From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:38160 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726579AbeKOIa6 (ORCPT ); Thu, 15 Nov 2018 03:30:58 -0500 From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Vasily Averin , Theodore Ts'o , stable@kernel.org, Sasha Levin , linux-ext4@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 27/27] ext4: missing !bh check in ext4_xattr_inode_write() Date: Wed, 14 Nov 2018 17:25:16 -0500 Message-Id: <20181114222520.99926-27-sashal@kernel.org> In-Reply-To: <20181114222520.99926-1-sashal@kernel.org> References: <20181114222520.99926-1-sashal@kernel.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Vasily Averin [ Upstream commit eb6984fa4ce2837dcb1f66720a600f31b0bb3739 ] According to Ted Ts'o ext4_getblk() called in ext4_xattr_inode_write() should not return bh = NULL The only time that bh could be NULL, then, would be in the case of something really going wrong; a programming error elsewhere (perhaps a wild pointer dereference) or I/O error causing on-disk file system corruption (although that would be highly unlikely given that we had *just* allocated the blocks and so the metadata blocks in question probably would still be in the cache). Fixes: e50e5129f384 ("ext4: xattr-in-inode support") Signed-off-by: Vasily Averin Signed-off-by: Theodore Ts'o Cc: stable@kernel.org # 4.13 Signed-off-by: Sasha Levin --- fs/ext4/xattr.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index 9bc50eef6127..34975e1aa7d2 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -1387,6 +1387,12 @@ static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode, bh = ext4_getblk(handle, ea_inode, block, 0); if (IS_ERR(bh)) return PTR_ERR(bh); + if (!bh) { + WARN_ON_ONCE(1); + EXT4_ERROR_INODE(ea_inode, + "ext4_getblk() return bh = NULL"); + return -EFSCORRUPTED; + } ret = ext4_journal_get_write_access(handle, bh); if (ret) goto out; -- 2.17.1