linux-stable/include/uapi
Florent Revest b3759b8705 mm: make PR_MDWE_REFUSE_EXEC_GAIN an unsigned long
commit 0da668333f upstream.

Defining a prctl flag as an int is a footgun because on a 64 bit machine
and with a variadic implementation of prctl (like in musl and glibc), when
used directly as a prctl argument, it can get casted to long with garbage
upper bits which would result in unexpected behaviors.

This patch changes the constant to an unsigned long to eliminate that
possibilities.  This does not break UAPI.

I think that a stable backport would be "nice to have": to reduce the
chances that users build binaries that could end up with garbage bits in
their MDWE prctl arguments.  We are not aware of anyone having yet
encountered this corner case with MDWE prctls but a backport would reduce
the likelihood it happens, since this sort of issues has happened with
other prctls.  But If this is perceived as a backporting burden, I suppose
we could also live without a stable backport.

Link: https://lkml.kernel.org/r/20230828150858.393570-5-revest@chromium.org
Fixes: b507808ebc ("mm: implement memory-deny-write-execute as a prctl")
Signed-off-by: Florent Revest <revest@chromium.org>
Suggested-by: Alexey Izbyshev <izbyshev@ispras.ru>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ayush Jain <ayush.jain3@amd.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Szabolcs Nagy <Szabolcs.Nagy@arm.com>
Cc: Topi Miettinen <toiwoton@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:15:08 +00:00
..
asm-generic
drm
linux mm: make PR_MDWE_REFUSE_EXEC_GAIN an unsigned long 2023-11-28 17:15:08 +00:00
misc
mtd
rdma
scsi
sound
video
xen xen/evtchn: Introduce new IOCTL to bind static evtchn 2023-07-26 08:42:34 +02:00
Kbuild