The kev pointers inside the pending events queue (the available queue) of the
fh point to data inside the sev, unsubscribing frees the sev, thus making these
pointers point to freed memory!
This patch fixes these dangling pointers in the available queue by removing
all matching pending events on unsubscription.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/media/video/v4l2-event.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c
index 9f56f18..4d01f17 100644
--- a/drivers/media/video/v4l2-event.c
+++ b/drivers/media/video/v4l2-event.c
@@ -285,6 +285,7 @@ int v4l2_event_unsubscribe(struct v4l2_fh *fh,
{
struct v4l2_subscribed_event *sev;
unsigned long flags;
+ int i;
if (sub->type == V4L2_EVENT_ALL) {
v4l2_event_unsubscribe_all(fh);
@@ -295,6 +296,11 @@ int v4l2_event_unsubscribe(struct v4l2_fh *fh,
sev = v4l2_event_subscribed(fh, sub->type, sub->id);
if (sev != NULL) {
+ /* Remove any pending events for this subscription */
+ for (i = 0; i < sev->in_use; i++) {
+ list_del(&sev->events[sev_pos(sev, i)].list);
+ fh->navailable--;
+ }
list_del(&sev->list);
sev->fh = NULL;
}
--
1.7.7
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
