Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755094AbbK3Vyj (ORCPT ); Mon, 30 Nov 2015 16:54:39 -0500 Received: from pegasus3.altlinux.org ([194.107.17.103]:33775 "EHLO pegasus3.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752625AbbK3Vyi (ORCPT ); Mon, 30 Nov 2015 16:54:38 -0500 Date: Tue, 1 Dec 2015 00:54:36 +0300 From: "Dmitry V. Levin" To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: Elvira Khabirova , x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] x86/signal: fix restart_syscall number for x32 tasks Message-ID: <20151130215436.GA25996@altlinux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2035 Lines: 55 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. Reported-by: strace/tests/restart_syscall.test Reported-and-tested-by: Elvira Khabirova Signed-off-by: Dmitry V. Levin Cc: stable@vger.kernel.org --- 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 b7ffb7c..cb6282c 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -690,12 +690,15 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) signal_setup_done(failed, ksig, stepping); } -#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 @@ -724,7 +727,7 @@ 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; } -- ldv -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/