lkml.org 
[lkml]   [2012]   [Jul]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCHv3] locks: prevent side-effects of locks_release_private before file_lock is initialized
On Fri, Jul 27, 2012 at 12:42:52AM -0400, Filipe Brandenburger wrote:
> When calling fcntl(fd, F_SETLEASE, lck) [with lck=F_WRLCK or F_RDLCK],
> the custom signal or owner (if any were previously set using F_SETSIG
> or F_SETOWN fcntls) would be reset when F_SETLEASE was called for the
> second time on the same file descriptor.
>
> This bug is a regression of 2.6.37 and is described here:
> https://bugzilla.kernel.org/show_bug.cgi?id=43336
>
> This patch reverts a commit from Oct 2004 (with subject "nfs4 lease:
> move the f_delown processing") which originally introduced the
> lm_release_private callback.

Looks fine, thanks. I think can also do something like the following
(on top of your patch).

--b.

commit 96d6d59ceaeaacba4088862f3c57fcd011f52832
Author: J. Bruce Fields <bfields@redhat.com>
Date: Fri Jul 27 16:18:00 2012 -0400

locks: move lease-specific code out of locks_delete_lock

No point putting something only used by one caller into common code.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/locks.c b/fs/locks.c
index 86668dd..541075a 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -570,12 +570,6 @@ static void locks_delete_lock(struct file_lock **thisfl_p)
fl->fl_next = NULL;
list_del_init(&fl->fl_link);

- fasync_helper(0, fl->fl_file, 0, &fl->fl_fasync);
- if (fl->fl_fasync != NULL) {
- printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync);
- fl->fl_fasync = NULL;
- }
-
if (fl->fl_nspid) {
put_pid(fl->fl_nspid);
fl->fl_nspid = NULL;
@@ -1150,6 +1144,11 @@ int lease_modify(struct file_lock **before, int arg)

f_delown(filp);
filp->f_owner.signum = 0;
+ fasync_helper(0, fl->fl_file, 0, &fl->fl_fasync);
+ if (fl->fl_fasync != NULL) {
+ printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync);
+ fl->fl_fasync = NULL;
+ }
locks_delete_lock(before);
}
return 0;

\
 
 \ /
  Last update: 2012-07-27 23:21    [W:0.065 / U:0.928 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site