staging: ti dspbridge: avoid possible NULL dereference panic

When dsp_notifications array is received from user,
dspbridge verifies the array has valid pointers
and dsp_notification structures. However, these
structures contain pointers that need to be
checked for valid handles.

Signed-off-by: Ernesto Ramos <ernesto@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/staging/tidspbridge/pmgr/dspapi.c b/drivers/staging/tidspbridge/pmgr/dspapi.c
index 1b0ab4ab1921..da08dfc64593 100644
--- a/drivers/staging/tidspbridge/pmgr/dspapi.c
+++ b/drivers/staging/tidspbridge/pmgr/dspapi.c
@@ -539,7 +539,7 @@ func_end:
  */
 u32 mgrwrap_wait_for_bridge_events(union trapped_args *args, void *pr_ctxt)
 {
-        int status = 0, real_status = 0;
+        int status = 0;
         struct dsp_notification *anotifications[MAX_EVENTS];
         struct dsp_notification notifications[MAX_EVENTS];
         u32 index, i;
@@ -554,19 +554,21 @@ u32 mgrwrap_wait_for_bridge_events(union trapped_args *args, void *pr_ctxt)
         /* get the events */
         for (i = 0; i < count; i++) {
                 CP_FM_USR(&notifications[i], anotifications[i], status, 1);
-                if (!status) {
-                        /* set the array of pointers to kernel structures */
-                        anotifications[i] = &notifications[i];
+                if (status || !notifications[i].handle) {
+                        status = -EINVAL;
+                        break;
                 }
+                /* set the array of pointers to kernel structures */
+                anotifications[i] = &notifications[i];
         }
         if (!status) {
-                real_status = mgr_wait_for_bridge_events(anotifications, count,
+                status = mgr_wait_for_bridge_events(anotifications, count,
                                                          &index,
                                                          args->args_mgr_wait.
                                                          utimeout);
         }
         CP_TO_USR(args->args_mgr_wait.pu_index, &index, status, 1);
-        return real_status;
+        return status;
 }
 
 /*