From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 142CB20AF89; Mon, 13 Jan 2025 18:35:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736793345; cv=none; b=OKY4LY5wSAENyf97UYWDQEjlYNge6dLzVMzyqV37SyMzODJ++ZXECV72SpHoWZa6+u3ddQHWpS6Ixt12WIxYU4QN2YtDuTYPteSY2kElJO4RUPAGOSn//ZRVqsysux46MH8nxYPrq7GVBsUV7ywcC2JsoHXXmuwGguczweF2+lI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736793345; c=relaxed/simple; bh=u2zFzAaBRMPWTRzDckQPH3srUU5ZsguO5KNP5zWr598=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=YBNmGsTZt7oiGhKVuQs0qCNQR2fDLo8qXGCLp3rck0oorTwGJQgcudi0dc4xjzsmImxqoBidlVt5Qs6nov/ktQa5e5elXLnWuy8BsScBgXI+AFY6U4PqSL2JH7T7TJuA1R+1HXFkLbqtlqrjDD3m0EwK+BqFPu0GUHWNdnYRC70= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RUoIHblM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RUoIHblM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 741FFC4CEE1; Mon, 13 Jan 2025 18:35:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736793344; bh=u2zFzAaBRMPWTRzDckQPH3srUU5ZsguO5KNP5zWr598=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RUoIHblMs9b2FMaUZbWvS0IIfMOawBQfN/Y6zvB5ORl2qzSDPipjBozT0U4xmQHPN LzGPygXWZ0bixSHAiSE0sFdxQJSOXgbCEiFc4s+Z39m0qXqW1tbzwfngNdhXk0pn0T i5j/4VYbHse4IkGqH2Ea54S99yCqxt4Y7J6x2weamIRIC56bdfPjfK5Qi+/PP2qdNw KQDx73LWOM1lZoB5nE7zt3eOJY2eu+k8BmoE57YZMWy7RYKnyezMCAqQDTKMRY8Z5F oZM0g/npQAPBhP//ozm6cAKBft/FLdTwMX7ma9v+YP5MjNlaQyBaiZWvZpg+vtPr1m wOySNbaQHs0hg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Leo Stone , syzbot+2db3c7526ba68f4ea776@syzkaller.appspotmail.com, Jan Kara , Christian Brauner , Sasha Levin , sandeen@redhat.com, viro@zeniv.linux.org.uk, quic_jjohnson@quicinc.com, linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 6.1 02/10] hfs: Sanity check the root record Date: Mon, 13 Jan 2025 13:35:28 -0500 Message-Id: <20250113183537.1784136-2-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250113183537.1784136-1-sashal@kernel.org> References: <20250113183537.1784136-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.124 Content-Transfer-Encoding: 8bit From: Leo Stone [ Upstream commit b905bafdea21a75d75a96855edd9e0b6051eee30 ] In the syzbot reproducer, the hfs_cat_rec for the root dir has type HFS_CDR_FIL after being read with hfs_bnode_read() in hfs_super_fill(). This indicates it should be used as an hfs_cat_file, which is 102 bytes. Only the first 70 bytes of that struct are initialized, however, because the entrylength passed into hfs_bnode_read() is still the length of a directory record. This causes uninitialized values to be used later on, when the hfs_cat_rec union is treated as the larger hfs_cat_file struct. Add a check to make sure the retrieved record has the correct type for the root directory (HFS_CDR_DIR), and make sure we load the correct number of bytes for a directory record. Reported-by: syzbot+2db3c7526ba68f4ea776@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=2db3c7526ba68f4ea776 Tested-by: syzbot+2db3c7526ba68f4ea776@syzkaller.appspotmail.com Tested-by: Leo Stone Signed-off-by: Leo Stone Link: https://lore.kernel.org/r/20241201051420.77858-1-leocstone@gmail.com Reviewed-by: Jan Kara Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin --- fs/hfs/super.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/hfs/super.c b/fs/hfs/super.c index 6764afa98a6f..431bdc65f723 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -418,11 +418,13 @@ static int hfs_fill_super(struct super_block *sb, void *data, int silent) goto bail_no_root; res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); if (!res) { - if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) { + if (fd.entrylength != sizeof(rec.dir)) { res = -EIO; goto bail_hfs_find; } hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); + if (rec.type != HFS_CDR_DIR) + res = -EIO; } if (res) goto bail_hfs_find; -- 2.39.5