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 987492F260C; Sat, 12 Sep 2026 19:27:10 +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=1789241231; cv=none; b=gXn5PWofuusTumV5EzsiS5CdV29+WBzNz0PGIctSwwqi8vtheznh/gR2TXyRmrV8v1utYMbhMzlPP9VI4z9I7SyKQv9E8unnxkoD58H5gQhTKDjewYY7+DUimYfx91IuYkM6lyIovu7lnHilGLKY9vk0UlZjWm3UlAeebqAoFBQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789241231; c=relaxed/simple; bh=d2xFusICcFGawnbuJcxzg3ORyw/94uQrPH9E1EI4xUw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=j8QaIAxFVl7IsDLphfv4uUpm09MEHpRDTJo7cx0YUGWzs2pvaE70X/MvUfwN88FLK8Wze1tTwyzT3/YFyqkiCPlpeo06nx7kuxWjKMGjHgiPKp7g/XS/G8vz04KZts3VnGDb755jl0sb7gyVyuQh9KgMbN1pVKlWWuNwQsE2888= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jXl6PKG2; 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="jXl6PKG2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C3291F000FF; Sat, 12 Sep 2026 19:27:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789241230; bh=ntorAuPlF+Dep00A74yy6QVnuRK84Atl8fCvn0b/+uk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jXl6PKG28YgmMhkRWGcpKjSqmVQDnyUqfgyA0Bou/biZFdMoutfC8IX0eQd6qK0iL YgNw3mFo6iUVQ4M+95o1IzIoYZ9lwRMf7KxYHCaEu/bEtEpVz/LTznySISMmMBk+W/ NIBkHpfH7au170+zdvli7ljS+v2EWFjOub+drta4= 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 5.10 092/798] md: do overflow check for sb->bblog_shift in super_1_load() Date: Sat, 12 Sep 2026 08:55:20 +0200 Message-ID: <20260912065519.066396655@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065516.948645775@linuxfoundation.org> References: <20260912065516.948645775@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 5.10-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 @@ -1763,6 +1763,13 @@ static int super_1_load(struct md_rdev * rdev->bb_page, REQ_OP_READ, 0, 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);