On Fri, Dec 08, 2017 at 04:18:58AM +0000, Ben Hutchings wrote:
On Thu, 2017-12-07 at 14:07 +0100, Greg Kroah-Hartman wrote:
4.4-stable review patch. If anyone has any objections, please let me know.
From: Benjamin Coddington bcodding@redhat.com
[ Upstream commit 4b09ec4b14a168bf2c687e1f598140c3c11e9222 ]
I have reports of a crash that look like __fput() was called twice for a NFSv4.0 file. It seems possible that the state manager could try to reclaim a lock and take a reference on the fl->fl_file at the same time the file is being released if, during the close(), a signal interrupts the wait for outstanding IO while removing locks which then skips the removal of that lock.
Since 83bfff23e9ed ("nfs4: have do_vfs_lock take an inode pointer") has removed the need to traverse fl->fl_file->f_inode in nfs4_lock_done(), taking that reference is no longer necessary.
[...]
No objection to this in 4.4, but that other commit only went into 4.2 so this fix doesn't look suitable for 3.18.
Good catch, now dropped, thanks.
greg k-h