On Mon, 5 Oct 2020 03:44:01 +0200, Jann Horn wrote: > Currently, init_listener() tries to prevent adding a filter with > SECCOMP_FILTER_FLAG_NEW_LISTENER if one of the existing filters already > has a listener. However, this check happens without holding any lock that > would prevent another thread from concurrently installing a new filter > (potentially with a listener) on top of the ones we already have. > > Theoretically, this is also a data race: The plain load from > current->seccomp.filter can race with concurrent writes to the same > location. > > [...]
Applied, thanks! I added the stable CC, but I'd agree: it's not so urgent that I need to get this into Linus's tree ahead of the regular merge window. :) [1/1] seccomp: Make duplicate listener detection non-racy https://git.kernel.org/kees/c/ed2d479d3335 -- Kees Cook