new_root and put_old must be directories, and must not be on the * same file system as the current process root. The put_old must be * underneath new_root, i.e. adding a non-zero number of /.. to the string * pointed to by put_old must yield the same directory as new_root. No other * file system may be mounted on put_old. After all, new_root is a mountpoint. * * Also, the current root cannot be on the 'rootfs' (initial ramfs) filesystem. * See Documentation/filesystems/ramfs-rootfs-initramfs.txt for alternatives * in this situation. * * Notes: * - we don't move root/cwd if they are not at the root (reason: if something * cared enough to change them, it's probably wrong to force them elsewhere) * - it's okay to pick a root that isn't the root of a file system, e.g. * /nfs/my_root where /nfs is the mount point. It must be a mountpoint, * though, so you may need to say mount --bind /nfs/my_root /nfs/my_root * first. */ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, const char __user *, put_old) { struct path new, old, parent_path, root_parent, root; struct mount *new_mnt, *root_mnt, *old_mnt; struct mountpoint *old_mp, *root_mp; int error; if (!may_mount()) return -EPERM; error = user_path_dir(new_root, &new); if (error) goto out0; error = user_path_dir(put_old, &old); if (error) goto out1; error = security_sb_pivotroot(&old, &new); if (error) goto out2; get_fs_root(current->fs, &root); old_mp = lock_mount(&old); error = PTR_ERR(old_mp); if (IS_ERR(old_mp)) goto out3; error = -EINVAL; new_mnt = real_mount(new.mnt); root_mnt = real_mount(root.mnt); old_mnt = real_mount(old.mnt); if (IS_MNT_SHARED(old_mnt) || IS_MNT_SHARED(new_mnt->mnt_parent) || IS_MNT_SHARED(root_mnt->mnt_parent)) goto out4; if (!check_mnt(root_mnt) || !check_mnt(new_mnt)) goto out4; if (new_mnt->mnt.mnt_flags & MNT_LOCKED) goto out4; error = -ENOENT; if (d_unlinked(new.dentry)) goto out4; error = -EBUSY; if (new_mnt == root_mnt || old_mnt == root_mnt) goto out4; /* loop, on the same file system */ error = -EINVAL; if (root.mnt->mnt_root != root.dentry) goto out4; /* not a mountpoint */ if (!mnt_has_parent(root_mnt)) goto out4; /* not attached */ root_mp = root_mnt->mnt_mp; if (new.mnt->mnt_root != new.dentry) goto out4; /* not a mountpoint */ if (!mnt_has_parent(new_mnt)) goto out4; /* not attached */ /* make sure we can reach put_old from new_root */ if (!is_path_reachable(old_mnt, old.dentry, &new)) goto out4; /* make certain new is below the root */ if (!is_path_reachable(new_mnt, new.dentry, &root)) goto out4; root_mp->m_count++; /* pin it so it won't go away */ lock_mount_hash(); detach_mnt(new_mnt, &parent_path); detach_mnt(root_mnt, &root_parent); if (root_mnt->mnt.mnt_flags & MNT_LOCKED) { new_mnt->mnt.mnt_flags |= MNT_LOCKED; root_mnt->mnt.mnt_flags &= ~MNT_LOCKED; } /* mount old root on put_old */ attach_mnt(root_mnt, old_mnt, old_mp); /* mount new_root on / */ attach_mnt(new_mnt, real_mount(root_parent.mnt), root_mp); touch_mnt_namespace(current->nsproxy->mnt_ns); /* A moved mount should not expire automatically */ list_del_init(&new_mnt->mnt_expire); put_mountpoint(root_mp); unlock_mount_hash(); chroot_fs_refs(&root, &new); error = 0; out4: unlock_mount(old_mp); if (!error) { path_put(&root_parent); path_put(&parent_path); } out3: path_put(&root); out2: path_put(&old); out1: path_put(&new); out0: return error; }
static void __init init_mount_tree(void) { struct vfsmount *mnt; struct mnt_namespace *ns; struct path root; struct file_system_type *type; type = get_fs_type("rootfs"); if (!type) panic("Can't find rootfs type"); mnt = vfs_kern_mount(type, 0, "rootfs", NULL); put_filesystem(type); if (IS_ERR(mnt)) panic("Can't create rootfs"); ns = create_mnt_ns(mnt); if (IS_ERR(ns)) panic("Can't allocate initial namespace"); init_task.nsproxy->mnt_ns = ns; get_mnt_ns(ns); root.mnt = mnt; root.dentry = mnt->mnt_root; mnt->mnt_flags |= MNT_LOCKED; set_fs_pwd(current->fs, &root); set_fs_root(current->fs, &root); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds7248.98%330.00%
eric w. biedermaneric w. biederman3523.81%220.00%
jan blunckjan blunck2315.65%110.00%
kirill korotaevkirill korotaev85.44%110.00%
trond myklebusttrond myklebust53.40%110.00%
serge hallynserge hallyn21.36%110.00%
al viroal viro21.36%110.00%
Total147100.00%10100.00%


void __init mnt_init(void) { unsigned u; int err; mnt_cache = kmem_cache_create("mnt_cache", sizeof(struct mount), 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL); mount_hashtable = alloc_large_system_hash("Mount-cache", sizeof(struct hlist_head), mhash_entries, 19, 0, &m_hash_shift, &m_hash_mask, 0, 0); mountpoint_hashtable = alloc_large_system_hash("Mountpoint-cache", sizeof(struct hlist_head), mphash_entries, 19, 0, &mp_hash_shift, &mp_hash_mask, 0, 0); if (!mount_hashtable || !mountpoint_hashtable) panic("Failed to allocate mount hash table\n"); for (u = 0; u <= m_hash_mask; u++) INIT_HLIST_HEAD(&mount_hashtable[u]); for (u = 0; u <= mp_hash_mask; u++) INIT_HLIST_HEAD(&mountpoint_hashtable[u]); kernfs_init(); err = sysfs_init(); if (err) printk(KERN_WARNING "%s: sysfs_init error: %d\n", __func__, err); fs_kobj = kobject_create_and_add("fs", NULL); if (!fs_kobj) printk(KERN_WARNING "%s: kobj create error\n", __func__); init_rootfs(); init_mount_tree(); }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro7939.50%425.00%
linus torvaldslinus torvalds5427.00%212.50%
randy dunlaprandy dunlap2814.00%16.25%
eric dumazeteric dumazet178.50%16.25%
greg kroah-hartmangreg kroah-hartman84.00%16.25%
patrick mochelpatrick mochel31.50%212.50%
tejun heotejun heo31.50%16.25%
miklos szeredimiklos szeredi31.50%16.25%
harvey harrisonharvey harrison21.00%16.25%
andrew mortonandrew morton21.00%16.25%
cheng renquancheng renquan10.50%16.25%
Total200100.00%16100.00%


void put_mnt_ns(struct mnt_namespace *ns) { if (!atomic_dec_and_test(&ns->count)) return; drop_collected_mounts(&ns->root->mnt); free_mnt_ns(ns); }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton1437.84%114.29%
trond myklebusttrond myklebust1232.43%114.29%
al viroal viro616.22%228.57%
kirill korotaevkirill korotaev38.11%114.29%
eric w. biedermaneric w. biederman12.70%114.29%
andi kleenandi kleen12.70%114.29%
Total37100.00%7100.00%


struct vfsmount *kern_mount_data(struct file_system_type *type, void *data) { struct vfsmount *mnt; mnt = vfs_kern_mount(type, MS_KERNMOUNT, type->name, data); if (!IS_ERR(mnt)) { /* * it is a longterm mount, don't release mnt until * we unmount before file sys is unregistered */ real_mount(mnt)->mnt_ns = MNT_NS_INTERNAL; } return mnt; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro3457.63%266.67%
tim chentim chen2542.37%133.33%
Total59100.00%3100.00%

EXPORT_SYMBOL_GPL(kern_mount_data);
void kern_unmount(struct vfsmount *mnt) { /* release long term mount so mount point can be released */ if (!IS_ERR_OR_NULL(mnt)) { real_mount(mnt)->mnt_ns = NULL; synchronize_rcu(); /* yecchhh... */ mntput(mnt); } }

Contributors

PersonTokensPropCommitsCommitProp
tim chentim chen3076.92%125.00%
al viroal viro923.08%375.00%
Total39100.00%4100.00%

EXPORT_SYMBOL(kern_unmount);
bool our_mnt(struct vfsmount *mnt) { return check_mnt(real_mount(mnt)); }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro19100.00%2100.00%
Total19100.00%2100.00%


bool current_chrooted(void) { /* Does the current process have a non-standard root */ struct path ns_root; struct path fs_root; bool chrooted; /* Find the namespace root */ ns_root.mnt = &current->nsproxy->mnt_ns->root->mnt; ns_root.dentry = ns_root.mnt->mnt_root; path_get(&ns_root); while (d_mountpoint(ns_root.dentry) && follow_down_one(&ns_root)) ; get_fs_root(current->fs, &fs_root); chrooted = !path_equal(&fs_root, &ns_root); path_put(&fs_root); path_put(&ns_root); return chrooted; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman104100.00%1100.00%
Total104100.00%1100.00%


static bool mnt_already_visible(struct mnt_namespace *ns, struct vfsmount *new, int *new_mnt_flags) { int new_flags = *new_mnt_flags; struct mount *mnt; bool visible = false; down_read(&namespace_sem); list_for_each_entry(mnt, &ns->list, mnt_list) { struct mount *child; int mnt_flags; if (mnt->mnt.mnt_sb->s_type != new->mnt_sb->s_type) continue; /* This mount is not fully visible if it's root directory * is not the root directory of the filesystem. */ if (mnt->mnt.mnt_root != mnt->mnt.mnt_sb->s_root) continue; /* A local view of the mount flags */ mnt_flags = mnt->mnt.mnt_flags; /* Don't miss readonly hidden in the superblock flags */ if (mnt->mnt.mnt_sb->s_flags & MS_RDONLY) mnt_flags |= MNT_LOCK_READONLY; /* Verify the mount flags are equal to or more permissive * than the proposed new mount. */ if ((mnt_flags & MNT_LOCK_READONLY) && !(new_flags & MNT_READONLY)) continue; if ((mnt_flags & MNT_LOCK_ATIME) && ((mnt_flags & MNT_ATIME_MASK) != (new_flags & MNT_ATIME_MASK))) continue; /* This mount is not fully visible if there are any * locked child mounts that cover anything except for * empty directories. */ list_for_each_entry(child, &mnt->mnt_mounts, mnt_child) { struct inode *inode = child->mnt_mountpoint->d_inode; /* Only worry about locked mounts */ if (!(child->mnt.mnt_flags & MNT_LOCKED)) continue; /* Is the directory permanetly empty? */ if (!is_empty_dir_inode(inode)) goto next; } /* Preserve the locked attributes */ *new_mnt_flags |= mnt_flags & (MNT_LOCK_READONLY | \ MNT_LOCK_ATIME); visible = true; goto found; next: ; } found: up_read(&namespace_sem); return visible; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman23495.90%1292.31%
al viroal viro104.10%17.69%
Total244100.00%13100.00%


static bool mount_too_revealing(struct vfsmount *mnt, int *new_mnt_flags) { const unsigned long required_iflags = SB_I_NOEXEC | SB_I_NODEV; struct mnt_namespace *ns = current->nsproxy->mnt_ns; unsigned long s_iflags; if (ns->user_ns == &init_user_ns) return false; /* Can this filesystem be too revealing? */ s_iflags = mnt->mnt_sb->s_iflags; if (!(s_iflags & SB_I_USERNS_VISIBLE)) return false; if ((s_iflags & required_iflags) != required_iflags) { WARN_ONCE(1, "Expected s_iflags to contain 0x%lx\n", required_iflags); return true; } return !mnt_already_visible(ns, mnt, new_mnt_flags); }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman107100.00%2100.00%
Total107100.00%2100.00%


bool mnt_may_suid(struct vfsmount *mnt) { /* * Foreign mounts (accessed via fchdir or through /proc * symlinks) are always treated as if they are nosuid. This * prevents namespaces from trusting potentially unsafe * suid/sgid bits, file caps, or security labels that originate * in other namespaces. */ return !(mnt->mnt_flags & MNT_NOSUID) && check_mnt(real_mount(mnt)) && current_in_userns(mnt->mnt_sb->s_user_ns); }

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PersonTokensPropCommitsCommitProp
andy lutomirskiandy lutomirski38100.00%1100.00%
Total38100.00%1100.00%


static struct ns_common *mntns_get(struct task_struct *task) { struct ns_common *ns = NULL; struct nsproxy *nsproxy; task_lock(task); nsproxy = task->nsproxy; if (nsproxy) { ns = &nsproxy->mnt_ns->ns; get_mnt_ns(to_mnt_ns(ns)); } task_unlock(task); return ns; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman5886.57%250.00%
al viroal viro913.43%250.00%
Total67100.00%4100.00%


static void mntns_put(struct ns_common *ns) { put_mnt_ns(to_mnt_ns(ns)); }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman1473.68%133.33%
al viroal viro526.32%266.67%
Total19100.00%3100.00%


static int mntns_install(struct nsproxy *nsproxy, struct ns_common *ns) { struct fs_struct *fs = current->fs; struct mnt_namespace *mnt_ns = to_mnt_ns(ns); struct path root; if (!ns_capable(mnt_ns->user_ns, CAP_SYS_ADMIN) || !ns_capable(current_user_ns(), CAP_SYS_CHROOT) || !ns_capable(current_user_ns(), CAP_SYS_ADMIN)) return -EPERM; if (fs->users != 1) return -EINVAL; get_mnt_ns(mnt_ns); put_mnt_ns(nsproxy->mnt_ns); nsproxy->mnt_ns = mnt_ns; /* Find the root */ root.mnt = &mnt_ns->root->mnt; root.dentry = mnt_ns->root->mnt.mnt_root; path_get(&root); while(d_mountpoint(root.dentry) && follow_down_one(&root)) ; /* Update the pwd and root */ set_fs_pwd(fs, &root); set_fs_root(fs, &root); path_put(&root); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman16996.57%457.14%
al viroal viro52.86%228.57%
zhao hongjiangzhao hongjiang10.57%114.29%
Total175100.00%7100.00%


static struct user_namespace *mntns_owner(struct ns_common *ns) { return to_mnt_ns(ns)->user_ns; }

Contributors

PersonTokensPropCommitsCommitProp
andrey vaginandrey vagin21100.00%1100.00%
Total21100.00%1100.00%

const struct proc_ns_operations mntns_operations = { .name = "mnt", .type = CLONE_NEWNS, .get = mntns_get, .put = mntns_put, .install = mntns_install, .owner = mntns_owner, };

Overall Contributors

PersonTokensPropCommitsCommitProp
al viroal viro464632.36%13638.42%
eric w. biedermaneric w. biederman279019.43%5716.10%
linus torvaldslinus torvalds227415.84%154.24%
miklos szeredimiklos szeredi9746.78%174.80%
ram pairam pai8365.82%143.95%
nick pigginnick piggin5163.59%61.69%
david howellsdavid howells3712.58%92.54%
trond myklebusttrond myklebust3102.16%51.41%
dave hansendave hansen2912.03%30.85%
andrew mortonandrew morton2051.43%102.82%
jan karajan kara1420.99%10.28%
jan blunckjan blunck970.68%61.69%
ian kentian kent780.54%20.56%
valerie auroravalerie aurora680.47%10.28%
tim chentim chen600.42%10.28%
heiko carstensheiko carstens560.39%20.56%
andy lutomirskiandy lutomirski500.35%20.56%
vegard nossumvegard nossum450.31%10.28%
andries brouwerandries brouwer400.28%20.56%
jeff laytonjeff layton390.27%10.28%
christoph hellwigchristoph hellwig390.27%30.85%
tetsuo handatetsuo handa360.25%10.28%
kirill korotaevkirill korotaev310.22%10.28%
randy dunlaprandy dunlap310.22%20.56%
tim gardnertim gardner280.20%10.28%
andrey vaginandrey vagin270.19%20.56%
greg kroah-hartmangreg kroah-hartman270.19%41.13%
li zefanli zefan230.16%10.28%
stephen d. smalleystephen d. smalley230.16%10.28%
matthew garrettmatthew garrett210.15%20.56%
eric dumazeteric dumazet210.15%20.56%
eric pariseric paris180.13%20.56%
andreas gruenbacherandreas gruenbacher180.13%20.56%
andi kleenandi kleen140.10%20.56%
pavel emelianovpavel emelianov130.09%20.56%
adrian bunkadrian bunk70.05%20.56%
cedric le goatercedric le goater70.05%10.28%
serge hallynserge hallyn70.05%10.28%
valerie hensonvalerie henson60.04%10.28%
janak desaijanak desai60.04%10.28%
yann droneaudyann droneaud60.04%10.28%
arnaldo carvalho de meloarnaldo carvalho de melo50.03%10.28%
roman borisovroman borisov40.03%10.28%
dan carpenterdan carpenter40.03%10.28%
andrey ulanovandrey ulanov30.02%10.28%
tejun heotejun heo30.02%10.28%
patrick mochelpatrick mochel30.02%20.56%
domen puncerdomen puncer30.02%10.28%
miao xiemiao xie30.02%10.28%
andrzej hajdaandrzej hajda30.02%10.28%
seunghun leeseunghun lee30.02%10.28%
arnd bergmannarnd bergmann30.02%10.28%
mickael salaunmickael salaun20.01%10.28%
christoph lameterchristoph lameter20.01%10.28%
prasanna medaprasanna meda20.01%10.28%
harvey harrisonharvey harrison20.01%10.28%
yaowei baiyaowei bai20.01%10.28%
chuck leverchuck lever20.01%10.28%
ken heliasken helias10.01%10.28%
robert p. j. dayrobert p. j. day10.01%10.28%
alexey dobriyanalexey dobriyan10.01%10.28%
badari pulavartybadari pulavarty10.01%10.28%
emese revfyemese revfy10.01%10.28%
rob landleyrob landley10.01%10.28%
cheng renquancheng renquan10.01%10.28%
kay sieverskay sievers10.01%10.28%
neil brownneil brown10.01%10.28%
zhao hongjiangzhao hongjiang10.01%10.28%
ravikiran g thirumalairavikiran g thirumalai0.00%00.00%
Total14356100.00%354100.00%
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