From dac2939e629e092b9c65a6242f1b1c018e811dc8 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 30 Jul 2018 14:27:15 -0700 Subject: squashfs: more metadata hardening 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 Acked-by: Phillip Lougher Cc: stable@kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/squashfs/block.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/squashfs') diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c index 0cea9b9236d0..82bc942fc437 100644 --- a/fs/squashfs/block.c +++ b/fs/squashfs/block.c @@ -166,6 +166,8 @@ int squashfs_read_data(struct super_block *sb, u64 index, int length, } if (compressed) { + if (!msblk->stream) + goto read_failure; length = squashfs_decompress(msblk, bh, b, offset, length, output); if (length < 0) -- cgit v1.2.3