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 kNYWdAf9 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With CONFIG_TMPFS_POSIX_ACL, > this lets an unprivileged owner make a non-executable memfd executable, > bypassing vm.memfd_noexec=2. > > simple_set_acl() updates i_mode directly, bypassing the seal check in > shmem_setattr(). Add shmem_set_acl() to check the resulting mode. Share > the F_SEAL_EXEC check with shmem_setattr() using memfd_check_seals_mode() > in include/linux/memfd.h. > > Fix generated by an LLM and sent by Chris Mason in private. > > Fixes: 6fd7353829ca ("mm/memfd: add F_SEAL_EXEC") > Cc: stable@vger.kernel.org > Signed-off-by: Chris Mason > [ david: use common helper; simplify description ] > Signed-off-by: David Hildenbrand (Arm) > --- > include/linux/memfd.h | 9 +++++++++ > mm/shmem.c | 35 ++++++++++++++++++++++++++++++----- > 2 files changed, 39 insertions(+), 5 deletions(-) > The changes make sense to me. Acked-by: Zi Yan Best Regards, Yan, Zi