staging/lustre/mdc: Initialize req in mdc_enqueue for !it case

Commit ab909585b813 ("staging: lustre: Cleanup variable declarations
in mdc_enqueue()") broke Lustre flock handling introducing access
to uninitialized req variable, leading to bizzare crash in a later
call to __req_capsule_offset with invalid pill value.

Set req to NULL just for this case as in all other cases req is
explicitly initialized with request packing call.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
CC: Srikrishan Malik <srikrishanmalik@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/staging/lustre/lustre/mdc/mdc_locks.c b/drivers/staging/lustre/lustre/mdc/mdc_locks.c
index 8c9b4f5494e9..d1c224ecd2b7 100644
--- a/drivers/staging/lustre/lustre/mdc/mdc_locks.c
+++ b/drivers/staging/lustre/lustre/mdc/mdc_locks.c
@@ -828,6 +828,7 @@ resend:
                          einfo->ei_type);
                 policy = (ldlm_policy_data_t *)lmm;
                 res_id.name[3] = LDLM_FLOCK;
+                req = NULL;
         } else if (it->it_op & IT_OPEN) {
                 req = mdc_intent_open_pack(exp, it, op_data, lmm, lmmsize,
                                            einfo->ei_cbdata);