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 91F98280A35; Thu, 3 Apr 2025 19:08:09 +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=1743707289; cv=none; b=oPiuHLf72TAQDiJ8e3/s1X4dS/dvXX/zoSUnV+WyPaSwBORkhutwyEGaLhpkvderE7RZgB96U/tvwKSgrtqFx1bC3zrUUiNHb+AMWAD1Q7DVKL+1g/DHjJl4YkQHfpoQjGNEJ3WfgLF27r/wQqYOQ9miclToAhG/XsLfMdefpIE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743707289; c=relaxed/simple; bh=W2ATL21afu9p6lw2AOIcDWMnQ5dX22vrVpbWXYRsq4A=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Wg3SjmirTz04SzDVhfR1JGPQya3rHU0mVwVGd2tgm/sCEZqRwczdEZ1uaFKBhhJ1FZ+MdTdGf85WXwa10rU0QMVZvhYRc4s2vdZL6WCH6LGeTP/Qo1vFhab+HV334NZjG3fXi/VEk8xENVe8FF01LT2mxq/R8kIVyuxS0VW2FuQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NyQ1cPtz; 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="NyQ1cPtz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1307BC4CEE8; Thu, 3 Apr 2025 19:08:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743707289; bh=W2ATL21afu9p6lw2AOIcDWMnQ5dX22vrVpbWXYRsq4A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NyQ1cPtzWg1U4/5cY4mIGzuuU3EZsRSWSH7+0jR+02xZwcZ4byHe3wUAhOWG/nUbp iw+Y9ywqa3WQrn5ruUkbQ344/euCL+grmsdS+Tee6QvhYAinUbiXEaK+V387qtfIBO MMxro1Rp3II2g5aOJm/suR/jn1v7O5dcwmkn0f5XmXwtm4FqzWyvQ6qYfmujea+HAG RSqezsM3WXnLs6TKAUg0Jf03GbKJqF3rlXNExMsZX4dEMivRhdT5UpSGS0a3iAF/D4 0nkUAbuLlVyTtL/17HMCDuxrK78xkRhDBCy0qA+WWPBdAKYuk5mPrLL2sT3CCpQNFZ VqJD8EcEsxQcw== 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, aha310510@gmail.com, ghanshyam1898@gmail.com, peili.dev@gmail.com, rbrasga@uci.edu, niharchaithanya@gmail.com, jfs-discussion@lists.sourceforge.net Subject: [PATCH AUTOSEL 6.6 09/26] fs/jfs: Prevent integer overflow in AG size calculation Date: Thu, 3 Apr 2025 15:07:28 -0400 Message-Id: <20250403190745.2677620-9-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250403190745.2677620-1-sashal@kernel.org> References: <20250403190745.2677620-1-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 6.6.85 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 f89f07c9580ea..9ac1fc2ed05bc 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -3403,7 +3403,7 @@ 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