From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.136]:53455 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932084AbbIOJLt (ORCPT ); Tue, 15 Sep 2015 05:11:49 -0400 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Al Viro , Zefan Li Subject: [PATCH 3.4 115/146] d_walk() might skip too much Date: Tue, 15 Sep 2015 17:03:50 +0800 Message-Id: <1442307861-32031-115-git-send-email-lizf@kernel.org> In-Reply-To: <1442307787-31952-1-git-send-email-lizf@kernel.org> References: <1442307787-31952-1-git-send-email-lizf@kernel.org> Sender: stable-owner@vger.kernel.org List-ID: From: Al Viro 3.4.109-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 2159184ea01e4ae7d15f2017e296d4bc82d5aeb0 upstream. when we find that a child has died while we'd been trying to ascend, we should go into the first live sibling itself, rather than its sibling. Off-by-one in question had been introduced in "deal with deadlock in d_walk()" and the fix needs to be backported to all branches this one has been backported to. Signed-off-by: Al Viro Signed-off-by: Zefan Li --- fs/dcache.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index 8038a78..d071ea7 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1204,13 +1204,13 @@ ascend: /* might go back up the wrong parent if we have had a rename */ if (!locked && read_seqretry(&rename_lock, seq)) goto rename_retry; - next = child->d_child.next; - while (unlikely(child->d_flags & DCACHE_DENTRY_KILLED)) { + /* go into the first sibling still alive */ + do { + next = child->d_child.next; if (next == &this_parent->d_subdirs) goto ascend; child = list_entry(next, struct dentry, d_child); - next = next->next; - } + } while (unlikely(child->d_flags & DCACHE_DENTRY_KILLED)); rcu_read_unlock(); goto resume; } -- 1.9.1