diff --git a/include/uapi/linux/shm.h b/include/uapi/linux/shm.h index 4de12a39b07506..dde1344f047cf0 100644 --- a/include/uapi/linux/shm.h +++ b/include/uapi/linux/shm.h @@ -83,8 +83,9 @@ struct shmid_ds { #define SHM_UNLOCK 12 /* ipcs ctl commands */ -#define SHM_STAT 13 -#define SHM_INFO 14 +#define SHM_STAT 13 +#define SHM_INFO 14 +#define SHM_STAT_ANY 15 /* Obsolete, used only for backwards compatibility */ struct shminfo { diff --git a/ipc/shm.c b/ipc/shm.c index acefe44fefefa1..1a28b6a9644949 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -947,14 +947,14 @@ static int shmctl_stat(struct ipc_namespace *ns, int shmid, memset(tbuf, 0, sizeof(*tbuf)); rcu_read_lock(); - if (cmd == SHM_STAT) { + if (cmd == SHM_STAT || cmd == SHM_STAT_ANY) { shp = shm_obtain_object(ns, shmid); if (IS_ERR(shp)) { err = PTR_ERR(shp); goto out_unlock; } id = shp->shm_perm.id; - } else { + } else { /* IPC_STAT */ shp = shm_obtain_object_check(ns, shmid); if (IS_ERR(shp)) { err = PTR_ERR(shp); @@ -962,9 +962,20 @@ static int shmctl_stat(struct ipc_namespace *ns, int shmid, } } - err = -EACCES; - if (ipcperms(ns, &shp->shm_perm, S_IRUGO)) - goto out_unlock; + /* + * Semantically SHM_STAT_ANY ought to be identical to + * that functionality provided by the /proc/sysvipc/ + * interface. As such, only audit these calls and + * do not do traditional S_IRUGO permission checks on + * the ipc object. + */ + if (cmd == SHM_STAT_ANY) + audit_ipc_obj(&shp->shm_perm); + else { + err = -EACCES; + if (ipcperms(ns, &shp->shm_perm, S_IRUGO)) + goto out_unlock; + } err = security_shm_shmctl(&shp->shm_perm, cmd); if (err) @@ -1104,6 +1115,7 @@ long ksys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf) return err; } case SHM_STAT: + case SHM_STAT_ANY: case IPC_STAT: { err = shmctl_stat(ns, shmid, cmd, &sem64); if (err < 0) @@ -1282,6 +1294,7 @@ long compat_ksys_shmctl(int shmid, int cmd, void __user *uptr) return err; } case IPC_STAT: + case SHM_STAT_ANY: case SHM_STAT: err = shmctl_stat(ns, shmid, cmd, &sem64); if (err < 0) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 1eeb70e439d799..1287013f747d89 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6157,6 +6157,7 @@ static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); case IPC_STAT: case SHM_STAT: + case SHM_STAT_ANY: perms = SHM__GETATTR | SHM__ASSOCIATE; break; case IPC_SET: diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 73549007bf9e63..0daab301902348 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3046,6 +3046,7 @@ static int smack_shm_shmctl(struct kern_ipc_perm *isp, int cmd) switch (cmd) { case IPC_STAT: case SHM_STAT: + case SHM_STAT_ANY: may = MAY_READ; break; case IPC_SET: