From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anatoly Trosinenko , Phillip Lougher , stable@kernel.org, Linus Torvalds Subject: [PATCH 3.18 76/85] squashfs: more metadata hardening Date: Tue, 7 Aug 2018 20:52:18 +0200 Message-Id: <20180807172400.180565044@linuxfoundation.org> In-Reply-To: <20180807172357.357252052@linuxfoundation.org> References: <20180807172357.357252052@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Linus Torvalds 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(+) --- 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)