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 AF6AD13341F; Wed, 7 Feb 2024 21:25:08 +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=1707341108; cv=none; b=tAdQCpLX0O5O2uv3idCgRl2zNKLVwiHg6+9l39SIx68AYjhWlBhfhJnqXYA4RvW4l86+dX+94Gks0HO6JQjnT39u52YIXbzkHeYUBEiPkQFXf34mU7K1RhmSI1CxbAH1nvtss0jT6XdqcQKD3VkCYirFFpGQ1ic81yekf6Sy3mk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707341108; c=relaxed/simple; bh=g7u/qMn62pEOd+LB48m+zlQpkYBe2bD/cvBPLtjxmu4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=gQxCHXT2da9RAaWGsoAmfP8IwI9hqGXbyrss1DMBf29QVPBa8T/T8cC9pqOYwcpRUbMDnHSRDlS9VdOUccvVpBSNvJHS0LC9WM5Y049Vw+2MFvwrRtqeSrLL43vwsE0fcVM/K0+wOd4y/CNqORHGOtogGE3ogAUaPgdPT3jk9CM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aaqvFf4/; 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="aaqvFf4/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 141E8C433F1; Wed, 7 Feb 2024 21:25:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1707341108; bh=g7u/qMn62pEOd+LB48m+zlQpkYBe2bD/cvBPLtjxmu4=; h=From:To:Cc:Subject:Date:From; b=aaqvFf4/gI5ufx92FdftOjUMk/zxw4VTEan4bSJg90Yg5YcF4qpaUmsahym6jdQmX /4bvf5/oe6xgYXZton1ShuJtZbrDgqSZqeeckQYSxh777Y7B0GtKaQtOUowoi6FqIf WWZMy6bELRDQcBpNR6n+6b+H3oJgB0hVvclIcRmhcUEa//6uetTku/OYDjBodU4YnF Kr5xlPLXBoy2vKRlStEjQPSXarFT6qzMWj71YGUJ61SFX48VQ0AQRnZZ7yDyft2FR4 32xja9RzZLi+YIKX1k0zmNgw7myP9LW4m2vl15t0FIycO2KzllwV0ReX38ys53rZUq Ebt8MRUGiGvEQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Baokun Li , Jan Kara , Theodore Ts'o , Sasha Levin , adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org Subject: [PATCH AUTOSEL 6.1 01/29] ext4: avoid dividing by 0 in mb_update_avg_fragment_size() when block bitmap corrupt Date: Wed, 7 Feb 2024 16:24:26 -0500 Message-ID: <20240207212505.3169-1-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.77 Content-Transfer-Encoding: 8bit From: Baokun Li [ Upstream commit 993bf0f4c393b3667830918f9247438a8f6fdb5b ] Determine if bb_fragments is 0 instead of determining bb_free to eliminate the risk of dividing by zero when the block bitmap is corrupted. Signed-off-by: Baokun Li Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20240104142040.2835097-6-libaokun1@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/mballoc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 33be702d6e38..779555925029 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -831,7 +831,7 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp) struct ext4_sb_info *sbi = EXT4_SB(sb); int new_order; - if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_free == 0) + if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_fragments == 0) return; new_order = mb_avg_fragment_size_order(sb, -- 2.43.0