diff options
| author | Jari Ruusu <jariruusu@users.sourceforge.net> | 2015-06-13 19:01:31 +0300 |
|---|---|---|
| committer | Moyster <oysterized@gmail.com> | 2016-08-26 19:15:12 +0200 |
| commit | bd9b56cf9d77016a3c3edc43c421a300bc37254e (patch) | |
| tree | 9fd9919911af0996a6a1a0a7a52779f7c91d1bfb | |
| parent | 8fc061d60e836c43d4be22862f1cd37afebcf84a (diff) | |
d_walk() might skip too much
When Al Viro's VFS deadlock fix "deal with deadlock in d_walk()" was
backported to 3.10.y 3.4.y and 3.2.y stable kernel brances, the deadlock fix
was copied to 3 different places. Later, a bug in that code was discovered.
Al Viro's fix involved fixing only one part of code in mainline kernel. That
fix is called "d_walk() might skip too much".
3.10.y 3.4.y and 3.2.y stable kernel brances need that later fix copied to 3
different places. Greg Kroah-Hartman included Al Viro's "d_walk() might skip
too much" fix only once in 3.10.80 kernel, leaving 2 more places without a
fix.
The patch below was not written by me. I only applied Al Viro's "d_walk()
might skip too much" fix 2 more times to 3.10.80 kernel, and cheched that
the fixes went to correct places. With this patch applied, all 3 places that
I am aware of 3.10.y stable branch are now fixed.
Signed-off-by: Jari Ruusu <jariruusu@users.sourceforge.net>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Guendhoer <stefan@guendhoer.com>
| -rw-r--r-- | fs/dcache.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index e2800926a..38c4a302f 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1053,13 +1053,13 @@ 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; } @@ -2977,13 +2977,13 @@ 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; } |