From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9FA2E41CB47; Fri, 4 Sep 2026 06:13:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788502403; cv=none; b=iOkVqTAI4OmGL50vk4RMNmJ/0bpDTZfsXISs2agz8zX92mBTIM1xKpyoUy9sZ+2tmj5LJoTmWX3Mn7IuevnGhHakB9YMIC/G5d2r9yMK4eD/B4g3z1aYqGFINLar+mQ6BTu6z0KbBBFUoLAMOQErsiStbXlXaWNUthoAPjt0guI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788502403; c=relaxed/simple; bh=0S5usKlvMEhR7mW5s802XqALVg3HZ9sgInSRH4WSNBo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nFPtm+/9wcLfDlGAPbUbgWpkGAbFzVawyJbUIIQC2RsBvghblxJsZH4ie6Cg0Wsyltck+6I81pZ4W+oT2NhnEUDA8SSWO9rwVdhGzRuqPBHi3KBBt9o/yVIQ3MqU54JrA9txAjABkK72lex1NRChmU+1VQsHGSWKlRqwZMKY3uE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=rdTenE2k; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="rdTenE2k" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 055921F00A3D; Fri, 4 Sep 2026 06:13:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788502402; bh=CgRwEa81QCndTrzrC0I/sqeWECe47FYwCVrfGxCfBiM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=rdTenE2k2sMJRkGwubZB7r1tUqwlFGUdl91Oq7xQXkDbcubfQEKjdW/tW5Yohpf00 8ehTKQudwNDo4qyVVeKuLhZ1FLJeSIHNt6BMQghnmb9+8Qm7P0nEU4l+1tvwzLzdeo FlcgeIFyKE0aXdb80hS1ipzkZSBJMcbjlTqIspAI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ramesh Adhikari , Coly Li , Yu Kuai Subject: [PATCH 6.12 196/403] md: do overflow check for sb->bblog_shift in super_1_load() Date: Fri, 4 Sep 2026 06:59:59 +0200 Message-ID: <20260904045739.312354409@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045734.806166532@linuxfoundation.org> References: <20260904045734.806166532@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Coly Li commit 35d522bd32462afcf1981dab6da8a9256c26c1e0 upstream. In super_1_load(), sb->bblog_shift is an __u8 type value loaded from on- disk superblock. It is used for badblocks API badblocks_set() by the following sequence, 1930 rdev->badblocks.shift = sb->bblog_shift; 1931 for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) { 1932 u64 bb = le64_to_cpu(*bbp); 1933 int count = bb & (0x3ff); 1934 u64 sector = bb >> 10; 1935 sector <<= sb->bblog_shift; 1936 count <<= sb->bblog_shift; 1937 if (bb + 1 == 0) 1938 break; 1939 if (!badblocks_set(&rdev->badblocks, sector, count, 1)) 1940 return -EINVAL; 1941 } bb->bblog_shit is in range of 0-255, variable sector is 64bit width, for an invalid bb->bblog_shit, it is possible to make sector be overflowed by the following calculation, 1935 sector <<= sb->bblog_shift; Then in turn when call badblocks_set() at line 1939 with the invalid rdev->badblocks.shift set at line 1930, may result an overflow inside _badblocks_clear() in block/badblocks.c. Although there are many places to call badblocks APIs, the non-zero shift value is only used in super_1_load(), other places always use 0 as the shift value. Therefore it is unnecessary to do a general shift value overflow check inside badblock API, and just check here as the caller. This may avoid unnecessary check, make the badblocks API code more simple and elegant. Fixes: 2699b67223ac ("md: load/store badblock list from v1.x metadata") Fixes: 1726c7746783 ("badblocks: improve badblocks_set() for multiple ranges handling") Cc: stable@vger.kernel.org Cc: Ramesh Adhikari Signed-off-by: Coly Li Reviewed-by: Yu Kuai Link: https://patch.msgid.link/20260720111400.2120834-1-colyli@fygo.io Signed-off-by: Yu Kuai Signed-off-by: Greg Kroah-Hartman --- drivers/md/md.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1756,6 +1756,13 @@ static int super_1_load(struct md_rdev * rdev->bb_page, REQ_OP_READ, true)) return -EIO; bbp = (__le64 *)page_address(rdev->bb_page); + + /* check for badblocks api. */ + if (sb->bblog_shift >= BITS_PER_TYPE(sector_t)) { + pr_err("md: %pg: bogus bblog_shift %u for badblocks.\n", + rdev->bdev, sb->bblog_shift); + return -EINVAL; + } rdev->badblocks.shift = sb->bblog_shift; for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) { u64 bb = le64_to_cpu(*bbp);