Contributors: 34
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| David Howells |
459 |
22.89% |
6 |
4.65% |
| Alexey Gladkov |
409 |
20.40% |
6 |
4.65% |
| Aleksa Sarai |
345 |
17.21% |
2 |
1.55% |
| Linus Torvalds (pre-git) |
244 |
12.17% |
35 |
27.13% |
| Vasiliy Kulikov |
163 |
8.13% |
3 |
2.33% |
| Al Viro |
106 |
5.29% |
11 |
8.53% |
| Eric W. Biedermann |
60 |
2.99% |
13 |
10.08% |
| Pavel Emelyanov |
33 |
1.65% |
1 |
0.78% |
| Art Haas |
27 |
1.35% |
1 |
0.78% |
| Alexey Dobriyan |
26 |
1.30% |
13 |
10.08% |
| Linus Torvalds |
18 |
0.90% |
8 |
6.20% |
| Richard Genoud |
16 |
0.80% |
1 |
0.78% |
| Maxim Patlasov |
16 |
0.80% |
1 |
0.78% |
| Andrew Morton |
9 |
0.45% |
3 |
2.33% |
| Christian Brauner |
8 |
0.40% |
3 |
2.33% |
| Theodore Y. Ts'o |
7 |
0.35% |
1 |
0.78% |
| Andi Kleen |
6 |
0.30% |
1 |
0.78% |
| Ingo Molnar |
6 |
0.30% |
2 |
1.55% |
| Jann Horn |
6 |
0.30% |
1 |
0.78% |
| Johannes Weiner |
5 |
0.25% |
1 |
0.78% |
| Neil Brown |
5 |
0.25% |
1 |
0.78% |
| Nicolas Dichtel |
4 |
0.20% |
1 |
0.78% |
| Adrian Bunk |
4 |
0.20% |
2 |
1.55% |
| Arnd Bergmann |
4 |
0.20% |
1 |
0.78% |
| Mika Kukkonen |
3 |
0.15% |
1 |
0.78% |
| Cédric Le Goater |
3 |
0.15% |
1 |
0.78% |
| Trond Myklebust |
3 |
0.15% |
1 |
0.78% |
| Arjan van de Ven |
2 |
0.10% |
2 |
1.55% |
| Jeff Layton |
2 |
0.10% |
1 |
0.78% |
| Jan Kara |
2 |
0.10% |
1 |
0.78% |
| Qi Zheng |
1 |
0.05% |
1 |
0.78% |
| Greg Kroah-Hartman |
1 |
0.05% |
1 |
0.78% |
| Harald Welte |
1 |
0.05% |
1 |
0.78% |
| Dave Jones |
1 |
0.05% |
1 |
0.78% |
| Total |
2005 |
|
129 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/proc/root.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* proc root directory handling functions
*/
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/sched/stat.h>
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/user_namespace.h>
#include <linux/fs_context.h>
#include <linux/mount.h>
#include <linux/pid_namespace.h>
#include <linux/fs_parser.h>
#include <linux/cred.h>
#include <linux/magic.h>
#include <linux/slab.h>
#include "internal.h"
struct proc_fs_context {
struct pid_namespace *pid_ns;
unsigned int mask;
enum proc_hidepid hidepid;
int gid;
enum proc_pidonly pidonly;
};
enum proc_param {
Opt_gid,
Opt_hidepid,
Opt_subset,
Opt_pidns,
};
static const struct fs_parameter_spec proc_fs_parameters[] = {
fsparam_u32("gid", Opt_gid),
fsparam_string("hidepid", Opt_hidepid),
fsparam_string("subset", Opt_subset),
fsparam_file_or_string("pidns", Opt_pidns),
{}
};
static inline int valid_hidepid(unsigned int value)
{
return (value == HIDEPID_OFF ||
value == HIDEPID_NO_ACCESS ||
value == HIDEPID_INVISIBLE ||
value == HIDEPID_NOT_PTRACEABLE);
}
static int proc_parse_hidepid_param(struct fs_context *fc, struct fs_parameter *param)
{
struct proc_fs_context *ctx = fc->fs_private;
struct fs_parameter_spec hidepid_u32_spec = fsparam_u32("hidepid", Opt_hidepid);
struct fs_parse_result result;
int base = (unsigned long)hidepid_u32_spec.data;
if (param->type != fs_value_is_string)
return invalf(fc, "proc: unexpected type of hidepid value\n");
if (!kstrtouint(param->string, base, &result.uint_32)) {
if (!valid_hidepid(result.uint_32))
return invalf(fc, "proc: unknown value of hidepid - %s\n", param->string);
ctx->hidepid = result.uint_32;
return 0;
}
if (!strcmp(param->string, "off"))
ctx->hidepid = HIDEPID_OFF;
else if (!strcmp(param->string, "noaccess"))
ctx->hidepid = HIDEPID_NO_ACCESS;
else if (!strcmp(param->string, "invisible"))
ctx->hidepid = HIDEPID_INVISIBLE;
else if (!strcmp(param->string, "ptraceable"))
ctx->hidepid = HIDEPID_NOT_PTRACEABLE;
else
return invalf(fc, "proc: unknown value of hidepid - %s\n", param->string);
return 0;
}
static int proc_parse_subset_param(struct fs_context *fc, char *value)
{
struct proc_fs_context *ctx = fc->fs_private;
while (value) {
char *ptr = strchr(value, ',');
if (ptr != NULL)
*ptr++ = '\0';
if (*value != '\0') {
if (!strcmp(value, "pid")) {
ctx->pidonly = PROC_PIDONLY_ON;
} else {
return invalf(fc, "proc: unsupported subset option - %s\n", value);
}
}
value = ptr;
}
return 0;
}
#ifdef CONFIG_PID_NS
static int proc_parse_pidns_param(struct fs_context *fc,
struct fs_parameter *param,
struct fs_parse_result *result)
{
struct proc_fs_context *ctx = fc->fs_private;
struct pid_namespace *target, *active = task_active_pid_ns(current);
struct ns_common *ns;
struct file *ns_filp __free(fput) = NULL;
switch (param->type) {
case fs_value_is_file:
/* came through fsconfig, steal the file reference */
ns_filp = no_free_ptr(param->file);
break;
case fs_value_is_string:
ns_filp = filp_open(param->string, O_RDONLY, 0);
break;
default:
WARN_ON_ONCE(true);
break;
}
if (!ns_filp)
ns_filp = ERR_PTR(-EBADF);
if (IS_ERR(ns_filp)) {
errorfc(fc, "could not get file from pidns argument");
return PTR_ERR(ns_filp);
}
if (!proc_ns_file(ns_filp))
return invalfc(fc, "pidns argument is not an nsfs file");
ns = get_proc_ns(file_inode(ns_filp));
if (ns->ns_type != CLONE_NEWPID)
return invalfc(fc, "pidns argument is not a pidns file");
target = container_of(ns, struct pid_namespace, ns);
/*
* pidns= is shorthand for joining the pidns to get a fsopen fd, so the
* permission model should be the same as pidns_install().
*/
if (!ns_capable(target->user_ns, CAP_SYS_ADMIN)) {
errorfc(fc, "insufficient permissions to set pidns");
return -EPERM;
}
if (!pidns_is_ancestor(target, active))
return invalfc(fc, "cannot set pidns to non-descendant pidns");
put_pid_ns(ctx->pid_ns);
ctx->pid_ns = get_pid_ns(target);
put_user_ns(fc->user_ns);
fc->user_ns = get_user_ns(ctx->pid_ns->user_ns);
return 0;
}
#endif /* CONFIG_PID_NS */
static int proc_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
struct proc_fs_context *ctx = fc->fs_private;
struct fs_parse_result result;
int opt, err;
opt = fs_parse(fc, proc_fs_parameters, param, &result);
if (opt < 0)
return opt;
switch (opt) {
case Opt_gid:
ctx->gid = result.uint_32;
break;
case Opt_hidepid:
err = proc_parse_hidepid_param(fc, param);
if (err)
return err;
break;
case Opt_subset:
err = proc_parse_subset_param(fc, param->string);
if (err)
return err;
break;
case Opt_pidns:
#ifdef CONFIG_PID_NS
/*
* We would have to RCU-protect every proc_pid_ns() or
* proc_sb_info() access if we allowed this to be reconfigured
* for an existing procfs instance. Luckily, procfs instances
* are cheap to create, and mount-beneath would let you
* atomically replace an instance even with overmounts.
*/
if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
errorfc(fc, "cannot reconfigure pidns for existing procfs");
return -EBUSY;
}
err = proc_parse_pidns_param(fc, param, &result);
if (err)
return err;
break;
#else
errorfc(fc, "pidns mount flag not supported on this system");
return -EOPNOTSUPP;
#endif
default:
return -EINVAL;
}
ctx->mask |= 1 << opt;
return 0;
}
static void proc_apply_options(struct proc_fs_info *fs_info,
struct fs_context *fc,
struct user_namespace *user_ns)
{
struct proc_fs_context *ctx = fc->fs_private;
if (ctx->mask & (1 << Opt_gid))
fs_info->pid_gid = make_kgid(user_ns, ctx->gid);
if (ctx->mask & (1 << Opt_hidepid))
fs_info->hide_pid = ctx->hidepid;
if (ctx->mask & (1 << Opt_subset))
fs_info->pidonly = ctx->pidonly;
if (ctx->mask & (1 << Opt_pidns) &&
!WARN_ON_ONCE(fc->purpose == FS_CONTEXT_FOR_RECONFIGURE)) {
put_pid_ns(fs_info->pid_ns);
fs_info->pid_ns = get_pid_ns(ctx->pid_ns);
}
}
static int proc_fill_super(struct super_block *s, struct fs_context *fc)
{
struct proc_fs_context *ctx = fc->fs_private;
struct inode *root_inode;
struct proc_fs_info *fs_info;
int ret;
fs_info = kzalloc(sizeof(*fs_info), GFP_KERNEL);
if (!fs_info)
return -ENOMEM;
fs_info->pid_ns = get_pid_ns(ctx->pid_ns);
proc_apply_options(fs_info, fc, current_user_ns());
/* User space would break if executables or devices appear on proc */
s->s_iflags |= SB_I_USERNS_VISIBLE | SB_I_NOEXEC | SB_I_NODEV;
s->s_flags |= SB_NODIRATIME | SB_NOSUID | SB_NOEXEC;
s->s_blocksize = 1024;
s->s_blocksize_bits = 10;
s->s_magic = PROC_SUPER_MAGIC;
s->s_op = &proc_sops;
s->s_time_gran = 1;
s->s_fs_info = fs_info;
/*
* procfs isn't actually a stacking filesystem; however, there is
* too much magic going on inside it to permit stacking things on
* top of it
*/
s->s_stack_depth = FILESYSTEM_MAX_STACK_DEPTH;
/* procfs dentries and inodes don't require IO to create */
s->s_shrink->seeks = 0;
pde_get(&proc_root);
root_inode = proc_get_inode(s, &proc_root);
if (!root_inode) {
pr_err("proc_fill_super: get root inode failed\n");
return -ENOMEM;
}
s->s_root = d_make_root(root_inode);
if (!s->s_root) {
pr_err("proc_fill_super: allocate dentry failed\n");
return -ENOMEM;
}
ret = proc_setup_self(s);
if (ret) {
return ret;
}
return proc_setup_thread_self(s);
}
static int proc_reconfigure(struct fs_context *fc)
{
struct super_block *sb = fc->root->d_sb;
struct proc_fs_info *fs_info = proc_sb_info(sb);
sync_filesystem(sb);
proc_apply_options(fs_info, fc, current_user_ns());
return 0;
}
static int proc_get_tree(struct fs_context *fc)
{
return get_tree_nodev(fc, proc_fill_super);
}
static void proc_fs_context_free(struct fs_context *fc)
{
struct proc_fs_context *ctx = fc->fs_private;
put_pid_ns(ctx->pid_ns);
kfree(ctx);
}
static const struct fs_context_operations proc_fs_context_ops = {
.free = proc_fs_context_free,
.parse_param = proc_parse_param,
.get_tree = proc_get_tree,
.reconfigure = proc_reconfigure,
};
static int proc_init_fs_context(struct fs_context *fc)
{
struct proc_fs_context *ctx;
ctx = kzalloc(sizeof(struct proc_fs_context), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
ctx->pid_ns = get_pid_ns(task_active_pid_ns(current));
put_user_ns(fc->user_ns);
fc->user_ns = get_user_ns(ctx->pid_ns->user_ns);
fc->fs_private = ctx;
fc->ops = &proc_fs_context_ops;
return 0;
}
static void proc_kill_sb(struct super_block *sb)
{
struct proc_fs_info *fs_info = proc_sb_info(sb);
if (!fs_info) {
kill_anon_super(sb);
return;
}
dput(fs_info->proc_self);
dput(fs_info->proc_thread_self);
kill_anon_super(sb);
put_pid_ns(fs_info->pid_ns);
kfree_rcu(fs_info, rcu);
}
static struct file_system_type proc_fs_type = {
.name = "proc",
.init_fs_context = proc_init_fs_context,
.parameters = proc_fs_parameters,
.kill_sb = proc_kill_sb,
.fs_flags = FS_USERNS_MOUNT | FS_DISALLOW_NOTIFY_PERM,
};
void __init proc_root_init(void)
{
proc_init_kmemcache();
set_proc_pid_nlink();
proc_self_init();
proc_thread_self_init();
proc_symlink("mounts", NULL, "self/mounts");
proc_net_init();
proc_mkdir("fs", NULL);
proc_mkdir("driver", NULL);
proc_create_mount_point("fs/nfsd"); /* somewhere for the nfsd filesystem to be mounted */
#if defined(CONFIG_SUN_OPENPROMFS) || defined(CONFIG_SUN_OPENPROMFS_MODULE)
/* just give it a mountpoint */
proc_create_mount_point("openprom");
#endif
proc_tty_init();
proc_mkdir("bus", NULL);
proc_sys_init();
/*
* Last things last. It is not like userspace processes eager
* to open /proc files exist at this point but register last
* anyway.
*/
register_filesystem(&proc_fs_type);
}
static int proc_root_getattr(struct mnt_idmap *idmap,
const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(path->dentry),
stat);
stat->nlink = proc_root.nlink + nr_processes();
return 0;
}
static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry, unsigned int flags)
{
if (!proc_pid_lookup(dentry, flags))
return NULL;
return proc_lookup(dir, dentry, flags);
}
static int proc_root_readdir(struct file *file, struct dir_context *ctx)
{
if (ctx->pos < FIRST_PROCESS_ENTRY) {
int error = proc_readdir(file, ctx);
if (unlikely(error <= 0))
return error;
ctx->pos = FIRST_PROCESS_ENTRY;
}
return proc_pid_readdir(file, ctx);
}
/*
* The root /proc directory is special, as it has the
* <pid> directories. Thus we don't use the generic
* directory handling functions for that..
*/
static const struct file_operations proc_root_operations = {
.read = generic_read_dir,
.iterate_shared = proc_root_readdir,
.llseek = generic_file_llseek,
};
/*
* proc root can do almost nothing..
*/
static const struct inode_operations proc_root_inode_operations = {
.lookup = proc_root_lookup,
.getattr = proc_root_getattr,
};
/*
* This is the root "inode" in the /proc tree..
*/
struct proc_dir_entry proc_root = {
.low_ino = PROCFS_ROOT_INO,
.namelen = 5,
.mode = S_IFDIR | S_IRUGO | S_IXUGO,
.nlink = 2,
.refcnt = REFCOUNT_INIT(1),
.proc_iops = &proc_root_inode_operations,
.proc_dir_ops = &proc_root_operations,
.parent = &proc_root,
.subdir = RB_ROOT,
.name = "/proc",
};