Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758185Ab2BISB6 (ORCPT ); Thu, 9 Feb 2012 13:01:58 -0500 Received: from mailhub.sw.ru ([195.214.232.25]:35504 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758160Ab2BISB4 (ORCPT ); Thu, 9 Feb 2012 13:01:56 -0500 Subject: [PATCH 3/5] ipc: add new SHM_SET command for sys_shmctl() call To: akpm@linux-foundation.org From: Stanislav Kinsbursky Cc: jmorris@namei.org, linux-kernel@vger.kernel.org, criu@openvz.org, linux-security-module@vger.kernel.org, viro@zeniv.linux.org.uk, eparis@parisplace.org, sds@tycho.nsa.gov Date: Thu, 09 Feb 2012 22:01:41 +0400 Message-ID: <20120209180141.24392.72036.stgit@localhost6.localdomain6> In-Reply-To: <20120209175043.24392.62810.stgit@localhost6.localdomain6> References: <20120209175043.24392.62810.stgit@localhost6.localdomain6> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3779 Lines: 118 New SHM_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 --- include/linux/shm.h | 1 + ipc/compat.c | 1 + ipc/shm.c | 13 +++++++++++-- security/selinux/hooks.c | 1 + security/smack/smack_lsm.c | 1 + 5 files changed, 15 insertions(+), 2 deletions(-) diff --git a/include/linux/shm.h b/include/linux/shm.h index 92808b8..6fc5447 100644 --- a/include/linux/shm.h +++ b/include/linux/shm.h @@ -63,6 +63,7 @@ struct shmid_ds { /* ipcs ctl commands */ #define SHM_STAT 13 #define SHM_INFO 14 +#define SHM_SET 15 /* Obsolete, used only for backwards compatibility */ struct shminfo { diff --git a/ipc/compat.c b/ipc/compat.c index 43f3596..fc378d9 100644 --- a/ipc/compat.c +++ b/ipc/compat.c @@ -630,6 +630,7 @@ long compat_sys_shmctl(int first, int second, void __user *uptr) case IPC_SET: + case SHM_SET: if (version == IPC_64) { err = get_compat_shmid64_ds(&s64, uptr); } else { diff --git a/ipc/shm.c b/ipc/shm.c index 67ed2e2..20fe8f5 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -623,6 +623,9 @@ copy_shmid_from_user(struct shmid64_ds *out, void __user *buf, int version) out->shm_perm.uid = tbuf_old.shm_perm.uid; out->shm_perm.gid = tbuf_old.shm_perm.gid; out->shm_perm.mode = tbuf_old.shm_perm.mode; + out->shm_perm.cuid = tbuf_old.shm_perm.cuid; + out->shm_perm.cgid = tbuf_old.shm_perm.cgid; + out->shm_perm.key = tbuf_old.shm_perm.key; return 0; } @@ -727,12 +730,13 @@ static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd, struct shmid_kernel *shp; int err; - if (cmd == IPC_SET) { + if (cmd == IPC_SET || cmd == SHM_SET) { if (copy_shmid_from_user(&shmid64, buf, version)) return -EFAULT; } - ipcp = ipcctl_pre_down(ns, &shm_ids(ns), shmid, cmd, + ipcp = ipcctl_pre_down(ns, &shm_ids(ns), shmid, + (cmd != SHM_SET) ? : IPC_SET, &shmid64.shm_perm, 0); if (IS_ERR(ipcp)) return PTR_ERR(ipcp); @@ -746,6 +750,10 @@ static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd, case IPC_RMID: do_shm_rmid(ns, ipcp); goto out_up; + case SHM_SET: + err = ipc_update_key(&shm_ids(ns), &shmid64.shm_perm, ipcp); + if (err) + break; case IPC_SET: ipc_update_perm(&shmid64.shm_perm, ipcp); shp->shm_ctim = get_seconds(); @@ -923,6 +931,7 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) } case IPC_RMID: case IPC_SET: + case SHM_SET: err = shmctl_down(ns, shmid, cmd, buf, version); return err; default: diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 6a3683e..1728a5e 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4991,6 +4991,7 @@ static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) perms = SHM__GETATTR | SHM__ASSOCIATE; break; case IPC_SET: + case SHM_SET: perms = SHM__SETATTR; break; case SHM_LOCK: diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index e8af5b0b..4765659 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -2197,6 +2197,7 @@ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) may = MAY_READ; break; case IPC_SET: + case SHM_SET: case SHM_LOCK: case SHM_UNLOCK: case IPC_RMID: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/