Re: post 2.6.21 regression in F_GETLK

["J. Bruce Fields" <bfields@fieldses.org>]

On Thu, May 10, 2007 at 03:30:50PM -0400, bfields wrote:
> On Thu, May 10, 2007 at 02:56:15PM -0400, Doug Chapman wrote:
> > A recent regression (introduced after 2.6.21) was caught by the LTP test
> > fcntl11.  It appears that F_GETLK is not properly checking for existing
> > F_RDLCK and allows taking out a write lock.
> 
> Ouch.
> 
> > This can be demonstrated by either running fcntl11 from the LTP suite or
> > I have hacked up a much shorter version which demonstrates the issue and
> > am attaching it.
> > 
> > Using git bisect I came up with this commit as the one that introduced
> > the issue.
> 
> Thanks for the report--investigating....

Argh.  Looks like a cut-n-paste error.  Does this fix it?

--b.

diff --git a/fs/locks.c b/fs/locks.c
index 671a034..909f454 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1632,6 +1632,7 @@ static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
 	flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
 		fl->fl_end - fl->fl_start + 1;
 	flock->l_whence = 0;
+	flock->l_type = fl->fl_type;
 	return 0;
 }