From: Johannes Thumshirn <jthumshirn@xxxxxxx> [ Upstream commit 0bc315381fe9ed9fb91db8b0e82171b645ac008f ] zram can handle at most SECTORS_PER_PAGE sectors in a bio's bvec. When using the NVMe over Fabrics loopback target which potentially sends a huge bulk of pages attached to the bio's bvec this results in a kernel panic because of array out of bounds accesses in zram_decompress_page(). Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> --- drivers/block/zram/zram_drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index c9914d653968..b7c0b69a02f5 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1286,6 +1286,8 @@ static int zram_add(void) blk_queue_io_min(zram->disk->queue, PAGE_SIZE); blk_queue_io_opt(zram->disk->queue, PAGE_SIZE); zram->disk->queue->limits.discard_granularity = PAGE_SIZE; + zram->disk->queue->limits.max_sectors = SECTORS_PER_PAGE; + zram->disk->queue->limits.chunk_sectors = 0; blk_queue_max_discard_sectors(zram->disk->queue, UINT_MAX); /* * zram_bio_discard() will clear all logical blocks if logical block -- 2.11.0