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![Jules Irenge](/assets/img/avatar_default.png)
Sparse reports a warning at freeque() warning: context imbalance in freeque() - unexpected unlock The root cause is the missing annotation at freeque() Add the missing __releases(RCU) annotation Add the missing __releases(&msq->q_perm) annotation Signed-off-by: Jules Irenge <jbi.octave@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Lu Shuaibing <shuaibinglu@126.com> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Link: http://lkml.kernel.org/r/20200403160505.2832-2-jbi.octave@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1354 lines
32 KiB
C
1354 lines
32 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* linux/ipc/msg.c
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* Copyright (C) 1992 Krishna Balasubramanian
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*
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* Removed all the remaining kerneld mess
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* Catch the -EFAULT stuff properly
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* Use GFP_KERNEL for messages as in 1.2
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* Fixed up the unchecked user space derefs
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* Copyright (C) 1998 Alan Cox & Andi Kleen
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*
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* /proc/sysvipc/msg support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
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*
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* mostly rewritten, threaded and wake-one semantics added
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* MSGMAX limit removed, sysctl's added
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* (c) 1999 Manfred Spraul <manfred@colorfullife.com>
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*
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* support for audit of ipc object properties and permission changes
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* Dustin Kirkland <dustin.kirkland@us.ibm.com>
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*
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* namespaces support
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* OpenVZ, SWsoft Inc.
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* Pavel Emelianov <xemul@openvz.org>
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*/
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#include <linux/capability.h>
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#include <linux/msg.h>
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#include <linux/spinlock.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/proc_fs.h>
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#include <linux/list.h>
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#include <linux/security.h>
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#include <linux/sched/wake_q.h>
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#include <linux/syscalls.h>
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#include <linux/audit.h>
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#include <linux/seq_file.h>
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#include <linux/rwsem.h>
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#include <linux/nsproxy.h>
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#include <linux/ipc_namespace.h>
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#include <linux/rhashtable.h>
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#include <asm/current.h>
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#include <linux/uaccess.h>
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#include "util.h"
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/* one msq_queue structure for each present queue on the system */
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struct msg_queue {
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struct kern_ipc_perm q_perm;
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time64_t q_stime; /* last msgsnd time */
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time64_t q_rtime; /* last msgrcv time */
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time64_t q_ctime; /* last change time */
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unsigned long q_cbytes; /* current number of bytes on queue */
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unsigned long q_qnum; /* number of messages in queue */
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unsigned long q_qbytes; /* max number of bytes on queue */
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struct pid *q_lspid; /* pid of last msgsnd */
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struct pid *q_lrpid; /* last receive pid */
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struct list_head q_messages;
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struct list_head q_receivers;
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struct list_head q_senders;
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} __randomize_layout;
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/*
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* MSG_BARRIER Locking:
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*
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* Similar to the optimization used in ipc/mqueue.c, one syscall return path
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* does not acquire any locks when it sees that a message exists in
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* msg_receiver.r_msg. Therefore r_msg is set using smp_store_release()
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* and accessed using READ_ONCE()+smp_acquire__after_ctrl_dep(). In addition,
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* wake_q_add_safe() is used. See ipc/mqueue.c for more details
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*/
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/* one msg_receiver structure for each sleeping receiver */
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struct msg_receiver {
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struct list_head r_list;
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struct task_struct *r_tsk;
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int r_mode;
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long r_msgtype;
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long r_maxsize;
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struct msg_msg *r_msg;
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};
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/* one msg_sender for each sleeping sender */
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struct msg_sender {
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struct list_head list;
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struct task_struct *tsk;
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size_t msgsz;
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};
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#define SEARCH_ANY 1
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#define SEARCH_EQUAL 2
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#define SEARCH_NOTEQUAL 3
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#define SEARCH_LESSEQUAL 4
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#define SEARCH_NUMBER 5
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#define msg_ids(ns) ((ns)->ids[IPC_MSG_IDS])
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static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, int id)
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{
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struct kern_ipc_perm *ipcp = ipc_obtain_object_idr(&msg_ids(ns), id);
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if (IS_ERR(ipcp))
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return ERR_CAST(ipcp);
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return container_of(ipcp, struct msg_queue, q_perm);
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}
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static inline struct msg_queue *msq_obtain_object_check(struct ipc_namespace *ns,
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int id)
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{
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struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&msg_ids(ns), id);
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if (IS_ERR(ipcp))
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return ERR_CAST(ipcp);
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return container_of(ipcp, struct msg_queue, q_perm);
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}
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static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
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{
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ipc_rmid(&msg_ids(ns), &s->q_perm);
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}
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static void msg_rcu_free(struct rcu_head *head)
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{
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struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
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struct msg_queue *msq = container_of(p, struct msg_queue, q_perm);
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security_msg_queue_free(&msq->q_perm);
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kvfree(msq);
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}
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/**
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* newque - Create a new msg queue
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* @ns: namespace
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* @params: ptr to the structure that contains the key and msgflg
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*
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* Called with msg_ids.rwsem held (writer)
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*/
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static int newque(struct ipc_namespace *ns, struct ipc_params *params)
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{
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struct msg_queue *msq;
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int retval;
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key_t key = params->key;
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int msgflg = params->flg;
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msq = kvmalloc(sizeof(*msq), GFP_KERNEL);
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if (unlikely(!msq))
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return -ENOMEM;
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msq->q_perm.mode = msgflg & S_IRWXUGO;
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msq->q_perm.key = key;
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msq->q_perm.security = NULL;
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retval = security_msg_queue_alloc(&msq->q_perm);
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if (retval) {
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kvfree(msq);
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return retval;
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}
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msq->q_stime = msq->q_rtime = 0;
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msq->q_ctime = ktime_get_real_seconds();
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msq->q_cbytes = msq->q_qnum = 0;
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msq->q_qbytes = ns->msg_ctlmnb;
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msq->q_lspid = msq->q_lrpid = NULL;
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INIT_LIST_HEAD(&msq->q_messages);
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INIT_LIST_HEAD(&msq->q_receivers);
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INIT_LIST_HEAD(&msq->q_senders);
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/* ipc_addid() locks msq upon success. */
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retval = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
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if (retval < 0) {
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ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
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return retval;
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}
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ipc_unlock_object(&msq->q_perm);
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rcu_read_unlock();
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return msq->q_perm.id;
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}
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static inline bool msg_fits_inqueue(struct msg_queue *msq, size_t msgsz)
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{
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return msgsz + msq->q_cbytes <= msq->q_qbytes &&
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1 + msq->q_qnum <= msq->q_qbytes;
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}
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static inline void ss_add(struct msg_queue *msq,
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struct msg_sender *mss, size_t msgsz)
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{
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mss->tsk = current;
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mss->msgsz = msgsz;
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/*
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* No memory barrier required: we did ipc_lock_object(),
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* and the waker obtains that lock before calling wake_q_add().
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*/
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__set_current_state(TASK_INTERRUPTIBLE);
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list_add_tail(&mss->list, &msq->q_senders);
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}
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static inline void ss_del(struct msg_sender *mss)
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{
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if (mss->list.next)
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list_del(&mss->list);
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}
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static void ss_wakeup(struct msg_queue *msq,
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struct wake_q_head *wake_q, bool kill)
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{
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struct msg_sender *mss, *t;
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struct task_struct *stop_tsk = NULL;
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struct list_head *h = &msq->q_senders;
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list_for_each_entry_safe(mss, t, h, list) {
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if (kill)
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mss->list.next = NULL;
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/*
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* Stop at the first task we don't wakeup,
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* we've already iterated the original
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* sender queue.
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*/
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else if (stop_tsk == mss->tsk)
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break;
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/*
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* We are not in an EIDRM scenario here, therefore
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* verify that we really need to wakeup the task.
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* To maintain current semantics and wakeup order,
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* move the sender to the tail on behalf of the
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* blocked task.
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*/
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else if (!msg_fits_inqueue(msq, mss->msgsz)) {
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if (!stop_tsk)
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stop_tsk = mss->tsk;
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list_move_tail(&mss->list, &msq->q_senders);
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continue;
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}
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wake_q_add(wake_q, mss->tsk);
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}
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}
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static void expunge_all(struct msg_queue *msq, int res,
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struct wake_q_head *wake_q)
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{
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struct msg_receiver *msr, *t;
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list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
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get_task_struct(msr->r_tsk);
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/* see MSG_BARRIER for purpose/pairing */
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smp_store_release(&msr->r_msg, ERR_PTR(res));
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wake_q_add_safe(wake_q, msr->r_tsk);
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}
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}
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/*
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* freeque() wakes up waiters on the sender and receiver waiting queue,
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* removes the message queue from message queue ID IDR, and cleans up all the
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* messages associated with this queue.
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*
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* msg_ids.rwsem (writer) and the spinlock for this message queue are held
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* before freeque() is called. msg_ids.rwsem remains locked on exit.
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*/
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static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
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__releases(RCU)
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__releases(&msq->q_perm)
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{
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struct msg_msg *msg, *t;
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struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
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DEFINE_WAKE_Q(wake_q);
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expunge_all(msq, -EIDRM, &wake_q);
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ss_wakeup(msq, &wake_q, true);
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msg_rmid(ns, msq);
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ipc_unlock_object(&msq->q_perm);
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wake_up_q(&wake_q);
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rcu_read_unlock();
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list_for_each_entry_safe(msg, t, &msq->q_messages, m_list) {
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atomic_dec(&ns->msg_hdrs);
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free_msg(msg);
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}
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atomic_sub(msq->q_cbytes, &ns->msg_bytes);
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ipc_update_pid(&msq->q_lspid, NULL);
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ipc_update_pid(&msq->q_lrpid, NULL);
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ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
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}
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long ksys_msgget(key_t key, int msgflg)
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{
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struct ipc_namespace *ns;
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static const struct ipc_ops msg_ops = {
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.getnew = newque,
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.associate = security_msg_queue_associate,
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};
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struct ipc_params msg_params;
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ns = current->nsproxy->ipc_ns;
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msg_params.key = key;
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msg_params.flg = msgflg;
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return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params);
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}
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SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg)
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{
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return ksys_msgget(key, msgflg);
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}
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static inline unsigned long
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copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version)
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{
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switch (version) {
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case IPC_64:
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return copy_to_user(buf, in, sizeof(*in));
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case IPC_OLD:
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{
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struct msqid_ds out;
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memset(&out, 0, sizeof(out));
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ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm);
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out.msg_stime = in->msg_stime;
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out.msg_rtime = in->msg_rtime;
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out.msg_ctime = in->msg_ctime;
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if (in->msg_cbytes > USHRT_MAX)
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out.msg_cbytes = USHRT_MAX;
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else
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out.msg_cbytes = in->msg_cbytes;
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out.msg_lcbytes = in->msg_cbytes;
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if (in->msg_qnum > USHRT_MAX)
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out.msg_qnum = USHRT_MAX;
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else
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out.msg_qnum = in->msg_qnum;
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if (in->msg_qbytes > USHRT_MAX)
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out.msg_qbytes = USHRT_MAX;
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else
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out.msg_qbytes = in->msg_qbytes;
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out.msg_lqbytes = in->msg_qbytes;
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out.msg_lspid = in->msg_lspid;
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out.msg_lrpid = in->msg_lrpid;
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return copy_to_user(buf, &out, sizeof(out));
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}
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default:
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return -EINVAL;
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}
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}
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static inline unsigned long
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copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version)
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{
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switch (version) {
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case IPC_64:
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if (copy_from_user(out, buf, sizeof(*out)))
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return -EFAULT;
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return 0;
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case IPC_OLD:
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{
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struct msqid_ds tbuf_old;
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if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
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return -EFAULT;
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out->msg_perm.uid = tbuf_old.msg_perm.uid;
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out->msg_perm.gid = tbuf_old.msg_perm.gid;
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out->msg_perm.mode = tbuf_old.msg_perm.mode;
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if (tbuf_old.msg_qbytes == 0)
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out->msg_qbytes = tbuf_old.msg_lqbytes;
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else
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out->msg_qbytes = tbuf_old.msg_qbytes;
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return 0;
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}
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default:
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return -EINVAL;
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}
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}
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/*
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* This function handles some msgctl commands which require the rwsem
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* to be held in write mode.
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* NOTE: no locks must be held, the rwsem is taken inside this function.
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*/
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static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
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struct ipc64_perm *perm, int msg_qbytes)
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{
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struct kern_ipc_perm *ipcp;
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struct msg_queue *msq;
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int err;
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down_write(&msg_ids(ns).rwsem);
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rcu_read_lock();
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ipcp = ipcctl_obtain_check(ns, &msg_ids(ns), msqid, cmd,
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perm, msg_qbytes);
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if (IS_ERR(ipcp)) {
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err = PTR_ERR(ipcp);
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goto out_unlock1;
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}
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msq = container_of(ipcp, struct msg_queue, q_perm);
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err = security_msg_queue_msgctl(&msq->q_perm, cmd);
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if (err)
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goto out_unlock1;
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switch (cmd) {
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case IPC_RMID:
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ipc_lock_object(&msq->q_perm);
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/* freeque unlocks the ipc object and rcu */
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freeque(ns, ipcp);
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goto out_up;
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case IPC_SET:
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{
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DEFINE_WAKE_Q(wake_q);
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|
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if (msg_qbytes > ns->msg_ctlmnb &&
|
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!capable(CAP_SYS_RESOURCE)) {
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err = -EPERM;
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goto out_unlock1;
|
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}
|
|
|
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ipc_lock_object(&msq->q_perm);
|
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err = ipc_update_perm(perm, ipcp);
|
|
if (err)
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goto out_unlock0;
|
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|
|
msq->q_qbytes = msg_qbytes;
|
|
|
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msq->q_ctime = ktime_get_real_seconds();
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/*
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* Sleeping receivers might be excluded by
|
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* stricter permissions.
|
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*/
|
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expunge_all(msq, -EAGAIN, &wake_q);
|
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/*
|
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* Sleeping senders might be able to send
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* due to a larger queue size.
|
|
*/
|
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ss_wakeup(msq, &wake_q, false);
|
|
ipc_unlock_object(&msq->q_perm);
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wake_up_q(&wake_q);
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|
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goto out_unlock1;
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|
}
|
|
default:
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err = -EINVAL;
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goto out_unlock1;
|
|
}
|
|
|
|
out_unlock0:
|
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ipc_unlock_object(&msq->q_perm);
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|
out_unlock1:
|
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rcu_read_unlock();
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|
out_up:
|
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up_write(&msg_ids(ns).rwsem);
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return err;
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}
|
|
|
|
static int msgctl_info(struct ipc_namespace *ns, int msqid,
|
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int cmd, struct msginfo *msginfo)
|
|
{
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|
int err;
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int max_idx;
|
|
|
|
/*
|
|
* 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_idx = ipc_get_maxidx(&msg_ids(ns));
|
|
up_read(&msg_ids(ns).rwsem);
|
|
return (max_idx < 0) ? 0 : max_idx;
|
|
}
|
|
|
|
static int msgctl_stat(struct ipc_namespace *ns, int msqid,
|
|
int cmd, struct msqid64_ds *p)
|
|
{
|
|
struct msg_queue *msq;
|
|
int err;
|
|
|
|
memset(p, 0, sizeof(*p));
|
|
|
|
rcu_read_lock();
|
|
if (cmd == MSG_STAT || cmd == MSG_STAT_ANY) {
|
|
msq = msq_obtain_object(ns, msqid);
|
|
if (IS_ERR(msq)) {
|
|
err = PTR_ERR(msq);
|
|
goto out_unlock;
|
|
}
|
|
} else { /* IPC_STAT */
|
|
msq = msq_obtain_object_check(ns, msqid);
|
|
if (IS_ERR(msq)) {
|
|
err = PTR_ERR(msq);
|
|
goto out_unlock;
|
|
}
|
|
}
|
|
|
|
/* see comment for SHM_STAT_ANY */
|
|
if (cmd == MSG_STAT_ANY)
|
|
audit_ipc_obj(&msq->q_perm);
|
|
else {
|
|
err = -EACCES;
|
|
if (ipcperms(ns, &msq->q_perm, S_IRUGO))
|
|
goto out_unlock;
|
|
}
|
|
|
|
err = security_msg_queue_msgctl(&msq->q_perm, cmd);
|
|
if (err)
|
|
goto out_unlock;
|
|
|
|
ipc_lock_object(&msq->q_perm);
|
|
|
|
if (!ipc_valid_object(&msq->q_perm)) {
|
|
ipc_unlock_object(&msq->q_perm);
|
|
err = -EIDRM;
|
|
goto out_unlock;
|
|
}
|
|
|
|
kernel_to_ipc64_perm(&msq->q_perm, &p->msg_perm);
|
|
p->msg_stime = msq->q_stime;
|
|
p->msg_rtime = msq->q_rtime;
|
|
p->msg_ctime = msq->q_ctime;
|
|
#ifndef CONFIG_64BIT
|
|
p->msg_stime_high = msq->q_stime >> 32;
|
|
p->msg_rtime_high = msq->q_rtime >> 32;
|
|
p->msg_ctime_high = msq->q_ctime >> 32;
|
|
#endif
|
|
p->msg_cbytes = msq->q_cbytes;
|
|
p->msg_qnum = msq->q_qnum;
|
|
p->msg_qbytes = msq->q_qbytes;
|
|
p->msg_lspid = pid_vnr(msq->q_lspid);
|
|
p->msg_lrpid = pid_vnr(msq->q_lrpid);
|
|
|
|
if (cmd == IPC_STAT) {
|
|
/*
|
|
* As defined in SUS:
|
|
* Return 0 on success
|
|
*/
|
|
err = 0;
|
|
} else {
|
|
/*
|
|
* MSG_STAT and MSG_STAT_ANY (both Linux specific)
|
|
* Return the full id, including the sequence number
|
|
*/
|
|
err = msq->q_perm.id;
|
|
}
|
|
|
|
ipc_unlock_object(&msq->q_perm);
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
return err;
|
|
}
|
|
|
|
static long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf, int version)
|
|
{
|
|
struct ipc_namespace *ns;
|
|
struct msqid64_ds msqid64;
|
|
int err;
|
|
|
|
if (msqid < 0 || cmd < 0)
|
|
return -EINVAL;
|
|
|
|
ns = current->nsproxy->ipc_ns;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case MSG_INFO: {
|
|
struct msginfo msginfo;
|
|
err = msgctl_info(ns, msqid, cmd, &msginfo);
|
|
if (err < 0)
|
|
return err;
|
|
if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
|
|
err = -EFAULT;
|
|
return err;
|
|
}
|
|
case MSG_STAT: /* msqid is an index rather than a msg queue id */
|
|
case MSG_STAT_ANY:
|
|
case IPC_STAT:
|
|
err = msgctl_stat(ns, msqid, cmd, &msqid64);
|
|
if (err < 0)
|
|
return err;
|
|
if (copy_msqid_to_user(buf, &msqid64, version))
|
|
err = -EFAULT;
|
|
return err;
|
|
case IPC_SET:
|
|
if (copy_msqid_from_user(&msqid64, buf, version))
|
|
return -EFAULT;
|
|
return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm,
|
|
msqid64.msg_qbytes);
|
|
case IPC_RMID:
|
|
return msgctl_down(ns, msqid, cmd, NULL, 0);
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
|
|
{
|
|
return ksys_msgctl(msqid, cmd, buf, IPC_64);
|
|
}
|
|
|
|
#ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
|
|
long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
|
|
{
|
|
int version = ipc_parse_version(&cmd);
|
|
|
|
return ksys_msgctl(msqid, cmd, buf, version);
|
|
}
|
|
|
|
SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
|
|
{
|
|
return ksys_old_msgctl(msqid, cmd, buf);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
|
|
struct compat_msqid_ds {
|
|
struct compat_ipc_perm msg_perm;
|
|
compat_uptr_t msg_first;
|
|
compat_uptr_t msg_last;
|
|
old_time32_t msg_stime;
|
|
old_time32_t msg_rtime;
|
|
old_time32_t msg_ctime;
|
|
compat_ulong_t msg_lcbytes;
|
|
compat_ulong_t msg_lqbytes;
|
|
unsigned short msg_cbytes;
|
|
unsigned short msg_qnum;
|
|
unsigned short msg_qbytes;
|
|
compat_ipc_pid_t msg_lspid;
|
|
compat_ipc_pid_t msg_lrpid;
|
|
};
|
|
|
|
static int copy_compat_msqid_from_user(struct msqid64_ds *out, void __user *buf,
|
|
int version)
|
|
{
|
|
memset(out, 0, sizeof(*out));
|
|
if (version == IPC_64) {
|
|
struct compat_msqid64_ds __user *p = buf;
|
|
if (get_compat_ipc64_perm(&out->msg_perm, &p->msg_perm))
|
|
return -EFAULT;
|
|
if (get_user(out->msg_qbytes, &p->msg_qbytes))
|
|
return -EFAULT;
|
|
} else {
|
|
struct compat_msqid_ds __user *p = buf;
|
|
if (get_compat_ipc_perm(&out->msg_perm, &p->msg_perm))
|
|
return -EFAULT;
|
|
if (get_user(out->msg_qbytes, &p->msg_qbytes))
|
|
return -EFAULT;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in,
|
|
int version)
|
|
{
|
|
if (version == IPC_64) {
|
|
struct compat_msqid64_ds v;
|
|
memset(&v, 0, sizeof(v));
|
|
to_compat_ipc64_perm(&v.msg_perm, &in->msg_perm);
|
|
v.msg_stime = lower_32_bits(in->msg_stime);
|
|
v.msg_stime_high = upper_32_bits(in->msg_stime);
|
|
v.msg_rtime = lower_32_bits(in->msg_rtime);
|
|
v.msg_rtime_high = upper_32_bits(in->msg_rtime);
|
|
v.msg_ctime = lower_32_bits(in->msg_ctime);
|
|
v.msg_ctime_high = upper_32_bits(in->msg_ctime);
|
|
v.msg_cbytes = in->msg_cbytes;
|
|
v.msg_qnum = in->msg_qnum;
|
|
v.msg_qbytes = in->msg_qbytes;
|
|
v.msg_lspid = in->msg_lspid;
|
|
v.msg_lrpid = in->msg_lrpid;
|
|
return copy_to_user(buf, &v, sizeof(v));
|
|
} else {
|
|
struct compat_msqid_ds v;
|
|
memset(&v, 0, sizeof(v));
|
|
to_compat_ipc_perm(&v.msg_perm, &in->msg_perm);
|
|
v.msg_stime = in->msg_stime;
|
|
v.msg_rtime = in->msg_rtime;
|
|
v.msg_ctime = in->msg_ctime;
|
|
v.msg_cbytes = in->msg_cbytes;
|
|
v.msg_qnum = in->msg_qnum;
|
|
v.msg_qbytes = in->msg_qbytes;
|
|
v.msg_lspid = in->msg_lspid;
|
|
v.msg_lrpid = in->msg_lrpid;
|
|
return copy_to_user(buf, &v, sizeof(v));
|
|
}
|
|
}
|
|
|
|
static long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr, int version)
|
|
{
|
|
struct ipc_namespace *ns;
|
|
int err;
|
|
struct msqid64_ds msqid64;
|
|
|
|
ns = current->nsproxy->ipc_ns;
|
|
|
|
if (msqid < 0 || cmd < 0)
|
|
return -EINVAL;
|
|
|
|
switch (cmd & (~IPC_64)) {
|
|
case IPC_INFO:
|
|
case MSG_INFO: {
|
|
struct msginfo msginfo;
|
|
err = msgctl_info(ns, msqid, cmd, &msginfo);
|
|
if (err < 0)
|
|
return err;
|
|
if (copy_to_user(uptr, &msginfo, sizeof(struct msginfo)))
|
|
err = -EFAULT;
|
|
return err;
|
|
}
|
|
case IPC_STAT:
|
|
case MSG_STAT:
|
|
case MSG_STAT_ANY:
|
|
err = msgctl_stat(ns, msqid, cmd, &msqid64);
|
|
if (err < 0)
|
|
return err;
|
|
if (copy_compat_msqid_to_user(uptr, &msqid64, version))
|
|
err = -EFAULT;
|
|
return err;
|
|
case IPC_SET:
|
|
if (copy_compat_msqid_from_user(&msqid64, uptr, version))
|
|
return -EFAULT;
|
|
return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm, msqid64.msg_qbytes);
|
|
case IPC_RMID:
|
|
return msgctl_down(ns, msqid, cmd, NULL, 0);
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr)
|
|
{
|
|
return compat_ksys_msgctl(msqid, cmd, uptr, IPC_64);
|
|
}
|
|
|
|
#ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
|
|
long compat_ksys_old_msgctl(int msqid, int cmd, void __user *uptr)
|
|
{
|
|
int version = compat_ipc_parse_version(&cmd);
|
|
|
|
return compat_ksys_msgctl(msqid, cmd, uptr, version);
|
|
}
|
|
|
|
COMPAT_SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, void __user *, uptr)
|
|
{
|
|
return compat_ksys_old_msgctl(msqid, cmd, uptr);
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
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;
|
|
}
|
|
|
|
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->q_perm, 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);
|
|
|
|
/* See expunge_all regarding memory barrier */
|
|
smp_store_release(&msr->r_msg, ERR_PTR(-E2BIG));
|
|
} else {
|
|
ipc_update_pid(&msq->q_lrpid, task_pid(msr->r_tsk));
|
|
msq->q_rtime = ktime_get_real_seconds();
|
|
|
|
wake_q_add(wake_q, msr->r_tsk);
|
|
|
|
/* See expunge_all regarding memory barrier */
|
|
smp_store_release(&msr->r_msg, msg);
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static 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->q_perm, 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;
|
|
}
|
|
|
|
}
|
|
|
|
ipc_update_pid(&msq->q_lspid, task_tgid(current));
|
|
msq->q_stime = ktime_get_real_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;
|
|
}
|
|
|
|
long ksys_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);
|
|
}
|
|
|
|
SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
|
|
int, msgflg)
|
|
{
|
|
return ksys_msgsnd(msqid, msgp, msgsz, msgflg);
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
|
|
struct compat_msgbuf {
|
|
compat_long_t mtype;
|
|
char mtext[1];
|
|
};
|
|
|
|
long compat_ksys_msgsnd(int msqid, compat_uptr_t msgp,
|
|
compat_ssize_t msgsz, int msgflg)
|
|
{
|
|
struct compat_msgbuf __user *up = compat_ptr(msgp);
|
|
compat_long_t mtype;
|
|
|
|
if (get_user(mtype, &up->mtype))
|
|
return -EFAULT;
|
|
return do_msgsnd(msqid, mtype, up->mtext, (ssize_t)msgsz, msgflg);
|
|
}
|
|
|
|
COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp,
|
|
compat_ssize_t, msgsz, int, msgflg)
|
|
{
|
|
return compat_ksys_msgsnd(msqid, msgp, msgsz, msgflg);
|
|
}
|
|
#endif
|
|
|
|
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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
#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;
|
|
}
|
|
|
|
static inline void free_copy(struct msg_msg *copy)
|
|
{
|
|
if (copy)
|
|
free_msg(copy);
|
|
}
|
|
#else
|
|
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
|
|
{
|
|
return ERR_PTR(-ENOSYS);
|
|
}
|
|
|
|
static inline void free_copy(struct msg_msg *copy)
|
|
{
|
|
}
|
|
#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->q_perm, 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);
|
|
}
|
|
|
|
static 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 = ktime_get_real_seconds();
|
|
ipc_update_pid(&msq->q_lrpid, task_tgid(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;
|
|
|
|
/* memory barrier not require due to ipc_lock_object() */
|
|
WRITE_ONCE(msr_d.r_msg, ERR_PTR(-EAGAIN));
|
|
|
|
/* memory barrier not required, we own ipc_lock_object() */
|
|
__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)) {
|
|
/* see MSG_BARRIER for purpose/pairing */
|
|
smp_acquire__after_ctrl_dep();
|
|
|
|
goto out_unlock1;
|
|
}
|
|
|
|
/*
|
|
* ... or see -EAGAIN, acquire the lock to check the message
|
|
* again.
|
|
*/
|
|
ipc_lock_object(&msq->q_perm);
|
|
|
|
msg = READ_ONCE(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;
|
|
}
|
|
|
|
long ksys_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);
|
|
}
|
|
|
|
SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
|
|
long, msgtyp, int, msgflg)
|
|
{
|
|
return ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
static long compat_do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
|
|
{
|
|
struct compat_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;
|
|
}
|
|
|
|
long compat_ksys_msgrcv(int msqid, compat_uptr_t msgp, compat_ssize_t msgsz,
|
|
compat_long_t msgtyp, int msgflg)
|
|
{
|
|
return do_msgrcv(msqid, compat_ptr(msgp), (ssize_t)msgsz, (long)msgtyp,
|
|
msgflg, compat_do_msg_fill);
|
|
}
|
|
|
|
COMPAT_SYSCALL_DEFINE5(msgrcv, int, msqid, compat_uptr_t, msgp,
|
|
compat_ssize_t, msgsz, compat_long_t, msgtyp,
|
|
int, msgflg)
|
|
{
|
|
return compat_ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
|
|
}
|
|
#endif
|
|
|
|
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]);
|
|
}
|
|
|
|
#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);
|
|
rhashtable_destroy(&ns->ids[IPC_MSG_IDS].key_ht);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
|
|
{
|
|
struct pid_namespace *pid_ns = ipc_seq_pid_ns(s);
|
|
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 %10llu %10llu %10llu\n",
|
|
msq->q_perm.key,
|
|
msq->q_perm.id,
|
|
msq->q_perm.mode,
|
|
msq->q_cbytes,
|
|
msq->q_qnum,
|
|
pid_nr_ns(msq->q_lspid, pid_ns),
|
|
pid_nr_ns(msq->q_lrpid, pid_ns),
|
|
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;
|
|
}
|
|
#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);
|
|
}
|