diff options
Diffstat (limited to 'arch/x86/kernel/signal_64.c')
| -rw-r--r-- | arch/x86/kernel/signal_64.c | 84 |
1 files changed, 53 insertions, 31 deletions
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c index bf77d4789a2..a5c9627f4db 100644 --- a/arch/x86/kernel/signal_64.c +++ b/arch/x86/kernel/signal_64.c @@ -52,6 +52,16 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, return do_sigaltstack(uss, uoss, regs->sp); } +#define COPY(x) { \ + err |= __get_user(regs->x, &sc->x); \ +} + +#define COPY_SEG_STRICT(seg) { \ + unsigned short tmp; \ + err |= __get_user(tmp, &sc->seg); \ + regs->seg = tmp | 3; \ +} + /* * Do a signal return; undo the signal stack. */ @@ -59,13 +69,13 @@ static int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, unsigned long *pax) { + void __user *buf; + unsigned int tmpflags; unsigned int err = 0; /* Always make any pending restarted system calls return -EINTR */ current_thread_info()->restart_block.fn = do_no_restart_syscall; -#define COPY(x) (err |= __get_user(regs->x, &sc->x)) - COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); COPY(dx); COPY(cx); COPY(ip); COPY(r8); @@ -80,25 +90,14 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, /* Kernel saves and restores only the CS segment register on signals, * which is the bare minimum needed to allow mixed 32/64-bit code. * App's signal handler can save/restore other segments if needed. */ - { - unsigned cs; - err |= __get_user(cs, &sc->cs); - regs->cs = cs | 3; /* Force into user mode */ - } + COPY_SEG_STRICT(cs); - { - unsigned int tmpflags; - err |= __get_user(tmpflags, &sc->flags); - regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); - regs->orig_ax = -1; /* disable syscall checks */ - } - - { - void __user *buf; + err |= __get_user(tmpflags, &sc->flags); + regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); + regs->orig_ax = -1; /* disable syscall checks */ - err |= __get_user(buf, &sc->fpstate); - err |= restore_i387_xstate(buf); - } + err |= __get_user(buf, &sc->fpstate); + err |= restore_i387_xstate(buf); err |= __get_user(*pax, &sc->ax); return err; @@ -281,21 +280,32 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, /* * OK, we're invoking a handler */ +static int signr_convert(int sig) +{ + return sig; +} + +#ifdef CONFIG_IA32_EMULATION +#define is_ia32 test_thread_flag(TIF_IA32) +#else +#define is_ia32 0 +#endif + static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set, struct pt_regs *regs) { + int usig = signr_convert(sig); int ret; -#ifdef CONFIG_IA32_EMULATION - if (test_thread_flag(TIF_IA32)) { + /* Set up the stack frame */ + if (is_ia32) { if (ka->sa.sa_flags & SA_SIGINFO) - ret = ia32_setup_rt_frame(sig, ka, info, set, regs); + ret = ia32_setup_rt_frame(usig, ka, info, set, regs); else - ret = ia32_setup_frame(sig, ka, set, regs); + ret = ia32_setup_frame(usig, ka, set, regs); } else -#endif - ret = __setup_rt_frame(sig, ka, info, set, regs); + ret = __setup_rt_frame(sig, ka, info, set, regs); if (ret) { force_sigsegv(sig, current); @@ -346,12 +356,14 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, if (ret) return ret; +#ifdef CONFIG_X86_64 /* * This has nothing to do with segment registers, * despite the name. This magic affects uaccess.h * macros' behavior. Reset it to the normal setting. */ set_fs(USER_DS); +#endif /* * Clear the direction flag as per the ABI for function entry. @@ -410,7 +422,8 @@ static void do_signal(struct pt_regs *regs) signr = get_signal_to_deliver(&info, &ka, regs, NULL); if (signr > 0) { - /* Re-enable any watchpoints before delivering the + /* + * Re-enable any watchpoints before delivering the * signal to user space. The processor register will * have been cleared if the watchpoint triggered * inside the kernel. @@ -418,7 +431,7 @@ static void do_signal(struct pt_regs *regs) if (current->thread.debugreg7) set_debugreg(current->thread.debugreg7, 7); - /* Whee! Actually deliver the signal. */ + /* Whee! Actually deliver the signal. */ if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { /* * A signal was successfully delivered; the saved @@ -441,6 +454,7 @@ static void do_signal(struct pt_regs *regs) regs->ax = regs->orig_ax; regs->ip -= 2; break; + case -ERESTART_RESTARTBLOCK: regs->ax = NR_restart_syscall; regs->ip -= 2; @@ -458,14 +472,18 @@ static void do_signal(struct pt_regs *regs) } } -void do_notify_resume(struct pt_regs *regs, void *unused, - __u32 thread_info_flags) +/* + * notification of userspace execution resumption + * - triggered by the TIF_WORK_MASK flags + */ +void +do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) { -#ifdef CONFIG_X86_MCE +#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) /* notify userspace of pending MCEs */ if (thread_info_flags & _TIF_MCE_NOTIFY) mce_notify_user(); -#endif /* CONFIG_X86_MCE */ +#endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ /* deal with pending signal delivery */ if (thread_info_flags & _TIF_SIGPENDING) @@ -475,6 +493,10 @@ void do_notify_resume(struct pt_regs *regs, void *unused, clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); } + +#ifdef CONFIG_X86_32 + clear_thread_flag(TIF_IRET); +#endif /* CONFIG_X86_32 */ } void signal_fault(struct pt_regs *regs, void __user *frame, char *where) |