The patch titled IPC: fix error check in all new xxx_lock() and xxx_exit_ns() functions has been removed from the -mm tree. Its filename was ipc-fix-error-check-in-all-new-xxx_lock-and.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: IPC: fix error check in all new xxx_lock() and xxx_exit_ns() functions From: Pierre Peiffer <pierre.peiffer@xxxxxxxx> In the new implementation of the [sem|shm|msg]_lock[_check]() routines, we use the return value of ipc_lock() in container_of() without any check. But ipc_lock may return a errcode. The use of this errcode in container_of() may alter this errcode, and we don't want this. And in xxx_exit_ns, the pointer return by idr_find is of type 'struct kern_ipc_per'... Today, the code will work as is because the member used in these container_of() is the first member of its container (offset == 0), the errcode isn't changed then. But in the general case, we can't count on this assumption and this may lead later to a real bug if we don't correct this. Again, the proposed solution is simple and correct. But, as pointed by Nadia, with this solution, the same check will be done several times (in all sub-callers...), what is not very funny/optimal... Signed-off-by: Pierre Peiffer <pierre.peiffer@xxxxxxxx> Cc: Nadia Derbey <Nadia.Derbey@xxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- ipc/msg.c | 17 ++++++++++++++--- ipc/sem.c | 17 ++++++++++++++--- ipc/shm.c | 20 +++++++++++++++++--- 3 files changed, 45 insertions(+), 9 deletions(-) diff -puN ipc/msg.c~ipc-fix-error-check-in-all-new-xxx_lock-and ipc/msg.c --- a/ipc/msg.c~ipc-fix-error-check-in-all-new-xxx_lock-and +++ a/ipc/msg.c @@ -105,6 +105,7 @@ int msg_init_ns(struct ipc_namespace *ns void msg_exit_ns(struct ipc_namespace *ns) { struct msg_queue *msq; + struct kern_ipc_perm *perm; int next_id; int total, in_use; @@ -113,10 +114,11 @@ void msg_exit_ns(struct ipc_namespace *n in_use = msg_ids(ns).in_use; for (total = 0, next_id = 0; total < in_use; next_id++) { - msq = idr_find(&msg_ids(ns).ipcs_idr, next_id); - if (msq == NULL) + perm = idr_find(&msg_ids(ns).ipcs_idr, next_id); + if (perm == NULL) continue; - ipc_lock_by_ptr(&msq->q_perm); + ipc_lock_by_ptr(perm); + msq = container_of(perm, struct msg_queue, q_perm); freeque(ns, msq); total++; } @@ -144,6 +146,9 @@ static inline struct msg_queue *msg_lock { 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); } @@ -155,6 +160,9 @@ static inline struct msg_queue *msg_lock { 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); } @@ -163,6 +171,9 @@ static inline struct msg_queue *msg_lock { 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); } diff -puN ipc/sem.c~ipc-fix-error-check-in-all-new-xxx_lock-and ipc/sem.c --- a/ipc/sem.c~ipc-fix-error-check-in-all-new-xxx_lock-and +++ a/ipc/sem.c @@ -143,6 +143,7 @@ int sem_init_ns(struct ipc_namespace *ns void sem_exit_ns(struct ipc_namespace *ns) { struct sem_array *sma; + struct kern_ipc_perm *perm; int next_id; int total, in_use; @@ -151,10 +152,11 @@ void sem_exit_ns(struct ipc_namespace *n in_use = sem_ids(ns).in_use; for (total = 0, next_id = 0; total < in_use; next_id++) { - sma = idr_find(&sem_ids(ns).ipcs_idr, next_id); - if (sma == NULL) + perm = idr_find(&sem_ids(ns).ipcs_idr, next_id); + if (perm == NULL) continue; - ipc_lock_by_ptr(&sma->sem_perm); + ipc_lock_by_ptr(perm); + sma = container_of(perm, struct sem_array, sem_perm); freeary(ns, sma); total++; } @@ -181,6 +183,9 @@ static inline struct sem_array *sem_lock { struct kern_ipc_perm *ipcp = ipc_lock_check_down(&sem_ids(ns), id); + if (IS_ERR(ipcp)) + return (struct sem_array *)ipcp; + return container_of(ipcp, struct sem_array, sem_perm); } @@ -192,6 +197,9 @@ static inline struct sem_array *sem_lock { struct kern_ipc_perm *ipcp = ipc_lock(&sem_ids(ns), id); + if (IS_ERR(ipcp)) + return (struct sem_array *)ipcp; + return container_of(ipcp, struct sem_array, sem_perm); } @@ -200,6 +208,9 @@ static inline struct sem_array *sem_lock { struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); + if (IS_ERR(ipcp)) + return (struct sem_array *)ipcp; + return container_of(ipcp, struct sem_array, sem_perm); } diff -puN ipc/shm.c~ipc-fix-error-check-in-all-new-xxx_lock-and ipc/shm.c --- a/ipc/shm.c~ipc-fix-error-check-in-all-new-xxx_lock-and +++ a/ipc/shm.c @@ -111,6 +111,7 @@ int shm_init_ns(struct ipc_namespace *ns void shm_exit_ns(struct ipc_namespace *ns) { struct shmid_kernel *shp; + struct kern_ipc_perm *perm; int next_id; int total, in_use; @@ -119,10 +120,11 @@ void shm_exit_ns(struct ipc_namespace *n in_use = shm_ids(ns).in_use; for (total = 0, next_id = 0; total < in_use; next_id++) { - shp = idr_find(&shm_ids(ns).ipcs_idr, next_id); - if (shp == NULL) + perm = idr_find(&shm_ids(ns).ipcs_idr, next_id); + if (perm == NULL) continue; - ipc_lock_by_ptr(&shp->shm_perm); + ipc_lock_by_ptr(perm); + shp = container_of(perm, struct shmid_kernel, shm_perm); do_shm_rmid(ns, shp); total++; } @@ -149,6 +151,9 @@ static inline struct shmid_kernel *shm_l { struct kern_ipc_perm *ipcp = ipc_lock_down(&shm_ids(ns), id); + if (IS_ERR(ipcp)) + return (struct shmid_kernel *)ipcp; + return container_of(ipcp, struct shmid_kernel, shm_perm); } @@ -158,6 +163,9 @@ static inline struct shmid_kernel *shm_l { struct kern_ipc_perm *ipcp = ipc_lock_check_down(&shm_ids(ns), id); + if (IS_ERR(ipcp)) + return (struct shmid_kernel *)ipcp; + return container_of(ipcp, struct shmid_kernel, shm_perm); } @@ -169,6 +177,9 @@ static inline struct shmid_kernel *shm_l { struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id); + if (IS_ERR(ipcp)) + return (struct shmid_kernel *)ipcp; + return container_of(ipcp, struct shmid_kernel, shm_perm); } @@ -177,6 +188,9 @@ static inline struct shmid_kernel *shm_l { struct kern_ipc_perm *ipcp = ipc_lock_check(&shm_ids(ns), id); + if (IS_ERR(ipcp)) + return (struct shmid_kernel *)ipcp; + return container_of(ipcp, struct shmid_kernel, shm_perm); } _ Patches currently in -mm which might be from pierre.peiffer@xxxxxxxx are origin.patch ipc-semaphores-consolidate-sem_stat-and.patch ipc-make-struct-ipc_ids-static-in-ipc_namespace.patch ipc-consolidate-sem_exit_ns-msg_exit_ns-and-shm_exit_ns.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html