From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934567AbbLPRta (ORCPT ); Wed, 16 Dec 2015 12:49:30 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:50122 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966681AbbLPRkw (ORCPT ); Wed, 16 Dec 2015 12:40:52 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: "Dmitry V. Levin" , Elvira Khabirova , Thomas Gleixner , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 109/128] x86/signal: Fix restart_syscall number for x32 tasks Date: Wed, 16 Dec 2015 09:39:09 -0800 Message-Id: <1450287568-19808-110-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1450287568-19808-1-git-send-email-kamal@canonical.com> References: <1450287568-19808-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: "Dmitry V. Levin" commit 22eab1108781eff09961ae7001704f7bd8fb1dce upstream. When restarting a syscall with regs->ax == -ERESTART_RESTARTBLOCK, regs->ax is assigned to a restart_syscall number. For x32 tasks, this syscall number must have __X32_SYSCALL_BIT set, otherwise it will be an x86_64 syscall number instead of a valid x32 syscall number. This issue has been there since the introduction of x32. Reported-by: strace/tests/restart_syscall.test Reported-and-tested-by: Elvira Khabirova Signed-off-by: Dmitry V. Levin Cc: Elvira Khabirova Link: http://lkml.kernel.org/r/20151130215436.GA25996@altlinux.org Signed-off-by: Thomas Gleixner Signed-off-by: Kamal Mostafa --- arch/x86/kernel/signal.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index ed37a76..11577f5 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -684,12 +684,15 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) signal_setup_done(failed, ksig, test_thread_flag(TIF_SINGLESTEP)); } -#ifdef CONFIG_X86_32 -#define NR_restart_syscall __NR_restart_syscall -#else /* !CONFIG_X86_32 */ -#define NR_restart_syscall \ - test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall -#endif /* CONFIG_X86_32 */ +static inline unsigned long get_nr_restart_syscall(const struct pt_regs *regs) +{ +#if defined(CONFIG_X86_32) || !defined(CONFIG_X86_64) + return __NR_restart_syscall; +#else /* !CONFIG_X86_32 && CONFIG_X86_64 */ + return test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : + __NR_restart_syscall | (regs->orig_ax & __X32_SYSCALL_BIT); +#endif /* CONFIG_X86_32 || !CONFIG_X86_64 */ +} /* * Note that 'init' is a special process: it doesn't get signals it doesn't @@ -718,7 +721,7 @@ static void do_signal(struct pt_regs *regs) break; case -ERESTART_RESTARTBLOCK: - regs->ax = NR_restart_syscall; + regs->ax = get_nr_restart_syscall(regs); regs->ip -= 2; break; } -- 1.9.1