This is a note to let you know that I've just added the patch titled
null_blk: fix validation of block size
to the 6.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
null_blk-fix-validation-of-block-size.patch
and it can be found in the queue-6.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 781cbd1726a43a950c4f0c863fafb8b124a3499b
Author: Andreas Hindborg <a.hindborg@xxxxxxxxxxx>
Date: Mon Jun 3 21:26:45 2024 +0200
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@xxxxxxxxxxxx/
Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxxx>
Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240603192645.977968-1-nmi@xxxxxxxxxxxx
[axboe: remove unnecessary braces and != 0 check]
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 620679a0ac381..26e2c22a87e1c 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1810,8 +1810,8 @@ static int null_validate_conf(struct nullb_device *dev)
dev->queue_mode = NULL_Q_MQ;
}
- 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->use_per_node_hctx) {
if (dev->submit_queues != nr_online_nodes)
