get_mm_rss() atomically dereferences the actual without checking for a
NULL pointer, which is possible since task_lock() is not held.
Cc: San Mehat <san@android.com>
Signed-off-by: David Rientjes <rientjes@google.com>
---
drivers/staging/android/lowmemorykiller.c | 10 ++++++++--
1 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/android/lowmemorykiller.c b/drivers/staging/android/lowmemorykiller.c
--- a/drivers/staging/android/lowmemorykiller.c
+++ b/drivers/staging/android/lowmemorykiller.c
@@ -92,12 +92,18 @@ static int lowmem_shrink(int nr_to_scan, gfp_t gfp_mask)
for_each_process(p) {
int oom_adj;
- if (!p->mm)
+ task_lock(p);
+ if (!p->mm) {
+ task_unlock(p);
continue;
+ }
oom_adj = p->oomkilladj;
- if (oom_adj < min_adj)
+ if (oom_adj < min_adj) {
+ task_unlock(p);
continue;
+ }
tasksize = get_mm_rss(p->mm);
+ task_unlock(p);
if (tasksize <= 0)
continue;
if (selected) {
--
