jtag/drivers/ulink: fix clang static analyzer warnings

scan-build-9:
Description: Potential leak of memory pointed to by 'cmd'
File: /home/vanekt/openocd/scanbuild9/../src/jtag/drivers/ulink.c
Line: 1075

Description: Potential leak of memory pointed to by 'cmd'
File: /home/vanekt/openocd/scanbuild9/../src/jtag/drivers/ulink.c
Line: 1275

ulink_append_xxx_cmd() functions allocate memory for cmd
and then call ulink_allocate_payload(), which allocates cmd->payload_out
or cmd->payload_in.

ulink_append_queue() checks the size of queue and if the new payload
does not fit, calls ulink_execute_queued_commands() and then
ulink_post_process_queue(). If any of these two fails, an error is
returned, allocated cmd struct leaks and the queue is left in an undefined
state.

Change ulink_append_queue() flow to proceed to appending cmd to the queue
even in the case of fail in previous ulink_execute_queued_commands()
or ulink_post_process_queue(). In case of fail then clear the queue
including the last appended cmd.

Change-Id: I967c07af19e9020c93bcb4ef403cf1f557dd1db1
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: http://openocd.zylin.com/5370
Tested-by: jenkins
Reviewed-by: Oleksij Rempel <linux@rempel-privat.de>

diff --git a/src/jtag/drivers/ulink.c b/src/jtag/drivers/ulink.c
index 4066d61091a1d84b1ae7c478213fa5467e3c8a94..c6683abda2bf06c8e47ef478970b69e17f40142b 100644 (file)
--- a/src/jtag/drivers/ulink.c
+++ b/src/jtag/drivers/ulink.c
@@ -650,7 +650,7 @@ void ulink_clear_queue(struct ulink *device)
 int ulink_append_queue(struct ulink *device, struct ulink_cmd *ulink_cmd)
 {
        int newsize_out, newsize_in;
-       int ret;
+       int ret = ERROR_OK;
 
        newsize_out = ulink_get_queue_size(device, PAYLOAD_DIRECTION_OUT) + 1
                + ulink_cmd->payload_out_size;
@@ -663,14 +663,12 @@ int ulink_append_queue(struct ulink *device, struct ulink_cmd *ulink_cmd)
                /* New command does not fit. Execute all commands in queue before starting
                 * new queue with the current command as first entry. */
                ret = ulink_execute_queued_commands(device, USB_TIMEOUT);
-               if (ret != ERROR_OK)
-                       return ret;
 
-               ret = ulink_post_process_queue(device);
-               if (ret != ERROR_OK)
-                       return ret;
+               if (ret == ERROR_OK)
+                       ret = ulink_post_process_queue(device);
 
-               ulink_clear_queue(device);
+               if (ret == ERROR_OK)
+                       ulink_clear_queue(device);
        }
 
        if (device->queue_start == NULL) {
@@ -687,7 +685,10 @@ int ulink_append_queue(struct ulink *device, struct ulink_cmd *ulink_cmd)
                device->queue_end = ulink_cmd;
        }
 
-       return ERROR_OK;
+       if (ret != ERROR_OK)
+               ulink_clear_queue(device);
+
+       return ret;
 }
 
 /**