diff options
| author | Nick Piggin <npiggin@suse.de> | 2007-11-15 12:32:04 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-11-15 08:36:27 -0800 |
| commit | d32ddd8f20e7d7a49c45c337c2079be03c77dc41 (patch) | |
| tree | a56dae80e045a8928bb8da74e6edb3874d297ee2 /mm/slob.c | |
| parent | a3474224e6a01924be40a8255636ea5522c1023a (diff) | |
| download | lwn-d32ddd8f20e7d7a49c45c337c2079be03c77dc41.tar.gz lwn-d32ddd8f20e7d7a49c45c337c2079be03c77dc41.zip | |
slob: fix memory corruption
Previously, it would be possible for prev->next to point to
&free_slob_pages, and thus we would try to move a list onto itself, and
bad things would happen.
It seems a bit hairy to be doing list operations with the list marker as
an entry, rather than a head, but...
this resolves the following crash:
http://bugzilla.kernel.org/show_bug.cgi?id=9379
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/slob.c')
| -rw-r--r-- | mm/slob.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/mm/slob.c b/mm/slob.c index 5bc2ceb692ec..08a9bd91a1aa 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -321,7 +321,8 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node) /* Improve fragment distribution and reduce our average * search time by starting our next search here. (see * Knuth vol 1, sec 2.5, pg 449) */ - if (free_slob_pages.next != prev->next) + if (prev != free_slob_pages.prev && + free_slob_pages.next != prev->next) list_move_tail(&free_slob_pages, prev->next); break; } |