[124/289] ipc: shm: fix information leak to userland

Greg KH
2010-12-08T01:01:13Z

From: Vasiliy Kulikov <segooon@gmail.com>

commit 3af54c9bd9e6f14f896aac1bb0e8405ae0bc7a44 upstream.

The shmid_ds structure is copied to userland with shm_unused{,2,3}
fields unitialized. It leads to leaking of contents of kernel stack
memory.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
ipc/shm.c | 1 +
1 file changed, 1 insertion(+)

--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -473,6 +473,7 @@ static inline unsigned long copy_shmid_t
{
struct shmid_ds out;

+ memset(&out, 0, sizeof(out));
ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm);
out.shm_segsz = in->shm_segsz;
out.shm_atime = in->shm_atime;