]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
ipc: sysvsem: force unshare(CLONE_SYSVSEM) when CLONE_NEWIPC
authorManfred Spraul <manfred@colorfullife.com>
Tue, 29 Apr 2008 08:00:59 +0000 (01:00 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 29 Apr 2008 15:06:14 +0000 (08:06 -0700)
commit6013f67fc1a4c7fa5bcab2d39c1eaa3e260c7ac1
tree33f61a88048e659359864ec10104e304d8a97a73
parent9edff4ab1f8d82675277a04e359d0ed8bf14a7b7
ipc: sysvsem: force unshare(CLONE_SYSVSEM) when CLONE_NEWIPC

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 2: perform an implicit CLONE_SYSVSEM in CLONE_NEWIPC.  CLONE_NEWIPC
creates a new IPC namespace, the task cannot access the existing semaphore
arrays after the unshare syscall.  Thus the task can/must detach from the
existing undo list entries, too.

This fixes the kernel corruption, because it makes it impossible that
undo records from two different namespaces are in sysvsem.undo_list.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/fork.c