4.9-stable review patch. If anyone has any objections, please let me know.
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From: Linus Torvalds torvalds@linux-foundation.org
commit d512584780d3e6a7cacb2f482834849453d444a1 upstream.
Anatoly reports another squashfs fuzzing issue, where the decompression parameters themselves are in a compressed block.
This causes squashfs_read_data() to be called in order to read the decompression options before the decompression stream having been set up, making squashfs go sideways.
Reported-by: Anatoly Trosinenko anatoly.trosinenko@gmail.com Acked-by: Phillip Lougher phillip.lougher@gmail.com Cc: stable@kernel.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/squashfs/block.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/fs/squashfs/block.c +++ b/fs/squashfs/block.c @@ -166,6 +166,8 @@ int squashfs_read_data(struct super_bloc }
if (compressed) { + if (!msblk->stream) + goto read_failure; length = squashfs_decompress(msblk, bh, b, offset, length, output); if (length < 0)