From eb66b8abae98f869c224f7c852b685ae02144564 Mon Sep 17 00:00:00 2001 From: Lizhi Xu Date: Thu, 16 Nov 2023 11:13:52 +0800 Subject: squashfs: squashfs_read_data need to check if the length is 0 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@windriver.com Reported-by: syzbot+32d3767580a1ea339a81@syzkaller.appspotmail.com Closes: https://lkml.kernel.org/r/0000000000000526f2060a30a085@google.com Signed-off-by: Lizhi Xu Reviewed-by: Phillip Lougher Signed-off-by: Andrew Morton --- fs/squashfs/block.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/squashfs') diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c index 581ce9519339..2dc730800f44 100644 --- a/fs/squashfs/block.c +++ b/fs/squashfs/block.c @@ -321,7 +321,7 @@ 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; -- cgit