From 9b873bdaae64bddade9d8c6df23c8a31948d47d0 Mon Sep 17 00:00:00 2001 From: Andreas Hindborg Date: Mon, 3 Jun 2024 21:26:45 +0200 Subject: [PATCH] null_blk: fix validation of block size [ Upstream commit c462ecd659b5fce731f1d592285832fd6ad54053 ] Block size should be between 512 and PAGE_SIZE and be a power of 2. The current check does not validate this, so update the check. Without this patch, null_blk would Oops due to a null pointer deref when loaded with bs=1536 [1]. Link: https://lore.kernel.org/all/87wmn8mocd.fsf@metaspace.dk/ Signed-off-by: Andreas Hindborg Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20240603192645.977968-1-nmi@metaspace.dk [axboe: remove unnecessary braces and != 0 check] Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/block/null_blk/main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index ec78d9ad3e9b..23c4a7b3d4e5 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -1749,8 +1749,8 @@ static int null_validate_conf(struct nullb_device *dev) return -EINVAL; } - dev->blocksize = round_down(dev->blocksize, 512); - dev->blocksize = clamp_t(unsigned int, dev->blocksize, 512, 4096); + if (blk_validate_block_size(dev->blocksize)) + return -EINVAL; if (dev->queue_mode == NULL_Q_MQ && dev->use_per_node_hctx) { if (dev->submit_queues != nr_online_nodes)