erofs: don't trigger WARN() when decompression fails

[ Upstream commit a0961f351d82d43ab0b845304caa235dfe249ae9 ]

syzbot reported a WARNING [1] due to corrupted compressed data.

As Dmitry said, "If this is not a kernel bug, then the code should
not use WARN. WARN if for kernel bugs and is recognized as such by
all testing systems and humans."

[1] https://lore.kernel.org/r/000000000000b3586105cf0ff45e@google.com

Link: https://lore.kernel.org/r/20211025074311.130395-1-hsiangkao@linux.alibaba.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Reported-by: syzbot+d8aaffc3719597e8cfb4@syzkaller.appspotmail.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index a5bc4b1b7813e9a2b82e119074ef81336c004adf..ad3f31380e6b2a858410b4c7abe1a1b29528ad16 100644 (file)
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -233,7 +233,6 @@ static int z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq, u8 *out)
                erofs_err(rq->sb, "failed to decompress %d in[%u, %u] out[%u]",
                          ret, rq->inputsize, inputmargin, rq->outputsize);
 
-               WARN_ON(1);
                print_hex_dump(KERN_DEBUG, "[ in]: ", DUMP_PREFIX_OFFSET,
                               16, 1, src + inputmargin, rq->inputsize, true);
                print_hex_dump(KERN_DEBUG, "[out]: ", DUMP_PREFIX_OFFSET,