This is a note to let you know that I've just added the patch titled x86/signal: Fix restart_syscall number for x32 tasks to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-signal-fix-restart_syscall-number-for-x32-tasks.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 22eab1108781eff09961ae7001704f7bd8fb1dce Mon Sep 17 00:00:00 2001 From: "Dmitry V. Levin" <ldv@xxxxxxxxxxxx> Date: Tue, 1 Dec 2015 00:54:36 +0300 Subject: x86/signal: Fix restart_syscall number for x32 tasks From: "Dmitry V. Levin" <ldv@xxxxxxxxxxxx> 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 <lineprinter0@xxxxxxxxx> Signed-off-by: Dmitry V. Levin <ldv@xxxxxxxxxxxx> Cc: Elvira Khabirova <lineprinter0@xxxxxxxxx> Link: http://lkml.kernel.org/r/20151130215436.GA25996@xxxxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/signal.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -667,12 +667,15 @@ handle_signal(struct ksignal *ksig, stru 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 @@ -701,7 +704,7 @@ static void do_signal(struct pt_regs *re break; case -ERESTART_RESTARTBLOCK: - regs->ax = NR_restart_syscall; + regs->ax = get_nr_restart_syscall(regs); regs->ip -= 2; break; } Patches currently in stable-queue which might be from ldv@xxxxxxxxxxxx are queue-4.1/x86-signal-fix-restart_syscall-number-for-x32-tasks.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html