Messages in this thread Patch in this message | | | Subject | [PATCH 5/5] ipc: add new SEM_SET command for sys_semctl() call | From | Stanislav Kinsbursky <> | Date | Thu, 09 Feb 2012 22:01:56 +0400 |
| |
New SEM_SET command will be interpreted exactly as IPC_SET, but also will update key, cuid and cgid values. IOW, it allows to change existent key value. The fact, that key is not used is checked before update. Otherwise -EEXIST is returned.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
--- include/linux/sem.h | 1 + ipc/compat.c | 1 + ipc/sem.c | 10 ++++++++-- security/selinux/hooks.c | 1 + security/smack/smack_lsm.c | 1 + 5 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/include/linux/sem.h b/include/linux/sem.h index 10d6b22..c74b9b5 100644 --- a/include/linux/sem.h +++ b/include/linux/sem.h @@ -18,6 +18,7 @@ /* ipcs ctl cmds */ #define SEM_STAT 18 #define SEM_INFO 19 +#define SEM_SET 20 /* Obsolete, used only for backwards compatibility and libc5 compiles */ struct semid_ds { diff --git a/ipc/compat.c b/ipc/compat.c index 20d639e..b828244 100644 --- a/ipc/compat.c +++ b/ipc/compat.c @@ -289,6 +289,7 @@ long compat_sys_semctl(int first, int second, int third, void __user *uptr) break; case IPC_SET: + case SEM_SET: if (version == IPC_64) { err = get_compat_semid64_ds(&s64, compat_ptr(pad)); } else { diff --git a/ipc/sem.c b/ipc/sem.c index 845c912..d9024d5 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -1084,12 +1084,13 @@ static int semctl_down(struct ipc_namespace *ns, int semid, struct semid64_ds semid64; struct kern_ipc_perm *ipcp; - if(cmd == IPC_SET) { + if (cmd == IPC_SET || cmd == SEM_SET) { if (copy_semid_from_user(&semid64, arg.buf, version)) return -EFAULT; } - ipcp = ipcctl_pre_down(ns, &sem_ids(ns), semid, cmd, + ipcp = ipcctl_pre_down(ns, &sem_ids(ns), semid, + (cmd != SEM_SET) ? : IPC_SET, &semid64.sem_perm, 0); if (IS_ERR(ipcp)) return PTR_ERR(ipcp); @@ -1104,6 +1105,10 @@ static int semctl_down(struct ipc_namespace *ns, int semid, case IPC_RMID: freeary(ns, ipcp); goto out_up; + case SEM_SET: + err = ipc_update_key(&sem_ids(ns), &semid64.sem_perm, ipcp); + if (err) + break; case IPC_SET: ipc_update_perm(&semid64.sem_perm, ipcp); sma->sem_ctime = get_seconds(); @@ -1149,6 +1154,7 @@ SYSCALL_DEFINE(semctl)(int semid, int semnum, int cmd, union semun arg) return err; case IPC_RMID: case IPC_SET: + case SEM_SET: err = semctl_down(ns, semid, cmd, version, arg); return err; default: diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 1428f8d..3bea7e3 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -5097,6 +5097,7 @@ static int selinux_sem_semctl(struct sem_array *sma, int cmd) perms = SEM__DESTROY; break; case IPC_SET: + case SEM_SET: perms = SEM__SETATTR; break; case IPC_STAT: diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 143c053..a4a5d0c 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -2329,6 +2329,7 @@ static int smack_sem_semctl(struct sem_array *sma, int cmd) case SETALL: case IPC_RMID: case IPC_SET: + case SEM_SET: may = MAY_READWRITE; break; case IPC_INFO:
| |