From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> commit 8f9e86ee795971eabbf372e6d804d6b8578287a7 upstream. syzbot found that a thread can stall for minutes inside ion_system_heap_allocate() after that thread was killed by SIGKILL [1]. Let's check for SIGKILL before doing memory allocation. [1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Reported-by: syzbot <syzbot+8ab2d0f39fb79fe6ca40@xxxxxxxxxxxxxxxxxxxxxxxxx> Acked-by: Laura Abbott <labbott@xxxxxxxxxx> Acked-by: Sumit Semwal <sumit.semwal@xxxxxxxxxx> Link: https://lore.kernel.org/r/d088f188-5f32-d8fc-b9a0-0b404f7501cc@xxxxxxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/android/ion/ion_page_pool.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/staging/android/ion/ion_page_pool.c +++ b/drivers/staging/android/ion/ion_page_pool.c @@ -8,11 +8,14 @@ #include <linux/list.h> #include <linux/slab.h> #include <linux/swap.h> +#include <linux/sched/signal.h> #include "ion.h" static inline struct page *ion_page_pool_alloc_pages(struct ion_page_pool *pool) { + if (fatal_signal_pending(current)) + return NULL; return alloc_pages(pool->gfp_mask, pool->order); }
