dspbridge: Check pointer before usage

Commit Message

Andy Shevchenko Sept. 1, 2009, 7:59 a.m. UTC

From: Andy Shevchenko <[e-mail]>

Theoretically list could be deleted before we go into the for loop.
Additionally we could delete list immediately if it becomes empty.

Signed-off-by: Andy Shevchenko <[e-mail]>
---
 drivers/dsp/bridge/rmgr/drv.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

Patch

diff --git a/drivers/dsp/bridge/rmgr/drv.c b/drivers/dsp/bridge/rmgr/drv.c
index d21071c..9f726a6 100644
--- a/drivers/dsp/bridge/rmgr/drv.c
+++ b/drivers/dsp/bridge/rmgr/drv.c
@@ -1545,18 +1545,23 @@  DSP_STATUS DRV_ReleaseResources(u32 dwContext, struct DRV_OBJECT *hDrvObject)
 	for (pszdevNode = (struct DRV_EXT *)DRV_GetFirstDevExtension();
 	    pszdevNode != NULL; pszdevNode = (struct DRV_EXT *)
 	    DRV_GetNextDevExtension((u32)pszdevNode)) {
+		if (!pDRVObject->devNodeString)
+			/* List already deleted */
+			break;
+
 		if ((u32)pszdevNode == dwContext) {
 			/* Found it */
 			/* Delete from the Driver object list */
 			LST_RemoveElem(pDRVObject->devNodeString,
-				      (struct LST_ELEM *)pszdevNode);
+				       (struct LST_ELEM *) pszdevNode);
 			MEM_Free((void *) pszdevNode);
-			break;
 		}
+
 		/* Delete the List if it is empty */
 		if (LST_IsEmpty(pDRVObject->devNodeString)) {
 			LST_Delete(pDRVObject->devNodeString);
 			pDRVObject->devNodeString = NULL;
+			break;
 		}
 	}
 	return status;