[PATCH 3.14 039/130] Failing to send a CLOSE if file is opened WRONLY and server reboots on a 4.x mount

From: Greg Kroah-Hartman
Date: Tue Mar 01 2016 - 18:51:23 EST


3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Olga Kornievskaia <aglo@xxxxxxxxx>

commit a41cbe86df3afbc82311a1640e20858c0cd7e065 upstream.

A test case is as the description says:
open(foobar, O_WRONLY);
sleep() --> reboot the server
close(foobar)

The bug is because in nfs4state.c in nfs4_reclaim_open_state() a few
line before going to restart, there is
clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &state->flags).

NFS4CLNT_RECLAIM_NOGRACE is a flag for the client states not open
owner states. Value of NFS4CLNT_RECLAIM_NOGRACE is 4 which is the
value of NFS_O_WRONLY_STATE in nfs4_state->flags. So clearing it wipes
out state and when we go to close it, âcall_closeâ doesnât get set as
state flag is not set and CLOSE doesnât go on the wire.

Signed-off-by: Olga Kornievskaia <aglo@xxxxxxxxx>
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/nfs/nfs4state.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1482,7 +1482,7 @@ restart:
spin_unlock(&state->state_lock);
}
nfs4_put_open_state(state);
- clear_bit(NFS4CLNT_RECLAIM_NOGRACE,
+ clear_bit(NFS_STATE_RECLAIM_NOGRACE,
&state->flags);
spin_lock(&sp->so_lock);
goto restart;