cregit-Linux how code gets into the kernel

Release 4.13 ipc/msg.c

Directory: ipc
/*
 * linux/ipc/msg.c
 * Copyright (C) 1992 Krishna Balasubramanian
 *
 * Removed all the remaining kerneld mess
 * Catch the -EFAULT stuff properly
 * Use GFP_KERNEL for messages as in 1.2
 * Fixed up the unchecked user space derefs
 * Copyright (C) 1998 Alan Cox & Andi Kleen
 *
 * /proc/sysvipc/msg support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
 *
 * mostly rewritten, threaded and wake-one semantics added
 * MSGMAX limit removed, sysctl's added
 * (c) 1999 Manfred Spraul <manfred@colorfullife.com>
 *
 * support for audit of ipc object properties and permission changes
 * Dustin Kirkland <dustin.kirkland@us.ibm.com>
 *
 * namespaces support
 * OpenVZ, SWsoft Inc.
 * Pavel Emelianov <xemul@openvz.org>
 */

#include <linux/capability.h>
#include <linux/msg.h>
#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/list.h>
#include <linux/security.h>
#include <linux/sched/wake_q.h>
#include <linux/syscalls.h>
#include <linux/audit.h>
#include <linux/seq_file.h>
#include <linux/rwsem.h>
#include <linux/nsproxy.h>
#include <linux/ipc_namespace.h>

#include <asm/current.h>
#include <linux/uaccess.h>
#include "util.h"

/* one msg_receiver structure for each sleeping receiver */

struct msg_receiver {
	
struct list_head	r_list;
	
struct task_struct	*r_tsk;

	
int			r_mode;
	
long			r_msgtype;
	
long			r_maxsize;

	
struct msg_msg		*r_msg;
};

/* one msg_sender for each sleeping sender */

struct msg_sender {
	
struct list_head	list;
	
struct task_struct	*tsk;
	
size_t                  msgsz;
};


#define SEARCH_ANY		1

#define SEARCH_EQUAL		2

#define SEARCH_NOTEQUAL		3

#define SEARCH_LESSEQUAL	4

#define SEARCH_NUMBER		5


#define msg_ids(ns)	((ns)->ids[IPC_MSG_IDS])


static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_obtain_object_idr(&msg_ids(ns), id); if (IS_ERR(ipcp)) return ERR_CAST(ipcp); return container_of(ipcp, struct msg_queue, q_perm); }

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Davidlohr Bueso A57100.00%2100.00%
Total57100.00%2100.00%


static inline struct msg_queue *msq_obtain_object_check(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&msg_ids(ns), id); if (IS_ERR(ipcp)) return ERR_CAST(ipcp); return container_of(ipcp, struct msg_queue, q_perm); }

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Davidlohr Bueso A57100.00%1100.00%
Total57100.00%1100.00%


static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s) { ipc_rmid(&msg_ids(ns), &s->q_perm); }

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Nadia Derbey31100.00%1100.00%
Total31100.00%1100.00%


static void msg_rcu_free(struct rcu_head *head) { struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu); struct msg_queue *msq = container_of(p, struct msg_queue, q_perm); security_msg_queue_free(msq); kvfree(msq); }

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Davidlohr Bueso A3772.55%125.00%
Manfred Spraul815.69%125.00%
Kees Cook611.76%250.00%
Total51100.00%4100.00%

/** * newque - Create a new msg queue * @ns: namespace * @params: ptr to the structure that contains the key and msgflg * * Called with msg_ids.rwsem held (writer) */
static int newque(struct ipc_namespace *ns, struct ipc_params *params) { struct msg_queue *msq; int retval; key_t key = params->key; int msgflg = params->flg; msq = kvmalloc(sizeof(*msq), GFP_KERNEL); if (unlikely(!msq)) return -ENOMEM; msq->q_perm.mode = msgflg & S_IRWXUGO; msq->q_perm.key = key; msq->q_perm.security = NULL; retval = security_msg_queue_alloc(msq); if (retval) { kvfree(msq); return retval; } msq->q_stime = msq->q_rtime = 0; msq->q_ctime = get_seconds(); msq->q_cbytes = msq->q_qnum = 0; msq->q_qbytes = ns->msg_ctlmnb; msq->q_lspid = msq->q_lrpid = 0; INIT_LIST_HEAD(&msq->q_messages); INIT_LIST_HEAD(&msq->q_receivers); INIT_LIST_HEAD(&msq->q_senders); /* ipc_addid() locks msq upon success. */ retval = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni); if (retval < 0) { call_rcu(&msq->q_perm.rcu, msg_rcu_free); return retval; } ipc_unlock_object(&msq->q_perm); rcu_read_unlock(); return msq->q_perm.id; }

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Linus Torvalds (pre-git)9639.83%420.00%
Linus Torvalds3514.52%15.00%
Greg Kroah-Hartman239.54%315.00%
Stephen D. Smalley239.54%15.00%
Nadia Derbey218.71%210.00%
Kees Cook145.81%15.00%
Manfred Spraul93.73%210.00%
Kirill Korotaev72.90%15.00%
Davidlohr Bueso A72.90%210.00%
Ingo Molnar31.24%15.00%
Andi Kleen20.83%15.00%
Andrew Morton10.41%15.00%
Total241100.00%20100.00%


static inline bool msg_fits_inqueue(struct msg_queue *msq, size_t msgsz) { return msgsz + msq->q_cbytes <= msq->q_qbytes && 1 + msq->q_qnum <= msq->q_qbytes; }

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Davidlohr Bueso A36100.00%1100.00%
Total36100.00%1100.00%


static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss, size_t msgsz) { mss->tsk = current; mss->msgsz = msgsz; __set_current_state(TASK_INTERRUPTIBLE); list_add_tail(&mss->list, &msq->q_senders); }

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Linus Torvalds (pre-git)3876.00%133.33%
Davidlohr Bueso A1224.00%266.67%
Total50100.00%3100.00%


static inline void ss_del(struct msg_sender *mss) { if (mss->list.next) list_del(&mss->list); }

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Linus Torvalds (pre-git)28100.00%1100.00%
Total28100.00%1100.00%


static void ss_wakeup(struct msg_queue *msq, struct wake_q_head *wake_q, bool kill) { struct msg_sender *mss, *t; struct task_struct *stop_tsk = NULL; struct list_head *h = &msq->q_senders; list_for_each_entry_safe(mss, t, h, list) { if (kill) mss->list.next = NULL; /* * Stop at the first task we don't wakeup, * we've already iterated the original * sender queue. */ else if (stop_tsk == mss->tsk) break; /* * We are not in an EIDRM scenario here, therefore * verify that we really need to wakeup the task. * To maintain current semantics and wakeup order, * move the sender to the tail on behalf of the * blocked task. */ else if (!msg_fits_inqueue(msq, mss->msgsz)) { if (!stop_tsk) stop_tsk = mss->tsk; list_move_tail(&mss->list, &msq->q_senders); continue; } wake_q_add(wake_q, mss->tsk); } }

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Davidlohr Bueso A8062.02%342.86%
Linus Torvalds (pre-git)3930.23%342.86%
Nikola Pajkovsky107.75%114.29%
Total129100.00%7100.00%


static void expunge_all(struct msg_queue *msq, int res, struct wake_q_head *wake_q) { struct msg_receiver *msr, *t; list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) { wake_q_add(wake_q, msr->r_tsk); WRITE_ONCE(msr->r_msg, ERR_PTR(res)); } }

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Linus Torvalds (pre-git)3050.00%350.00%
Sebastian Andrzej Siewior1220.00%116.67%
Nikola Pajkovsky1016.67%116.67%
Manfred Spraul813.33%116.67%
Total60100.00%6100.00%

/* * freeque() wakes up waiters on the sender and receiver waiting queue, * removes the message queue from message queue ID IDR, and cleans up all the * messages associated with this queue. * * msg_ids.rwsem (writer) and the spinlock for this message queue are held * before freeque() is called. msg_ids.rwsem remains locked on exit. */
static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) { struct msg_msg *msg, *t; struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm); DEFINE_WAKE_Q(wake_q); expunge_all(msq, -EIDRM, &wake_q); ss_wakeup(msq, &wake_q, true); msg_rmid(ns, msq); ipc_unlock_object(&msq->q_perm); wake_up_q(&wake_q); rcu_read_unlock(); list_for_each_entry_safe(msg, t, &msq->q_messages, m_list) { atomic_dec(&ns->msg_hdrs); free_msg(msg); } atomic_sub(msq->q_cbytes, &ns->msg_bytes); ipc_rcu_putref(&msq->q_perm, msg_rcu_free); }

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Linus Torvalds (pre-git)5741.91%421.05%
Pierre Peiffer1712.50%15.26%
Davidlohr Bueso A139.56%421.05%
Sebastian Andrzej Siewior139.56%15.26%
Nikola Pajkovsky128.82%15.26%
Kirill Korotaev118.09%210.53%
Andrew Morton75.15%210.53%
Manfred Spraul42.94%210.53%
Waiman Long10.74%15.26%
Nadia Derbey10.74%15.26%
Total136100.00%19100.00%

/* * Called with msg_ids.rwsem and ipcp locked. */
static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg) { struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm); return security_msg_queue_associate(msq, msgflg); }

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Nadia Derbey38100.00%2100.00%
Total38100.00%2100.00%

SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg) { struct ipc_namespace *ns; static const struct ipc_ops msg_ops = { .getnew = newque, .associate = msg_security, }; struct ipc_params msg_params; ns = current->nsproxy->ipc_ns; msg_params.key = key; msg_params.flg = msgflg; return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params); }
static inline unsigned long copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version) { switch (version) { case IPC_64: return copy_to_user(buf, in, sizeof(*in)); case IPC_OLD: { struct msqid_ds out; memset(&out, 0, sizeof(out)); ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm); out.msg_stime = in->msg_stime; out.msg_rtime = in->msg_rtime; out.msg_ctime = in->msg_ctime; if (in->msg_cbytes > USHRT_MAX) out.msg_cbytes = USHRT_MAX; else out.msg_cbytes = in->msg_cbytes; out.msg_lcbytes = in->msg_cbytes; if (in->msg_qnum > USHRT_MAX) out.msg_qnum = USHRT_MAX; else out.msg_qnum = in->msg_qnum; if (in->msg_qbytes > USHRT_MAX) out.msg_qbytes = USHRT_MAX; else out.msg_qbytes = in->msg_qbytes; out.msg_lqbytes = in->msg_qbytes; out.msg_lspid = in->msg_lspid; out.msg_lrpid = in->msg_lrpid; return copy_to_user(buf, &out, sizeof(out)); } default: return -EINVAL; } }

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Linus Torvalds (pre-git)21696.86%133.33%
Alexey Dobriyan62.69%133.33%
Al Viro10.45%133.33%
Total223100.00%3100.00%


static inline unsigned long copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version) { switch (version) { case IPC_64: if (copy_from_user(out, buf, sizeof(*out))) return -EFAULT; return 0; case IPC_OLD: { struct msqid_ds tbuf_old; if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) return -EFAULT; out->msg_perm.uid = tbuf_old.msg_perm.uid; out->msg_perm.gid = tbuf_old.msg_perm.gid; out->msg_perm.mode = tbuf_old.msg_perm.mode; if (tbuf_old.msg_qbytes == 0) out->msg_qbytes = tbuf_old.msg_lqbytes; else out->msg_qbytes = tbuf_old.msg_qbytes; return 0; } default: return -EINVAL; } }

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Linus Torvalds (pre-git)13691.28%133.33%
Pierre Peiffer128.05%133.33%
Al Viro10.67%133.33%
Total149100.00%3100.00%

/* * This function handles some msgctl commands which require the rwsem * to be held in write mode. * NOTE: no locks must be held, the rwsem is taken inside this function. */
static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd, struct msqid_ds __user *buf, int version) { struct kern_ipc_perm *ipcp; struct msqid64_ds uninitialized_var(msqid64); struct msg_queue *msq; int err; if (cmd == IPC_SET) { if (copy_msqid_from_user(&msqid64, buf, version)) return -EFAULT; } down_write(&msg_ids(ns).rwsem); rcu_read_lock(); ipcp = ipcctl_pre_down_nolock(ns, &msg_ids(ns), msqid, cmd, &msqid64.msg_perm, msqid64.msg_qbytes); if (IS_ERR(ipcp)) { err = PTR_ERR(ipcp); goto out_unlock1; } msq = container_of(ipcp, struct msg_queue, q_perm); err = security_msg_queue_msgctl(msq, cmd); if (err) goto out_unlock1; switch (cmd) { case IPC_RMID: ipc_lock_object(&msq->q_perm); /* freeque unlocks the ipc object and rcu */ freeque(ns, ipcp); goto out_up; case IPC_SET: { DEFINE_WAKE_Q(wake_q); if (msqid64.msg_qbytes > ns->msg_ctlmnb && !capable(CAP_SYS_RESOURCE)) { err = -EPERM; goto out_unlock1; } ipc_lock_object(&msq->q_perm); err = ipc_update_perm(&msqid64.msg_perm, ipcp); if (err) goto out_unlock0; msq->q_qbytes = msqid64.msg_qbytes; msq->q_ctime = get_seconds(); /* * Sleeping receivers might be excluded by * stricter permissions. */ expunge_all(msq, -EAGAIN, &wake_q); /* * Sleeping senders might be able to send * due to a larger queue size. */ ss_wakeup(msq, &wake_q, false); ipc_unlock_object(&msq->q_perm); wake_up_q(&wake_q); goto out_unlock1; } default: err = -EINVAL; goto out_unlock1; } out_unlock0: ipc_unlock_object(&msq->q_perm); out_unlock1: rcu_read_unlock(); out_up: up_write(&msg_ids(ns).rwsem); return err; }

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Pierre Peiffer14843.15%417.39%
Davidlohr Bueso A8625.07%521.74%
Linus Torvalds (pre-git)5215.16%417.39%
Eric W. Biedermann154.37%14.35%
Nadia Derbey144.08%14.35%
Ingo Molnar72.04%14.35%
Stephen D. Smalley61.75%14.35%
Kirill Korotaev51.46%14.35%
Felipe Contreras30.87%14.35%
Sebastian Andrzej Siewior30.87%14.35%
Serge E. Hallyn20.58%14.35%
Waiman Long10.29%14.35%
Al Viro10.29%14.35%
Total343100.00%23100.00%


static int msgctl_nolock(struct ipc_namespace *ns, int msqid, int cmd, int version, void __user *buf) { int err; struct msg_queue *msq; switch (cmd) { case IPC_INFO: case MSG_INFO: { struct msginfo msginfo; int max_id; if (!buf) return -EFAULT; /* * We must not return kernel stack data. * due to padding, it's not enough * to set all member fields. */ err = security_msg_queue_msgctl(NULL, cmd); if (err) return err; memset(&msginfo, 0, sizeof(msginfo)); msginfo.msgmni = ns->msg_ctlmni; msginfo.msgmax = ns->msg_ctlmax; msginfo.msgmnb = ns->msg_ctlmnb; msginfo.msgssz = MSGSSZ; msginfo.msgseg = MSGSEG; down_read(&msg_ids(ns).rwsem); if (cmd == MSG_INFO) { msginfo.msgpool = msg_ids(ns).in_use; msginfo.msgmap = atomic_read(&ns->msg_hdrs); msginfo.msgtql = atomic_read(&ns->msg_bytes); } else { msginfo.msgmap = MSGMAP; msginfo.msgpool = MSGPOOL; msginfo.msgtql = MSGTQL; } max_id = ipc_get_maxid(&msg_ids(ns)); up_read(&msg_ids(ns).rwsem); if (copy_to_user(buf, &msginfo, sizeof(struct msginfo))) return -EFAULT; return (max_id < 0) ? 0 : max_id; } case MSG_STAT: case IPC_STAT: { struct msqid64_ds tbuf; int success_return; if (!buf) return -EFAULT; memset(&tbuf, 0, sizeof(tbuf)); rcu_read_lock(); if (cmd == MSG_STAT) { msq = msq_obtain_object(ns, msqid); if (IS_ERR(msq)) { err = PTR_ERR(msq); goto out_unlock; } success_return = msq->q_perm.id; } else { msq = msq_obtain_object_check(ns, msqid); if (IS_ERR(msq)) { err = PTR_ERR(msq); goto out_unlock; } success_return = 0; } err = -EACCES; if (ipcperms(ns, &msq->q_perm, S_IRUGO)) goto out_unlock; err = security_msg_queue_msgctl(msq, cmd); if (err) goto out_unlock; kernel_to_ipc64_perm(&msq->q_perm, &tbuf.msg_perm); tbuf.msg_stime = msq->q_stime; tbuf.msg_rtime = msq->q_rtime; tbuf.msg_ctime = msq->q_ctime; tbuf.msg_cbytes = msq->q_cbytes; tbuf.msg_qnum = msq->q_qnum; tbuf.msg_qbytes = msq->q_qbytes; tbuf.msg_lspid = msq->q_lspid; tbuf.msg_lrpid = msq->q_lrpid; rcu_read_unlock(); if (copy_msqid_to_user(buf, &tbuf, version)) return -EFAULT; return success_return; } default: return -EINVAL; } return err; out_unlock: rcu_read_unlock(); return err; }

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Pierre Peiffer27551.98%213.33%
Linus Torvalds (pre-git)11521.74%426.67%
Davidlohr Bueso A8015.12%320.00%
Stephen D. Smalley275.10%16.67%
Nadia Derbey152.84%16.67%
Steve Grubb71.32%16.67%
Linda Knippers50.95%16.67%
Kirill Korotaev30.57%16.67%
Serge E. Hallyn20.38%16.67%
Total529100.00%15100.00%

SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf) { int version; struct ipc_namespace *ns; if (msqid < 0 || cmd < 0) return -EINVAL; version = ipc_parse_version(&cmd); ns = current->nsproxy->ipc_ns; switch (cmd) { case IPC_INFO: case MSG_INFO: case MSG_STAT: /* msqid is an index rather than a msg queue id */ case IPC_STAT: return msgctl_nolock(ns, msqid, cmd, version, buf); case IPC_SET: case IPC_RMID: return msgctl_down(ns, msqid, cmd, buf, version); default: return -EINVAL; } }
static int testmsg(struct msg_msg *msg, long type, int mode) { switch (mode) { case SEARCH_ANY: case SEARCH_NUMBER: return 1; case SEARCH_LESSEQUAL: if (msg->m_type <= type) return 1; break; case SEARCH_EQUAL: if (msg->m_type == type) return 1; break; case SEARCH_NOTEQUAL: if (msg->m_type != type) return 1; break; } return 0; }

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Linus Torvalds (pre-git)7796.25%375.00%
Peter Hurley33.75%125.00%
Total80100.00%4100.00%


static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg, struct wake_q_head *wake_q) { struct msg_receiver *msr, *t; list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) { if (testmsg(msg, msr->r_msgtype, msr->r_mode) && !security_msg_queue_msgrcv(msq, msg, msr->r_tsk, msr->r_msgtype, msr->r_mode)) { list_del(&msr->r_list); if (msr->r_maxsize < msg->m_ts) { wake_q_add(wake_q, msr->r_tsk); WRITE_ONCE(msr->r_msg, ERR_PTR(-E2BIG)); } else { msq->q_lrpid = task_pid_vnr(msr->r_tsk); msq->q_rtime = get_seconds(); wake_q_add(wake_q, msr->r_tsk); WRITE_ONCE(msr->r_msg, msg); return 1; } } } return 0; }

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Linus Torvalds (pre-git)9557.23%325.00%
Stephen D. Smalley2012.05%18.33%
Sebastian Andrzej Siewior1911.45%18.33%
Manfred Spraul148.43%18.33%
Nikola Pajkovsky106.02%18.33%
Pavel Emelyanov31.81%18.33%
Andi Kleen21.20%18.33%
Stephen Rothwell10.60%18.33%
Dave Jones10.60%18.33%
Linus Torvalds10.60%18.33%
Total166100.00%12100.00%


long do_msgsnd(int msqid, long mtype, void __user *mtext, size_t msgsz, int msgflg) { struct msg_queue *msq; struct msg_msg *msg; int err; struct ipc_namespace *ns; DEFINE_WAKE_Q(wake_q); ns = current->nsproxy->ipc_ns; if (msgsz > ns->msg_ctlmax || (long) msgsz < 0 || msqid < 0) return -EINVAL; if (mtype < 1) return -EINVAL; msg = load_msg(mtext, msgsz); if (IS_ERR(msg)) return PTR_ERR(msg); msg->m_type = mtype; msg->m_ts = msgsz; rcu_read_lock(); msq = msq_obtain_object_check(ns, msqid); if (IS_ERR(msq)) { err = PTR_ERR(msq); goto out_unlock1; } ipc_lock_object(&msq->q_perm); for (;;) { struct msg_sender s; err = -EACCES; if (ipcperms(ns, &msq->q_perm, S_IWUGO)) goto out_unlock0; /* raced with RMID? */ if (!ipc_valid_object(&msq->q_perm)) { err = -EIDRM; goto out_unlock0; } err = security_msg_queue_msgsnd(msq, msg, msgflg); if (err) goto out_unlock0; if (msg_fits_inqueue(msq, msgsz)) break; /* queue full, wait: */ if (msgflg & IPC_NOWAIT) { err = -EAGAIN; goto out_unlock0; } /* enqueue the sender and prepare to block */ ss_add(msq, &s, msgsz); if (!ipc_rcu_getref(&msq->q_perm)) { err = -EIDRM; goto out_unlock0; } ipc_unlock_object(&msq->q_perm); rcu_read_unlock(); schedule(); rcu_read_lock(); ipc_lock_object(&msq->q_perm); ipc_rcu_putref(&msq->q_perm, msg_rcu_free); /* raced with RMID? */ if (!ipc_valid_object(&msq->q_perm)) { err = -EIDRM; goto out_unlock0; } ss_del(&s); if (signal_pending(current)) { err = -ERESTARTNOHAND; goto out_unlock0; } } msq->q_lspid = task_tgid_vnr(current); msq->q_stime = get_seconds(); if (!pipelined_send(msq, msg, &wake_q)) { /* no one is waiting for this message, enqueue it */ list_add_tail(&msg->m_list, &msq->q_messages); msq->q_cbytes += msgsz; msq->q_qnum++; atomic_add(msgsz, &ns->msg_bytes); atomic_inc(&ns->msg_hdrs); } err = 0; msg = NULL; out_unlock0: ipc_unlock_object(&msq->q_perm); wake_up_q(&wake_q); out_unlock1: rcu_read_unlock(); if (msg != NULL) free_msg(msg); return err; }

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Linus Torvalds (pre-git)27355.94%824.24%
Davidlohr Bueso A5411.07%515.15%
Manfred Spraul5010.25%39.09%
Kirill Korotaev214.30%26.06%
Stephen D. Smalley173.48%13.03%
Sebastian Andrzej Siewior132.66%13.03%
Rik Van Riel122.46%13.03%
Rafael Aquini112.25%13.03%
Linus Torvalds112.25%13.03%
Nadia Derbey71.43%13.03%
Suzuki K. Poulose61.23%13.03%
Pavel Emelyanov30.61%13.03%
Serge E. Hallyn20.41%13.03%
Andi Kleen20.41%13.03%
Andrew Morton20.41%13.03%
Waiman Long10.20%13.03%
Al Viro10.20%13.03%
Lucas De Marchi10.20%13.03%
Fabian Frederick10.20%13.03%
Total488100.00%33100.00%

SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, int, msgflg) { long mtype; if (get_user(mtype, &msgp->mtype)) return -EFAULT; return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg); }
static inline int convert_mode(long *msgtyp, int msgflg) { if (msgflg & MSG_COPY) return SEARCH_NUMBER; /* * find message of correct type. * msgtyp = 0 => get first. * msgtyp > 0 => get first message of matching type. * msgtyp < 0 => get message with least type must be < abs(msgtype). */ if (*msgtyp == 0) return SEARCH_ANY; if (*msgtyp < 0) { if (*msgtyp == LONG_MIN) /* -LONG_MIN is undefined */ *msgtyp = LONG_MAX; else *msgtyp = -*msgtyp; return SEARCH_LESSEQUAL; } if (msgflg & MSG_EXCEPT) return SEARCH_NOTEQUAL; return SEARCH_EQUAL; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)5367.09%228.57%
Jiri Slaby1417.72%114.29%
Peter Hurley911.39%114.29%
Stephen Rothwell11.27%114.29%
Ingo Molnar11.27%114.29%
Dave Jones11.27%114.29%
Total79100.00%7100.00%


static long do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz) { struct msgbuf __user *msgp = dest; size_t msgsz; if (put_user(msg->m_type, &msgp->mtype)) return -EFAULT; msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz; if (store_msg(msgp->mtext, msg, msgsz)) return -EFAULT; return msgsz; }

Contributors

PersonTokensPropCommitsCommitProp
Stanislav Kinsbursky84100.00%1100.00%
Total84100.00%1100.00%

#ifdef CONFIG_CHECKPOINT_RESTORE /* * This function creates new kernel message structure, large enough to store * bufsz message bytes. */
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz) { struct msg_msg *copy; /* * Create dummy message to copy real message to. */ copy = load_msg(buf, bufsz); if (!IS_ERR(copy)) copy->m_ts = bufsz; return copy; }

Contributors

PersonTokensPropCommitsCommitProp
Stanislav Kinsbursky49100.00%1100.00%
Total49100.00%1100.00%


static inline void free_copy(struct msg_msg *copy) { if (copy) free_msg(copy); }

Contributors

PersonTokensPropCommitsCommitProp
Stanislav Kinsbursky21100.00%2100.00%
Total21100.00%2100.00%

#else
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz) { return ERR_PTR(-ENOSYS); }

Contributors

PersonTokensPropCommitsCommitProp
Stanislav Kinsbursky24100.00%1100.00%
Total24100.00%1100.00%


static inline void free_copy(struct msg_msg *copy) { }

Contributors

PersonTokensPropCommitsCommitProp
Stanislav Kinsbursky11100.00%1100.00%
Total11100.00%1100.00%

#endif
static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode) { struct msg_msg *msg, *found = NULL; long count = 0; list_for_each_entry(msg, &msq->q_messages, m_list) { if (testmsg(msg, *msgtyp, mode) && !security_msg_queue_msgrcv(msq, msg, current, *msgtyp, mode)) { if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) { *msgtyp = msg->m_type - 1; found = msg; } else if (mode == SEARCH_NUMBER) { if (*msgtyp == count) return msg; } else return msg; count++; } } return found ?: ERR_PTR(-EAGAIN); }

Contributors

PersonTokensPropCommitsCommitProp
Peter Hurley12591.24%150.00%
Svenning Sörensen128.76%150.00%
Total137100.00%2100.00%


long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgflg, long (*msg_handler)(void __user *, struct msg_msg *, size_t)) { int mode; struct msg_queue *msq; struct ipc_namespace *ns; struct msg_msg *msg, *copy = NULL; DEFINE_WAKE_Q(wake_q); ns = current->nsproxy->ipc_ns; if (msqid < 0 || (long) bufsz < 0) return -EINVAL; if (msgflg & MSG_COPY) { if ((msgflg & MSG_EXCEPT) || !(msgflg & IPC_NOWAIT)) return -EINVAL; copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax)); if (IS_ERR(copy)) return PTR_ERR(copy); } mode = convert_mode(&msgtyp, msgflg); rcu_read_lock(); msq = msq_obtain_object_check(ns, msqid); if (IS_ERR(msq)) { rcu_read_unlock(); free_copy(copy); return PTR_ERR(msq); } for (;;) { struct msg_receiver msr_d; msg = ERR_PTR(-EACCES); if (ipcperms(ns, &msq->q_perm, S_IRUGO)) goto out_unlock1; ipc_lock_object(&msq->q_perm); /* raced with RMID? */ if (!ipc_valid_object(&msq->q_perm)) { msg = ERR_PTR(-EIDRM); goto out_unlock0; } msg = find_msg(msq, &msgtyp, mode); if (!IS_ERR(msg)) { /* * Found a suitable message. * Unlink it from the queue. */ if ((bufsz < msg->m_ts) && !(msgflg & MSG_NOERROR)) { msg = ERR_PTR(-E2BIG); goto out_unlock0; } /* * If we are copying, then do not unlink message and do * not update queue parameters. */ if (msgflg & MSG_COPY) { msg = copy_msg(msg, copy); goto out_unlock0; } list_del(&msg->m_list); msq->q_qnum--; msq->q_rtime = get_seconds(); msq->q_lrpid = task_tgid_vnr(current); msq->q_cbytes -= msg->m_ts; atomic_sub(msg->m_ts, &ns->msg_bytes); atomic_dec(&ns->msg_hdrs); ss_wakeup(msq, &wake_q, false); goto out_unlock0; } /* No message waiting. Wait for a message */ if (msgflg & IPC_NOWAIT) { msg = ERR_PTR(-ENOMSG); goto out_unlock0; } list_add_tail(&msr_d.r_list, &msq->q_receivers); msr_d.r_tsk = current; msr_d.r_msgtype = msgtyp; msr_d.r_mode = mode; if (msgflg & MSG_NOERROR) msr_d.r_maxsize = INT_MAX; else msr_d.r_maxsize = bufsz; msr_d.r_msg = ERR_PTR(-EAGAIN); __set_current_state(TASK_INTERRUPTIBLE); ipc_unlock_object(&msq->q_perm); rcu_read_unlock(); schedule(); /* * Lockless receive, part 1: * We don't hold a reference to the queue and getting a * reference would defeat the idea of a lockless operation, * thus the code relies on rcu to guarantee the existence of * msq: * Prior to destruction, expunge_all(-EIRDM) changes r_msg. * Thus if r_msg is -EAGAIN, then the queue not yet destroyed. */ rcu_read_lock(); /* * Lockless receive, part 2: * The work in pipelined_send() and expunge_all(): * - Set pointer to message * - Queue the receiver task for later wakeup * - Wake up the process after the lock is dropped. * * Should the process wake up before this wakeup (due to a * signal) it will either see the message and continue ... */ msg = READ_ONCE(msr_d.r_msg); if (msg != ERR_PTR(-EAGAIN)) goto out_unlock1; /* * ... or see -EAGAIN, acquire the lock to check the message * again. */ ipc_lock_object(&msq->q_perm); msg = msr_d.r_msg; if (msg != ERR_PTR(-EAGAIN)) goto out_unlock0; list_del(&msr_d.r_list); if (signal_pending(current)) { msg = ERR_PTR(-ERESTARTNOHAND); goto out_unlock0; } ipc_unlock_object(&msq->q_perm); } out_unlock0: ipc_unlock_object(&msq->q_perm); wake_up_q(&wake_q); out_unlock1: rcu_read_unlock(); if (IS_ERR(msg)) { free_copy(copy); return PTR_ERR(msg); } bufsz = msg_handler(buf, msg, bufsz); free_msg(msg); return bufsz; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)26940.88%820.51%
Davidlohr Bueso A16024.32%717.95%
Stanislav Kinsbursky7611.55%410.26%
Manfred Spraul548.21%12.56%
Peter Hurley294.41%37.69%
Michael Kerrisk192.89%12.56%
Kirill Korotaev101.52%25.13%
Stephen D. Smalley71.06%12.56%
Sebastian Andrzej Siewior60.91%12.56%
Linus Torvalds50.76%12.56%
Nadia Derbey50.76%12.56%
Rafael Aquini50.76%12.56%
Pavel Emelyanov30.46%12.56%
Andi Kleen20.30%12.56%
Suzuki K. Poulose20.30%12.56%
Serge E. Hallyn20.30%12.56%
Andrew Morton10.15%12.56%
Al Viro10.15%12.56%
Ingo Molnar10.15%12.56%
Waiman Long10.15%12.56%
Total658100.00%39100.00%

SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, long, msgtyp, int, msgflg) { return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill); }
void msg_init_ns(struct ipc_namespace *ns) { ns->msg_ctlmax = MSGMAX; ns->msg_ctlmnb = MSGMNB; ns->msg_ctlmni = MSGMNI; atomic_set(&ns->msg_bytes, 0); atomic_set(&ns->msg_hdrs, 0); ipc_init_ids(&ns->ids[IPC_MSG_IDS]); }

Contributors

PersonTokensPropCommitsCommitProp
Davidlohr Bueso A4474.58%225.00%
Manfred Spraul1016.95%225.00%
Linus Torvalds (pre-git)46.78%337.50%
Stanislav Kinsbursky11.69%112.50%
Total59100.00%8100.00%

#ifdef CONFIG_IPC_NS
void msg_exit_ns(struct ipc_namespace *ns) { free_ipcs(ns, &msg_ids(ns), freeque); idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr); }

Contributors

PersonTokensPropCommitsCommitProp
Davidlohr Bueso A3083.33%150.00%
Suzuki K. Poulose616.67%150.00%
Total36100.00%2100.00%

#endif #ifdef CONFIG_PROC_FS
static int sysvipc_msg_proc_show(struct seq_file *s, void *it) { struct user_namespace *user_ns = seq_user_ns(s); struct kern_ipc_perm *ipcp = it; struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm); seq_printf(s, "%10d %10d %4o %10lu %10lu %5u %5u %5u %5u %5u %5u %10lu %10lu %10lu\n", msq->q_perm.key, msq->q_perm.id, msq->q_perm.mode, msq->q_cbytes, msq->q_qnum, msq->q_lspid, msq->q_lrpid, from_kuid_munged(user_ns, msq->q_perm.uid), from_kgid_munged(user_ns, msq->q_perm.gid), from_kuid_munged(user_ns, msq->q_perm.cuid), from_kgid_munged(user_ns, msq->q_perm.cgid), msq->q_stime, msq->q_rtime, msq->q_ctime); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)8759.18%444.44%
Eric W. Biedermann3020.41%111.11%
Kees Cook1610.88%111.11%
Mike Waychison85.44%111.11%
Nadia Derbey32.04%111.11%
Joe Perches32.04%111.11%
Total147100.00%9100.00%

#endif
void __init msg_init(void) { msg_init_ns(&init_ipc_ns); ipc_init_proc_interface("sysvipc/msg", " key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n", IPC_MSG_IDS, sysvipc_msg_proc_show); }

Contributors

PersonTokensPropCommitsCommitProp
Davidlohr Bueso A25100.00%1100.00%
Total25100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)176537.83%1916.24%
Davidlohr Bueso A92119.74%2218.80%
Pierre Peiffer47410.16%65.13%
Stanislav Kinsbursky2745.87%54.27%
Peter Hurley1703.64%43.42%
Nadia Derbey1613.45%65.13%
Manfred Spraul1573.37%65.13%
Stephen D. Smalley1052.25%21.71%
Kirill Korotaev821.76%21.71%
Sebastian Andrzej Siewior661.41%10.85%
Linus Torvalds521.11%21.71%
Suzuki K. Poulose511.09%10.85%
Eric W. Biedermann450.96%10.85%
Nikola Pajkovsky420.90%10.85%
Kees Cook360.77%32.56%
Heiko Carstens320.69%10.85%
Greg Kroah-Hartman230.49%32.56%
Ingo Molnar200.43%32.56%
Michael Kerrisk190.41%10.85%
Rafael Aquini160.34%10.85%
Mathias Krause140.30%10.85%
Jiri Slaby140.30%10.85%
Pavel Emelyanov120.26%21.71%
Svenning Sörensen120.26%10.85%
Rik Van Riel120.26%10.85%
Andrew Morton110.24%21.71%
Mike Waychison110.24%10.85%
Andi Kleen80.17%10.85%
Serge E. Hallyn80.17%10.85%
Steve Grubb70.15%10.85%
Alexey Dobriyan60.13%10.85%
Al Viro50.11%10.85%
Linda Knippers50.11%10.85%
Waiman Long40.09%10.85%
Arnd Bergmann30.06%10.85%
Randy Dunlap30.06%10.85%
Joe Perches30.06%10.85%
David Woodhouse30.06%10.85%
Arnaldo Carvalho de Melo30.06%10.85%
Felipe Contreras30.06%10.85%
Dave Jones20.04%10.85%
Stephen Rothwell20.04%10.85%
Lucas De Marchi10.02%10.85%
Fabian Frederick10.02%10.85%
Paul McQuade10.02%10.85%
Total4665100.00%117100.00%
Directory: ipc
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