From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:36720 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031593AbeGAQi2 (ORCPT ); Sun, 1 Jul 2018 12:38:28 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shakeel Butt , Ram Pai , Thiago Jung Bauermann , Michael Ellerman Subject: [PATCH 4.17 045/220] powerpc/pkeys: Detach execute_only key on !PROT_EXEC Date: Sun, 1 Jul 2018 18:21:09 +0200 Message-Id: <20180701160910.206851258@linuxfoundation.org> In-Reply-To: <20180701160908.272447118@linuxfoundation.org> References: <20180701160908.272447118@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ram Pai commit eabdb8ca8690eedd461e61ea7780595fbbae8132 upstream. 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. Fixes: 5586cf61e108 ("powerpc: introduce execute-only pkey") Cc: stable@vger.kernel.org # v4.16+ Reported-by: Shakeel Butt Signed-off-by: Ram Pai Reviewed-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/mm/pkeys.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/powerpc/mm/pkeys.c +++ b/arch/powerpc/mm/pkeys.c @@ -383,9 +383,9 @@ int __arch_override_mprotect_pkey(struct { /* * 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; /*