6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lizhi Xu <lizhi.xu@xxxxxxxxxxxxx> [ Upstream commit eb66b8abae98f869c224f7c852b685ae02144564 ] When the length passed in is 0, the pagemap_scan_test_walk() caller should bail. This error causes at least a WARN_ON(). Link: https://lkml.kernel.org/r/20231116031352.40853-1-lizhi.xu@xxxxxxxxxxxxx Reported-by: syzbot+32d3767580a1ea339a81@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://lkml.kernel.org/r/0000000000000526f2060a30a085@xxxxxxxxxx Signed-off-by: Lizhi Xu <lizhi.xu@xxxxxxxxxxxxx> Reviewed-by: Phillip Lougher <phillip@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/squashfs/block.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c index 833aca92301f0..45ea5d62cef42 100644 --- a/fs/squashfs/block.c +++ b/fs/squashfs/block.c @@ -198,7 +198,7 @@ int squashfs_read_data(struct super_block *sb, u64 index, int length, TRACE("Block @ 0x%llx, %scompressed size %d\n", index - 2, compressed ? "" : "un", length); } - if (length < 0 || length > output->length || + if (length <= 0 || length > output->length || (index + length) > msblk->bytes_used) { res = -EIO; goto out; -- 2.43.0