qubes-linux-kernel/patches.fixes/grab-swap-token-oops
2010-07-07 13:12:45 +02:00

31 lines
732 B
Plaintext

From: Dean Roe <roe@sgi.com>
Subject: Prevent NULL pointer deref in grab_swap_token
References: 159260
Patch-mainline: not yet
grab_swap_token() assumes that the current process has an mm struct,
which is not true for kernel threads invoking get_user_pages(). Since
this should be extremely rare, just return from grab_swap_token()
without doing anything.
Signed-off-by: Dean Roe <roe@sgi.com>
Acked-by: mason@suse.de
Acked-by: okir@suse.de
mm/thrash.c | 3 +++
1 file changed, 3 insertions(+)
--- a/mm/thrash.c
+++ b/mm/thrash.c
@@ -31,6 +31,9 @@ void grab_swap_token(struct mm_struct *m
int current_interval;
global_faults++;
+ if (mm == NULL)
+ return;
+
current_interval = global_faults - mm->faultstamp;