From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from youngberry.canonical.com ([91.189.89.112]:34674 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752155AbdATO1v (ORCPT ); Fri, 20 Jan 2017 09:27:51 -0500 From: Colin King Subject: [PATCH] xfs: do not call xfs_buf_hash_destroy on a NULL pag Date: Fri, 20 Jan 2017 14:26:42 +0000 Message-Id: <20170120142642.21698-1-colin.king@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: "Darrick J . Wong" , linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org From: Colin Ian King If pag cannot be allocated, the current error exit path will trip a null pointer deference error when calling xfs_buf_hash_destroy with a null pag. Fix this by adding a new error exit lable and jumping to this, avoiding the hash destroy and unnecessary kmem_free on pag. Fixes CoverityScan CID#1397628 ("Dereference after null check") Signed-off-by: Colin Ian King --- fs/xfs/xfs_mount.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 9b9540d..4e66cd19 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -207,7 +207,7 @@ xfs_initialize_perag( pag = kmem_zalloc(sizeof(*pag), KM_MAYFAIL); if (!pag) - goto out_unwind; + goto out_unwind_pags; pag->pag_agno = index; pag->pag_mount = mp; spin_lock_init(&pag->pag_ici_lock); @@ -242,6 +242,7 @@ xfs_initialize_perag( out_unwind: xfs_buf_hash_destroy(pag); kmem_free(pag); +out_unwind_pags: for (; index > first_initialised; index--) { pag = radix_tree_delete(&mp->m_perag_tree, index); xfs_buf_hash_destroy(pag); -- 2.10.2