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
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asm	asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch	2023-06-22 17:04:36 +02:00
asm-generic	tools headers UAPI: Sync files changed by new cachestat syscall with the kernel sources	2023-07-11 11:41:15 -03:00
drm	tools headers UAPI: Sync drm/i915_drm.h with the kernel sources	2023-07-11 11:41:15 -03:00
linux	mm: make PR_MDWE_REFUSE_EXEC_GAIN an unsigned long	2023-11-28 17:15:08 +00:00
sound	tools include UAPI: Sync the sound/asound.h copy with the kernel sources	2023-07-14 10:33:50 -03:00