cifs: send an NT_CANCEL request when a process is signalled

Use the new send_nt_cancel function to send an NT_CANCEL when the
process is delivered a fatal signal. This is a "best effort" enterprise
however, so don't bother to check the return code. There's nothing we
can reasonably do if it fails anyway.

Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 12 insertions, 3 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 9b2d0373a8a7..bdaa4aa58b03 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -570,20 +570,25 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses,
 #endif
 
         mutex_unlock(&ses->server->srv_mutex);
-        cifs_small_buf_release(in_buf);
 
-        if (rc < 0)
+        if (rc < 0) {
+                cifs_small_buf_release(in_buf);
                 goto out;
+        }
 
-        if (long_op == CIFS_ASYNC_OP)
+        if (long_op == CIFS_ASYNC_OP) {
+                cifs_small_buf_release(in_buf);
                 goto out;
+        }
 
         rc = wait_for_response(ses->server, midQ);
         if (rc != 0) {
+                send_nt_cancel(ses->server, in_buf, midQ);
                 spin_lock(&GlobalMid_Lock);
                 if (midQ->midState == MID_REQUEST_SUBMITTED) {
                         midQ->callback = DeleteMidQEntry;
                         spin_unlock(&GlobalMid_Lock);
+                        cifs_small_buf_release(in_buf);
                         atomic_dec(&ses->server->inFlight);
                         wake_up(&ses->server->request_q);
                         return rc;
@@ -591,6 +596,8 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses,
                 spin_unlock(&GlobalMid_Lock);
         }
 
+        cifs_small_buf_release(in_buf);
+
         rc = sync_mid_result(midQ, ses->server);
         if (rc != 0) {
                 atomic_dec(&ses->server->inFlight);
@@ -734,6 +741,7 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
 
         rc = wait_for_response(ses->server, midQ);
         if (rc != 0) {
+                send_nt_cancel(ses->server, in_buf, midQ);
                 spin_lock(&GlobalMid_Lock);
                 if (midQ->midState == MID_REQUEST_SUBMITTED) {
                         /* no longer considered to be "in-flight" */
@@ -943,6 +951,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon,
 
                 rc = wait_for_response(ses->server, midQ);
                 if (rc) {
+                        send_nt_cancel(ses->server, in_buf, midQ);
                         spin_lock(&GlobalMid_Lock);
                         if (midQ->midState == MID_REQUEST_SUBMITTED) {
                                 /* no longer considered to be "in-flight" */