Commit cb5c2e63 authored by Ronnie Sahlberg's avatar Ronnie Sahlberg Committed by Steve French
Browse files

cifs: fix a credits leak for compund commands 



When processing the mids for compounds we would only add credits based on
the last successful mid in the compound which would leak credits and
eventually triggering a re-connect.

Fix this by splitting the mid processing part into two loops instead of one
where the first loop just waits for all mids and then counts how many
credits we were granted for the whole compound.

Signed-off-by: default avatarRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent b340a4d4

fs/cifs/transport.c

+37 −20
Original line number Diff line number Diff line
@@ -786,7 +786,7 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses, 
	int i, j, rc = 0;

	int timeout, optype;

	struct mid_q_entry *midQ[MAX_COMPOUND];

	unsigned int credits = 1;

	unsigned int credits = 0;

	char *buf;



	timeout = flags & CIFS_TIMEOUT_MASK;
@@ -851,17 +851,20 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses, 


	mutex_unlock(&ses->server->srv_mutex);



	for (i = 0; i < num_rqst; i++) {

	if (rc < 0)

		goto out;



	/*

	 * Compounding is never used during session establish.

	 */

	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP))

			smb311_update_preauth_hash(ses, rqst[i].rq_iov,

						   rqst[i].rq_nvec);

		smb311_update_preauth_hash(ses, rqst[0].rq_iov,

					   rqst[0].rq_nvec);



	if (timeout == CIFS_ASYNC_OP)

		goto out;



	for (i = 0; i < num_rqst; i++) {

		rc = wait_for_response(ses->server, midQ[i]);

		if (rc != 0) {

			cifs_dbg(FYI, "Cancelling wait for mid %llu\n",
@@ -877,10 +880,21 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses, 
			}

			spin_unlock(&GlobalMid_Lock);

		}

	}



	for (i = 0; i < num_rqst; i++)

		if (midQ[i]->resp_buf)

			credits += ses->server->ops->get_credits(midQ[i]);

	if (!credits)

		credits = 1;



	for (i = 0; i < num_rqst; i++) {

		if (rc < 0)

			goto out;



		rc = cifs_sync_mid_result(midQ[i], ses->server);

		if (rc != 0) {

			add_credits(ses->server, 1, optype);

			add_credits(ses->server, credits, optype);

			return rc;

		}
@@ -901,23 +915,26 @@ compound_send_recv(const unsigned int xid, struct cifs_ses *ses, 
		else

			resp_buf_type[i] = CIFS_SMALL_BUFFER;



		if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {

			struct kvec iov = {

				.iov_base = resp_iov[i].iov_base,

				.iov_len = resp_iov[i].iov_len

			};

			smb311_update_preauth_hash(ses, &iov, 1);

		}



		credits = ses->server->ops->get_credits(midQ[i]);



		rc = ses->server->ops->check_receive(midQ[i], ses->server,

						     flags & CIFS_LOG_ERROR);



		/* mark it so buf will not be freed by cifs_delete_mid */

		if ((flags & CIFS_NO_RESP) == 0)

			midQ[i]->resp_buf = NULL;



	}



	/*

	 * Compounding is never used during session establish.

	 */

	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {

		struct kvec iov = {

			.iov_base = resp_iov[0].iov_base,

			.iov_len = resp_iov[0].iov_len

		};

		smb311_update_preauth_hash(ses, &iov, 1);

	}



out:

	/*

	 * This will dequeue all mids. After this it is important that the

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