/* * 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/slab.h>#include <linux/msg.h>#include <linux/spinlock.h>#include <linux/init.h>#include <linux/proc_fs.h>#include <linux/list.h>#include <linux/security.h>#include <linux/sched.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 <asm/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 *volatile r_msg;}; /* one msg_sender for each sleeping sender */struct msg_sender { struct list_head list; struct task_struct *tsk;}; #define SEARCH_ANY 1#define SEARCH_EQUAL 2#define SEARCH_NOTEQUAL 3#define SEARCH_LESSEQUAL 4 #define msg_ids(ns) ((ns)->ids[IPC_MSG_IDS]) #define msg_unlock(msq) ipc_unlock(&(msq)->q_perm)#define msg_buildid(id, seq) ipc_buildid(id, seq) static void freeque(struct ipc_namespace *, struct kern_ipc_perm *);static int newque(struct ipc_namespace *, struct ipc_params *);#ifdef CONFIG_PROC_FSstatic int sysvipc_msg_proc_show(struct seq_file *s, void *it);#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_NSvoid msg_exit_ns(struct ipc_namespace *ns){ free_ipcs(ns, &msg_ids(ns), freeque);}#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);} /* * This routine is called in the paths where the rw_mutex is held to protect * access to the idr tree. */static inline struct msg_queue *msg_lock_check_down(struct ipc_namespace *ns, int id){ struct kern_ipc_perm *ipcp = ipc_lock_check_down(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm);} /* * msg_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */static inline struct msg_queue *msg_lock(struct ipc_namespace *ns, int id){ struct kern_ipc_perm *ipcp = ipc_lock(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm);} static inline struct msg_queue *msg_lock_check(struct ipc_namespace *ns, int id){ struct kern_ipc_perm *ipcp = ipc_lock_check(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm);} static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s){ ipc_rmid(&msg_ids(ns), &s->q_perm);} /** * newque - Create a new msg queue * @ns: namespace * @params: ptr to the structure that contains the key and msgflg * * Called with msg_ids.rw_mutex held (writer) */static int newque(struct ipc_namespace *ns, struct ipc_params *params){ struct msg_queue *msq; int id, retval; key_t key = params->key; int msgflg = params->flg; msq = ipc_rcu_alloc(sizeof(*msq)); if (!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) { ipc_rcu_putref(msq); return retval; } /* * ipc_addid() locks msq */ id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni); if (id < 0) { security_msg_queue_free(msq); ipc_rcu_putref(msq); return id; } msq->q_perm.id = msg_buildid(id, msq->q_perm.seq); 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); msg_unlock(msq); return msq->q_perm.id;} static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss){ mss->tsk = current; current->state = TASK_INTERRUPTIBLE; list_add_tail(&mss->list, &msq->q_senders);} static inline void ss_del(struct msg_sender *mss){ if (mss->list.next != NULL) list_del(&mss->list);} static void ss_wakeup(struct list_head *h, int kill){ struct list_head *tmp; tmp = h->next; while (tmp != h) { struct msg_sender *mss; mss = list_entry(tmp, struct msg_sender, list); tmp = tmp->next; if (kill) mss->list.next = NULL; wake_up_process(mss->tsk); }} static void expunge_all(struct msg_queue *msq, int res){ struct list_head *tmp; tmp = msq->q_receivers.next; while (tmp != &msq->q_receivers) { struct msg_receiver *msr; msr = list_entry(tmp, struct msg_receiver, r_list); tmp = tmp->next; msr->r_msg = NULL; wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = ERR_PTR(res); }} /* * 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.rw_mutex (writer) and the spinlock for this message queue are held * before freeque() is called. msg_ids.rw_mutex remains locked on exit. */static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp){ struct list_head *tmp; struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm); expunge_all(msq, -EIDRM); ss_wakeup(&msq->q_senders, 1); msg_rmid(ns, msq); msg_unlock(msq); tmp = msq->q_messages.next; while (tmp != &msq->q_messages) { struct msg_msg *msg = list_entry(tmp, struct msg_msg, m_list); tmp = tmp->next; atomic_dec(&ns->msg_hdrs); free_msg(msg); } atomic_sub(msq->q_cbytes, &ns->msg_bytes); security_msg_queue_free(msq); ipc_rcu_putref(msq);} /* * Called with msg_ids.rw_mutex 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);} asmlinkage long sys_msgget(key_t key, int msgflg){ struct ipc_namespace *ns; struct ipc_ops msg_ops; struct ipc_params msg_params; ns = current->nsproxy->ipc_ns; msg_ops.getnew = newque; msg_ops.associate = msg_security; msg_ops.more_checks = NULL; msg_params.key = key; msg_params.flg = msgflg; return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params);} static inline unsigned longcopy_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; }} struct msq_setbuf { unsigned long qbytes; uid_t uid; gid_t gid; mode_t mode;}; static inline unsigned longcopy_msqid_from_user(struct msq_setbuf *out, void __user *buf, int version){ switch(version) { case IPC_64: { struct msqid64_ds tbuf; if (copy_from_user(&tbuf, buf, sizeof(tbuf))) return -EFAULT; out->qbytes = tbuf.msg_qbytes; out->uid = tbuf.msg_perm.uid; out->gid = tbuf.msg_perm.gid; out->mode = tbuf.msg_perm.mode; return 0; } case IPC_OLD: { struct msqid_ds tbuf_old; if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) return -EFAULT; out->uid = tbuf_old.msg_perm.uid; out->gid = tbuf_old.msg_perm.gid; out->mode = tbuf_old.msg_perm.mode; if (tbuf_old.msg_qbytes == 0) out->qbytes = tbuf_old.msg_lqbytes; else out->qbytes = tbuf_old.msg_qbytes; return 0; } default: return -EINVAL; }} asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf){ struct kern_ipc_perm *ipcp; struct msq_setbuf uninitialized_var(setbuf); struct msg_queue *msq; int err, 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: { 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).rw_mutex); 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).rw_mutex); if (copy_to_user(buf, &msginfo, sizeof(struct msginfo))) return -EFAULT; return (max_id < 0) ? 0 : max_id; } case MSG_STAT: /* msqid is an index rather than a msg queue id */ case IPC_STAT: { struct msqid64_ds tbuf; int success_return; if (!buf) return -EFAULT; if (cmd == MSG_STAT) { msq = msg_lock(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = msq->q_perm.id; } else { msq = msg_lock_check(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = 0; } err = -EACCES; if (ipcperms(&msq->q_perm, S_IRUGO)) goto out_unlock; err = security_msg_queue_msgctl(msq, cmd); if (err) goto out_unlock; memset(&tbuf, 0, sizeof(tbuf)); 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; msg_unlock(msq); if (copy_msqid_to_user(buf, &tbuf, version)) return -EFAULT; return success_return; } case IPC_SET:Lines 1–500 of 948. 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/* * 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/slab.h> #include <linux/msg.h> #include <linux/spinlock.h> #include <linux/init.h> #include <linux/proc_fs.h> #include <linux/list.h> #include <linux/security.h> #include <linux/sched.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 <asm/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 *volatile r_msg; }; /* one msg_sender for each sleeping sender */ struct msg_sender { struct list_head list; struct task_struct *tsk; }; #define SEARCH_ANY 1 #define SEARCH_EQUAL 2 #define SEARCH_NOTEQUAL 3 #define SEARCH_LESSEQUAL 4 #define msg_ids(ns) ((ns)->ids[IPC_MSG_IDS]) #define msg_unlock(msq) ipc_unlock(&(msq)->q_perm) #define msg_buildid(id, seq) ipc_buildid(id, seq) static void freeque(struct ipc_namespace *, struct kern_ipc_perm *); static int newque(struct ipc_namespace *, struct ipc_params *); #ifdef CONFIG_PROC_FS static int sysvipc_msg_proc_show(struct seq_file *s, void *it); #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); } #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); } /* * This routine is called in the paths where the rw_mutex is held to protect * access to the idr tree. */ static inline struct msg_queue *msg_lock_check_down(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_lock_check_down(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm); } /* * msg_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ static inline struct msg_queue *msg_lock(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_lock(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm); } static inline struct msg_queue *msg_lock_check(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_lock_check(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm); } static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s) { ipc_rmid(&msg_ids(ns), &s->q_perm); } /** * newque - Create a new msg queue * @ns: namespace * @params: ptr to the structure that contains the key and msgflg * * Called with msg_ids.rw_mutex held (writer) */ static int newque(struct ipc_namespace *ns, struct ipc_params *params) { struct msg_queue *msq; int id, retval; key_t key = params->key; int msgflg = params->flg; msq = ipc_rcu_alloc(sizeof(*msq)); if (!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) { ipc_rcu_putref(msq); return retval; } /* * ipc_addid() locks msq */ id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni); if (id < 0) { security_msg_queue_free(msq); ipc_rcu_putref(msq); return id; } msq->q_perm.id = msg_buildid(id, msq->q_perm.seq); 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); msg_unlock(msq); return msq->q_perm.id; } static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss) { mss->tsk = current; current->state = TASK_INTERRUPTIBLE; list_add_tail(&mss->list, &msq->q_senders); } static inline void ss_del(struct msg_sender *mss) { if (mss->list.next != NULL) list_del(&mss->list); } static void ss_wakeup(struct list_head *h, int kill) { struct list_head *tmp; tmp = h->next; while (tmp != h) { struct msg_sender *mss; mss = list_entry(tmp, struct msg_sender, list); tmp = tmp->next; if (kill) mss->list.next = NULL; wake_up_process(mss->tsk); } } static void expunge_all(struct msg_queue *msq, int res) { struct list_head *tmp; tmp = msq->q_receivers.next; while (tmp != &msq->q_receivers) { struct msg_receiver *msr; msr = list_entry(tmp, struct msg_receiver, r_list); tmp = tmp->next; msr->r_msg = NULL; wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = ERR_PTR(res); } } /* * 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.rw_mutex (writer) and the spinlock for this message queue are held * before freeque() is called. msg_ids.rw_mutex remains locked on exit. */ static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) { struct list_head *tmp; struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm); expunge_all(msq, -EIDRM); ss_wakeup(&msq->q_senders, 1); msg_rmid(ns, msq); msg_unlock(msq); tmp = msq->q_messages.next; while (tmp != &msq->q_messages) { struct msg_msg *msg = list_entry(tmp, struct msg_msg, m_list); tmp = tmp->next; atomic_dec(&ns->msg_hdrs); free_msg(msg); } atomic_sub(msq->q_cbytes, &ns->msg_bytes); security_msg_queue_free(msq); ipc_rcu_putref(msq); } /* * Called with msg_ids.rw_mutex 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); } asmlinkage long sys_msgget(key_t key, int msgflg) { struct ipc_namespace *ns; struct ipc_ops msg_ops; struct ipc_params msg_params; ns = current->nsproxy->ipc_ns; msg_ops.getnew = newque; msg_ops.associate = msg_security; msg_ops.more_checks = NULL; 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; } } struct msq_setbuf { unsigned long qbytes; uid_t uid; gid_t gid; mode_t mode; }; static inline unsigned long copy_msqid_from_user(struct msq_setbuf *out, void __user *buf, int version) { switch(version) { case IPC_64: { struct msqid64_ds tbuf; if (copy_from_user(&tbuf, buf, sizeof(tbuf))) return -EFAULT; out->qbytes = tbuf.msg_qbytes; out->uid = tbuf.msg_perm.uid; out->gid = tbuf.msg_perm.gid; out->mode = tbuf.msg_perm.mode; return 0; } case IPC_OLD: { struct msqid_ds tbuf_old; if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) return -EFAULT; out->uid = tbuf_old.msg_perm.uid; out->gid = tbuf_old.msg_perm.gid; out->mode = tbuf_old.msg_perm.mode; if (tbuf_old.msg_qbytes == 0) out->qbytes = tbuf_old.msg_lqbytes; else out->qbytes = tbuf_old.msg_qbytes; return 0; } default: return -EINVAL; } } asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf) { struct kern_ipc_perm *ipcp; struct msq_setbuf uninitialized_var(setbuf); struct msg_queue *msq; int err, 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: { 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).rw_mutex); 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).rw_mutex); if (copy_to_user(buf, &msginfo, sizeof(struct msginfo))) return -EFAULT; return (max_id < 0) ? 0 : max_id; } case MSG_STAT: /* msqid is an index rather than a msg queue id */ case IPC_STAT: { struct msqid64_ds tbuf; int success_return; if (!buf) return -EFAULT; if (cmd == MSG_STAT) { msq = msg_lock(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = msq->q_perm.id; } else { msq = msg_lock_check(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = 0; } err = -EACCES; if (ipcperms(&msq->q_perm, S_IRUGO)) goto out_unlock; err = security_msg_queue_msgctl(msq, cmd); if (err) goto out_unlock; memset(&tbuf, 0, sizeof(tbuf)); 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; msg_unlock(msq); if (copy_msqid_to_user(buf, &tbuf, version)) return -EFAULT; return success_return; } case IPC_SET: