shmsrc: is-live=true leads to segfault during state transition
Submitted by Alexander Duda
Link to original bug (#796658)
Description
Conditions:
- property is-live=true
- pipeline goes from playing to paused
Cause:
- gst_shm_src_stop_reading deletes the underlying pipe without locking the object
- gstshmsrc.c#L357: rv = sp_client_recv (self->pipe->pipe, &buf) access invalid pipe