On Mon, 15 Nov 2021 09:52:55 +0100, Christophe Leroy wrote:

The conversion from __copy_from_user() to __get_user() by
commit d3ccc9781560 ("powerpc/signal: Use __get_user() to copy
sigset_t") introduced a regression in __get_user_sigset() for
powerpc/32. The bug was subsequently moved into
unsafe_get_user_sigset().

The bug is due to the copied 64 bit value being truncated to
32 bits while being assigned to dst->sig[0]

[...]

Applied to powerpc/fixes.

[1/1] powerpc/signal32: Fix sigset_t copy
      https://git.kernel.org/powerpc/c/5499802b2284331788a440585869590f1bd63f7f

cheers