The patch titled
Subject: mm/vmscan.c: fix int overflow in callers of do_shrink_slab()
has been added to the -mm tree. Its filename is
mm-fix-int-overflow-in-callers-of-do_shrink_slab.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-fix-int-overflow-in-callers-of-do_shrink_slab.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-fix-int-overflow-in-callers-of-do_shrink_slab.patch
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------------------------------------------------------
From: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
Subject: mm/vmscan.c: fix int overflow in callers of do_shrink_slab()
do_shrink_slab() returns unsigned long value, and the placing into int
variable cuts high bytes off. Then we compare ret and 0xfffffffe (since
SHRINK_EMPTY is converted to ret type).
Thus a large number of objects returned by do_shrink_slab() may be
interpreted as SHRINK_EMPTY, if low bytes of their value are equal to
0xfffffffe. Fix that by declaration ret as unsigned long in these
functions.
Link: http://lkml.kernel.org/r/153813407177.17544.14888305435570723973.stgit@localhost.localdomain
Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
Reported-by: Cyrill Gorcunov <gorcunov@xxxxxxxxxx>
Acked-by: Cyrill Gorcunov <gorcunov@xxxxxxxxxx>
Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/vmscan.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
--- a/mm/vmscan.c~mm-fix-int-overflow-in-callers-of-do_shrink_slab
+++ a/mm/vmscan.c
@@ -580,8 +580,8 @@ static unsigned long shrink_slab_memcg(g
struct mem_cgroup *memcg, int priority)
{
struct memcg_shrinker_map *map;
- unsigned long freed = 0;
- int ret, i;
+ unsigned long ret, freed = 0;
+ int i;
if (!memcg_kmem_enabled() || !mem_cgroup_online(memcg))
return 0;
@@ -677,9 +677,8 @@ static unsigned long shrink_slab(gfp_t g
struct mem_cgroup *memcg,
int priority)
{
+ unsigned long ret, freed = 0;
struct shrinker *shrinker;
- unsigned long freed = 0;
- int ret;
if (!mem_cgroup_is_root(memcg))
return shrink_slab_memcg(gfp_mask, nid, memcg, priority);
_
Patches currently in -mm which might be from ktkhai@xxxxxxxxxxxxx are
mm-fix-int-overflow-in-callers-of-do_shrink_slab.patch
scripts-tags-add-declare_hashtable.patch
