From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752034AbeFALZV (ORCPT ); Fri, 1 Jun 2018 07:25:21 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:50334 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751968AbeFALZO (ORCPT ); Fri, 1 Jun 2018 07:25:14 -0400 From: Mark Rutland To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, will.deacon@arm.com, catalin.marinas@arm.com Cc: Mark Rutland , Al Viro , Christoph Hellwig , Dave Martin , Dominik Brodowski Subject: [PATCHv2 13/19] kernel: add ksys_personality() Date: Fri, 1 Jun 2018 12:24:35 +0100 Message-Id: <20180601112441.37810-14-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180601112441.37810-1-mark.rutland@arm.com> References: <20180601112441.37810-1-mark.rutland@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Using this helper allows us to avoid the in-kernel call to the sys_personality() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_personality(). Since ksys_personality is trivial, it is implemented directly in , as we do for ksys_close() and friends. This helper is necessary to enable conversion of arm64's syscall handling to use pt_regs wrappers. Signed-off-by: Mark Rutland Cc: Al Viro Cc: Christoph Hellwig Cc: Dave Martin Cc: Dominik Brodowski --- include/linux/syscalls.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 70fcda1a9049..652e166deb64 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -79,6 +79,7 @@ union bpf_attr; #include #include #include +#include #include #ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER @@ -1268,4 +1269,14 @@ static inline long ksys_truncate(const char __user *pathname, loff_t length) return do_sys_truncate(pathname, length); } +static inline unsigned int ksys_personality(unsigned int personality) +{ + unsigned int old = current->personality; + + if (personality != 0xffffffff) + set_personality(personality); + + return old; +} + #endif -- 2.11.0