From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Dmitry Vyukov <dvyukov@google.com>,
        Chao Yu <chao@kernel.org>,
        syzbot+d8aaffc3719597e8cfb4@syzkaller.appspotmail.com,
        Gao Xiang <hsiangkao@linux.alibaba.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.10 257/575] erofs: dont trigger WARN() when decompression fails
Date:   Mon, 15 Nov 2021 17:59:42 +0100
Message-Id: <20211115165352.669147552@linuxfoundation.org>
In-Reply-To: <20211115165343.579890274@linuxfoundation.org>
References: <20211115165343.579890274@linuxfoundation.org>
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From: Gao Xiang <hsiangkao@linux.alibaba.com>

[ 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>
---
 fs/erofs/decompressor.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index cbadbf55c6c20..8a6260aac26cb 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -170,7 +170,6 @@ 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, inlen, inputmargin, rq->outputsize);
 
-		WARN_ON(1);
 		print_hex_dump(KERN_DEBUG, "[ in]: ", DUMP_PREFIX_OFFSET,
 			       16, 1, src + inputmargin, inlen, true);
 		print_hex_dump(KERN_DEBUG, "[out]: ", DUMP_PREFIX_OFFSET,
-- 
2.33.0