On Thu, Sep 02, 2021 at 08:35:35AM -0700, Todd Kjos wrote:
On Tue, Aug 31, 2021 at 12:24 AM Martijn Coenen maco@android.com wrote:
On Mon, Aug 30, 2021 at 9:51 PM 'Todd Kjos' via kernel-team kernel-team@android.com wrote:
During BC_FREE_BUFFER processing, the BINDER_TYPE_FDA object cleanup may close 1 or more fds. The close operations are completed using the task work mechanism -- which means the thread needs to return to userspace or the file object may never be dereferenced -- which can lead to hung processes.
Force the binder thread back to userspace if an fd is closed during BC_FREE_BUFFER handling.
Signed-off-by: Todd Kjos tkjos@google.com
Reviewed-by: Martijn Coenen maco@android.com
Please also add to stable releases 5.4 and later.
I'll try to remember to tag this as-such after 5.15-rc1 is out and I can apply it to my tree. But in the future, it's best if you add the cc: stable to the patch yourself so I don't have to do it "by hand" after the fact.
thanks,
greg k-h