hugetlbfs: enforce F_SEAL_EXEC in setattr

F_SEAL_EXEC is enforced by shmem_setattr(), but hugetlbfs_setattr() does
not check it. As a result, fchmod() can change the execute bits of a
sealed hugetlbfs memfd.

Use memfd_check_seals_mode() in hugetlbfs_setattr() to reject changes
to execute bits when F_SEAL_EXEC is set.

This also fixes the memfd_test hugetlbfs SEAL-EXEC subtest, where
fchmod() incorrectly succeeded after applying F_SEAL_EXEC.

Fixes: 6fd7353829ca ("mm/memfd: add F_SEAL_EXEC")
Cc: stable@vger.kernel.org
Signed-off-by: Eva Kurchatova <eva.kurchatova@virtuozzo.com>
Link: https://patch.msgid.link/20260629180247.2343229-1-eva.kurchatova@virtuozzo.com
Acked-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Acked-by: Zi Yan <ziy@nvidia.com>
Tested-by: Gregory Price (Meta) <gourry@gourry.net>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
[ david: use common helper; fixup Fixes:; check only regular files ]
Acked-by: Oscar Salvador <osalvador@suse.de>
Link: https://patch.msgid.link/20261029-fixes_shmem-v4-5-392fc715d8f6@kernel.org
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>

0 files changed, 0 insertions, 0 deletions