kernel/linux.git/ipc/sem.c, branch linux-2.6.28.y

System call wrappers part 25

2009-01-18T18:44:00+00:00

commit d5460c9974a321a194aded4a8c4daaac68ea8171 upstream. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

System call wrapper special cases

2009-01-18T18:43:52+00:00

commit 6673e0c3fbeaed2cd08e2fd4a4aa97382d6fedb0 upstream. System calls with an unsigned long long argument can't be converted with the standard wrappers since that would include a cast to long, which in turn means that we would lose the upper 32 bit on 32 bit architectures. Also semctl can't use the standard wrapper since it has a 'union' parameter. So we handle them as special case and add some extra wrappers instead. Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

ipc/sem.c: make free_un() static

2008-10-16T18:21:51+00:00

Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: rewrite undo list locking

2008-07-25T17:53:42+00:00

The attached patch: - reverses the locking order of ulp->lock and sem_lock: Previously, it was first ulp->lock, then inside sem_lock. Now it's the other way around. - converts the undo structure to rcu. Benefits: - With the old locking order, IPC_RMID could not kfree the undo structures. The stale entries remained in the linked lists and were released later. - The patch fixes a a race in semtimedop(): if both IPC_RMID and a semget() that recreates exactly the same id happen between find_alloc_undo() and sem_lock, then semtimedop() would access already kfree'd memory. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Manfred Spraul Reviewed-by: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: convert sem_array.sem_pending to struct list_head

2008-07-25T17:53:42+00:00

sem_array.sem_pending is a double linked list, the attached patch converts it to struct list_head. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Manfred Spraul Reviewed-by: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: remove unused entries from struct sem_queue

2008-07-25T17:53:42+00:00

sem_queue.sma and sem_queue.id were never used, the attached patch removes them. Signed-off-by: Manfred Spraul Reviewed-by: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: convert undo structures to struct list_head

2008-07-25T17:53:42+00:00

The undo structures contain two linked lists, the attached patch replaces them with generic struct list_head lists. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Manfred Spraul Cc: Nadia Derbey Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: sysvsem: implement sys_unshare(CLONE_SYSVSEM)

2008-04-29T15:06:14+00:00

sys_unshare(CLONE_NEWIPC) doesn't handle the undo lists properly, this can cause a kernel memory corruption. CLONE_NEWIPC must detach from the existing undo lists. Fix, part 1: add support for sys_unshare(CLONE_SYSVSEM) The original reason to not support it was the potential (inevitable?) confusion due to the fact that sys_unshare(CLONE_SYSVSEM) has the inverse meaning of clone(CLONE_SYSVSEM). Our two most reasonable options then appear to be (1) fully support CLONE_SYSVSEM, or (2) continue to refuse explicit CLONE_SYSVSEM, but always do it anyway on unshare(CLONE_SYSVSEM). This patch does (1). Changelog: Apr 16: SEH: switch to Manfred's alternative patch which removes the unshare_semundo() function which always refused CLONE_SYSVSEM. Signed-off-by: Manfred Spraul Signed-off-by: Serge E. Hallyn Acked-by: "Eric W. Biederman" Cc: Pavel Emelyanov Cc: Michael Kerrisk Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

IPC: consolidate all xxxctl_down() functions

2008-04-29T15:06:14+00:00

semctl_down(), msgctl_down() and shmctl_down() are used to handle the same set of commands for each kind of IPC. They all start to do the same job (they retrieve the ipc and do some permission checks) before handling the commands on their own. This patch proposes to consolidate this by moving these same pieces of code into one common function called ipcctl_pre_down(). It simplifies a little these xxxctl_down() functions and increases a little the maintainability. Signed-off-by: Pierre Peiffer Acked-by: Serge Hallyn Cc: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

IPC: introduce ipc_update_perm()

2008-04-29T15:06:13+00:00

The IPC_SET command performs the same permission setting for all IPCs. This patch introduces a common ipc_update_perm() function to update these permissions and makes use of it for all IPCs. Signed-off-by: Pierre Peiffer Acked-by: Serge Hallyn Cc: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds