lkml.org 
[lkml]   [2012]   [Jul]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCHv3] locks: prevent side-effects of locks_release_private before file_lock is initialized
    On Fri, Jul 27, 2012 at 04:45:52PM -0400, J. Bruce Fields wrote:
    > 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).

    (Committing this as well.)--b.

    >
    > --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;
    > --
    > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
    > the body of a message to majordomo@vger.kernel.org
    > More majordomo info at http://vger.kernel.org/majordomo-info.html


    \
     
     \ /
      Last update: 2012-07-29 18:41    [W:0.041 / U:29.952 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site