On Thu, Sep 5, 2019 at 1:11 PM Steven Price <steven.price@xxxxxxx> wrote: > > When handling a GPU page fault addr_to_drm_mm_node() is used to > translate the GPU address to a buffer object. However it is possible for > the buffer object to be freed after the function has returned resulting > in a use-after-free of the BO. > > Change addr_to_drm_mm_node to return the panfrost_gem_object with an > extra reference on it, preventing the BO from being freed until after > the page fault has been handled. > > Signed-off-by: Steven Price <steven.price@xxxxxxx> > --- > > I've managed to trigger this, generating the following stack trace. Humm, the assumption was that a fault could only happen during a job and so a reference would already be held. Otherwise, couldn't the GPU also be accessing the BO after it is freed? Also, looking at this again, I think we need to hold the mm_lock around the drm_mm_for_each_node(). Rob _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
