Disassociate the exec_key from a VMA if the VMA permission is not PROT_EXEC anymore. Otherwise the exec_only key continues to be associated with the vma, causing unexpected behavior.
The problem was reported on x86 by Shakeel Butt, which is also applicable on powerpc. cc: Shakeel Butt <shake...@google.com> Reported-by: Shakeel Butt <shake...@google.com> Fixes 5586cf6 ("powerpc: introduce execute-only pkey") Signed-off-by: Ram Pai <linux...@us.ibm.com> --- arch/powerpc/mm/pkeys.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c index e81d59e..fdeb9f5 100644 --- a/arch/powerpc/mm/pkeys.c +++ b/arch/powerpc/mm/pkeys.c @@ -425,9 +425,9 @@ int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot, { /* * If the currently associated pkey is execute-only, but the requested - * protection requires read or write, move it back to the default pkey. + * protection is not execute-only, move it back to the default pkey. */ - if (vma_is_pkey_exec_only(vma) && (prot & (PROT_READ | PROT_WRITE))) + if (vma_is_pkey_exec_only(vma) && (prot != PROT_EXEC)) return 0; /* -- 1.7.1