Dave Hansen d3c97900b4 ipc/shm.c: fix overly aggressive shmdt() when calls span multiple segments ... This is a highly-contrived scenario. But, a single shmdt() call can be induced in to unmapping memory from mulitple shm segments. Example code is here: http://www.sr71.net/~dave/intel/shmfun.c The fix is pretty simple: Record the 'struct file' for the first VMA we encounter and then stick to it. Decline to unmap anything not from the same file and thus the same segment. I found this by inspection and the odds of anyone hitting this in practice are pretty darn small. Lightly tested, but it's a pretty small patch. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Manfred Spraul <manfred@colorfullife.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-12-13 12:42:52 -08:00
..
compat_mq.c	ipc, kernel: use Linux headers	2014-06-06 16:08:14 -07:00
compat.c	ipc: resolve shadow warnings	2014-10-14 02:18:23 +02:00
ipc_sysctl.c	ipc/msg: increase MSGMNI, remove scaling	2014-12-13 12:42:52 -08:00
Makefile	ipc/msg: increase MSGMNI, remove scaling	2014-12-13 12:42:52 -08:00
mq_sysctl.c	ipc: convert use of typedef ctl_table to struct ctl_table	2014-06-06 16:08:16 -07:00
mqueue.c	new helper: audit_file()	2014-11-19 13:01:26 -05:00
msg.c	ipc/msg: increase MSGMNI, remove scaling	2014-12-13 12:42:52 -08:00
msgutil.c	ipc, msg: fix message length check for negative values	2013-11-13 12:09:36 +09:00
namespace.c	ipc/msg: increase MSGMNI, remove scaling	2014-12-13 12:42:52 -08:00
sem.c	ipc/sem.c: change memory barrier in sem_lock() to smp_rmb()	2014-12-13 12:42:52 -08:00
shm.c	ipc/shm.c: fix overly aggressive shmdt() when calls span multiple segments	2014-12-13 12:42:52 -08:00
syscall.c	get rid of union semop in sys_semctl(2) arguments	2013-03-05 15:14:16 -05:00
util.c	ipc/msg: increase MSGMNI, remove scaling	2014-12-13 12:42:52 -08:00
util.h	ipc, kernel: clear whitespace	2014-06-06 16:08:14 -07:00