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 B11B929B218; Thu, 3 Apr 2025 19:09:38 +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=1743707378; cv=none; b=suJgHC1pxC1lFfSe7FAdj/Vt4TXbozHzV/QcPEgk5watyR4SQ5ZoTt+UNkDr3kI1U1raR9idXZ2j1dpNLXKVf3g2Uo9V4TbfjZZSokCViaNjFhNY13XaXDi5HfvZd46cWMOUGkf3fgA6BJro2gpkltuxXMShQ8MIyDTi6sY5o90= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743707378; c=relaxed/simple; bh=CwZLU19IRL+MU974j79ornqyCBjoz4krsOIAQ+1GE7w=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=FWQUUa/o2qegvzdaWie70OzQYKnw8pQz94rwgldzu6EbtKsEBl2jWclCBtLbEHmdqHQPEWkgOhV6ZSZFCjpwNzB7ETJFgJYh6fmn8h9Fh5oRTAzykObwmTMcTw031srGVUcd2rZ4whbLZlp1HKARVnwQvbGYtrW57M1qBJtT6XQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YGNQAdTQ; 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="YGNQAdTQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A00DC4CEE3; Thu, 3 Apr 2025 19:09:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743707378; bh=CwZLU19IRL+MU974j79ornqyCBjoz4krsOIAQ+1GE7w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YGNQAdTQSF8KRmsDEM4vmL2Z46bIVCNzYLzoUyo9Nk6NNLPKwoY1FRl859+H4ewsW /tlc4RdlHdZbY7pFzbZrZIxLltjxCUjhHH9zwNTwxgqlRnrDkbskTx6qbU8GlM1fJz qL38uF0yhYoSzfRukRoJUx1PkDRUAZ7Zc+I8ZgS78pf3UWnRSA92bDxAIs0SGUQWrt mMUAYyOqAAOs3VYTqe7w/x4zHKpFtAmquUAEaalC139xcwQVW8qOHnR71CAsvgoOGc tZQ1KnQPQ88fAZXOvnGDj5MMX7sMliUS3yLOs8KenyzhsyGsGo67DPd8ZSyUQDs/f7 DVGiumFSFzCNQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Rand Deeb , Dave Kleikamp , Sasha Levin , shaggy@kernel.org, eadavis@qq.com, ghanshyam1898@gmail.com, niharchaithanya@gmail.com, aha310510@gmail.com, jfs-discussion@lists.sourceforge.net Subject: [PATCH AUTOSEL 5.15 04/16] fs/jfs: Prevent integer overflow in AG size calculation Date: Thu, 3 Apr 2025 15:09:12 -0400 Message-Id: <20250403190924.2678291-4-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250403190924.2678291-1-sashal@kernel.org> References: <20250403190924.2678291-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.15.179 Content-Transfer-Encoding: 8bit From: Rand Deeb [ Upstream commit 7fcbf789629cdb9fbf4e2172ce31136cfed11e5e ] The JFS filesystem calculates allocation group (AG) size using 1 << l2agsize in dbExtendFS(). When l2agsize exceeds 31 (possible with >2TB aggregates on 32-bit systems), this 32-bit shift operation causes undefined behavior and improper AG sizing. On 32-bit architectures: - Left-shifting 1 by 32+ bits results in 0 due to integer overflow - This creates invalid AG sizes (0 or garbage values) in sbi->bmap->db_agsize - Subsequent block allocations would reference invalid AG structures - Could lead to: - Filesystem corruption during extend operations - Kernel crashes due to invalid memory accesses - Security vulnerabilities via malformed on-disk structures Fix by casting to s64 before shifting: bmp->db_agsize = (s64)1 << l2agsize; This ensures 64-bit arithmetic even on 32-bit architectures. The cast matches the data type of db_agsize (s64) and follows similar patterns in JFS block calculation code. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Rand Deeb Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin --- fs/jfs/jfs_dmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c index 38319be806e10..99e9885cbb444 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -3469,7 +3469,7 @@ int dbExtendFS(struct inode *ipbmap, s64 blkno, s64 nblocks) oldl2agsize = bmp->db_agl2size; bmp->db_agl2size = l2agsize; - bmp->db_agsize = 1 << l2agsize; + bmp->db_agsize = (s64)1 << l2agsize; /* compute new number of AG */ agno = bmp->db_numag; -- 2.39.5