diff options
Diffstat (limited to 'arch/x86/kernel/signal.c')
| -rw-r--r-- | arch/x86/kernel/signal.c | 461 |
1 files changed, 194 insertions, 267 deletions
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 4fd173cd8e5..2851d63c120 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -6,30 +6,36 @@ * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes * 2000-2002 x86-64 support by Andi Kleen */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/sched.h> #include <linux/mm.h> #include <linux/smp.h> #include <linux/kernel.h> -#include <linux/signal.h> #include <linux/errno.h> #include <linux/wait.h> -#include <linux/ptrace.h> #include <linux/tracehook.h> #include <linux/unistd.h> #include <linux/stddef.h> #include <linux/personality.h> #include <linux/uaccess.h> #include <linux/user-return-notifier.h> +#include <linux/uprobes.h> +#include <linux/context_tracking.h> #include <asm/processor.h> #include <asm/ucontext.h> #include <asm/i387.h> +#include <asm/fpu-internal.h> #include <asm/vdso.h> #include <asm/mce.h> +#include <asm/sighandling.h> #ifdef CONFIG_X86_64 #include <asm/proto.h> #include <asm/ia32_unistd.h> +#include <asm/sys_ia32.h> #endif /* CONFIG_X86_64 */ #include <asm/syscall.h> @@ -37,19 +43,6 @@ #include <asm/sigframe.h> -#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) - -#define __FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \ - X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \ - X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \ - X86_EFLAGS_CF) - -#ifdef CONFIG_X86_32 -# define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF) -#else -# define FIX_EFLAGS __FIX_EFLAGS -#endif - #define COPY(x) do { \ get_user_ex(regs->x, &sc->x); \ } while (0) @@ -68,9 +61,8 @@ regs->seg = GET_SEG(seg) | 3; \ } while (0) -static int -restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, - unsigned long *pax) +int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, + unsigned long *pax) { void __user *buf; unsigned int tmpflags; @@ -117,17 +109,17 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, regs->orig_ax = -1; /* disable syscall checks */ get_user_ex(buf, &sc->fpstate); - err |= restore_i387_xstate(buf); get_user_ex(*pax, &sc->ax); } get_user_catch(err); + err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32)); + return err; } -static int -setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, - struct pt_regs *regs, unsigned long mask) +int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, + struct pt_regs *regs, unsigned long mask) { int err = 0; @@ -159,7 +151,7 @@ setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, put_user_ex(regs->r15, &sc->r15); #endif /* CONFIG_X86_64 */ - put_user_ex(current->thread.trap_no, &sc->trapno); + put_user_ex(current->thread.trap_nr, &sc->trapno); put_user_ex(current->thread.error_code, &sc->err); put_user_ex(regs->ip, &sc->ip); #ifdef CONFIG_X86_32 @@ -210,35 +202,32 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, void __user **fpstate) { /* Default to using normal stack */ + unsigned long math_size = 0; unsigned long sp = regs->sp; + unsigned long buf_fx = 0; int onsigstack = on_sig_stack(sp); -#ifdef CONFIG_X86_64 /* redzone */ - sp -= 128; -#endif /* CONFIG_X86_64 */ + if (config_enabled(CONFIG_X86_64)) + sp -= 128; if (!onsigstack) { /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { if (current->sas_ss_size) sp = current->sas_ss_sp + current->sas_ss_size; - } else { -#ifdef CONFIG_X86_32 - /* This is the legacy signal stack switching. */ - if ((regs->ss & 0xffff) != __USER_DS && - !(ka->sa.sa_flags & SA_RESTORER) && - ka->sa.sa_restorer) + } else if (config_enabled(CONFIG_X86_32) && + (regs->ss & 0xffff) != __USER_DS && + !(ka->sa.sa_flags & SA_RESTORER) && + ka->sa.sa_restorer) { + /* This is the legacy signal stack switching. */ sp = (unsigned long) ka->sa.sa_restorer; -#endif /* CONFIG_X86_32 */ } } if (used_math()) { - sp -= sig_xstate_size; -#ifdef CONFIG_X86_64 - sp = round_down(sp, 64); -#endif /* CONFIG_X86_64 */ + sp = alloc_mathframe(sp, config_enabled(CONFIG_X86_32), + &buf_fx, &math_size); *fpstate = (void __user *)sp; } @@ -251,8 +240,9 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, if (onsigstack && !likely(on_sig_stack(sp))) return (void __user *)-1L; - /* save i387 state */ - if (used_math() && save_i387_xstate(*fpstate) < 0) + /* save i387 and extended state */ + if (used_math() && + save_xstate_sig(*fpstate, (void __user *)buf_fx, math_size) < 0) return (void __user *)-1L; return (void __user *)sp; @@ -282,7 +272,7 @@ static const struct { }; static int -__setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, +__setup_frame(int sig, struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) { struct sigframe __user *frame; @@ -290,7 +280,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, int err = 0; void __user *fpstate = NULL; - frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); + frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) return -EFAULT; @@ -308,11 +298,12 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, } if (current->mm->context.vdso) - restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn); + restorer = current->mm->context.vdso + + selected_vdso32->sym___kernel_sigreturn; else restorer = &frame->retcode; - if (ka->sa.sa_flags & SA_RESTORER) - restorer = ka->sa.sa_restorer; + if (ksig->ka.sa.sa_flags & SA_RESTORER) + restorer = ksig->ka.sa.sa_restorer; /* Set up to return from userspace. */ err |= __put_user(restorer, &frame->pretcode); @@ -331,7 +322,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, /* Set up registers for signal handler */ regs->sp = (unsigned long)frame; - regs->ip = (unsigned long)ka->sa.sa_handler; + regs->ip = (unsigned long)ksig->ka.sa.sa_handler; regs->ax = (unsigned long)sig; regs->dx = 0; regs->cx = 0; @@ -344,7 +335,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, return 0; } -static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, +static int __setup_rt_frame(int sig, struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) { struct rt_sigframe __user *frame; @@ -352,7 +343,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, int err = 0; void __user *fpstate = NULL; - frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); + frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) return -EFAULT; @@ -361,7 +352,6 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, put_user_ex(sig, &frame->sig); put_user_ex(&frame->info, &frame->pinfo); put_user_ex(&frame->uc, &frame->puc); - err |= copy_siginfo_to_user(&frame->info, info); /* Create the ucontext. */ if (cpu_has_xsave) @@ -369,18 +359,13 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, else put_user_ex(0, &frame->uc.uc_flags); put_user_ex(0, &frame->uc.uc_link); - put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); - put_user_ex(sas_ss_flags(regs->sp), - &frame->uc.uc_stack.ss_flags); - put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size); - err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, - regs, set->sig[0]); - err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + save_altstack_ex(&frame->uc.uc_stack, regs->sp); /* Set up to return from userspace. */ - restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); - if (ka->sa.sa_flags & SA_RESTORER) - restorer = ka->sa.sa_restorer; + restorer = current->mm->context.vdso + + selected_vdso32->sym___kernel_rt_sigreturn; + if (ksig->ka.sa.sa_flags & SA_RESTORER) + restorer = ksig->ka.sa.sa_restorer; put_user_ex(restorer, &frame->pretcode); /* @@ -392,13 +377,18 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, */ put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode); } put_user_catch(err); + + err |= copy_siginfo_to_user(&frame->info, &ksig->info); + err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, + regs, set->sig[0]); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); if (err) return -EFAULT; /* Set up registers for signal handler */ regs->sp = (unsigned long)frame; - regs->ip = (unsigned long)ka->sa.sa_handler; + regs->ip = (unsigned long)ksig->ka.sa.sa_handler; regs->ax = (unsigned long)sig; regs->dx = (unsigned long)&frame->info; regs->cx = (unsigned long)&frame->uc; @@ -411,21 +401,20 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, return 0; } #else /* !CONFIG_X86_32 */ -static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, +static int __setup_rt_frame(int sig, struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) { struct rt_sigframe __user *frame; void __user *fp = NULL; int err = 0; - struct task_struct *me = current; - frame = get_sigframe(ka, regs, sizeof(struct rt_sigframe), &fp); + frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp); if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) return -EFAULT; - if (ka->sa.sa_flags & SA_SIGINFO) { - if (copy_siginfo_to_user(&frame->info, info)) + if (ksig->ka.sa.sa_flags & SA_SIGINFO) { + if (copy_siginfo_to_user(&frame->info, &ksig->info)) return -EFAULT; } @@ -436,24 +425,22 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, else put_user_ex(0, &frame->uc.uc_flags); put_user_ex(0, &frame->uc.uc_link); - put_user_ex(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp); - put_user_ex(sas_ss_flags(regs->sp), - &frame->uc.uc_stack.ss_flags); - put_user_ex(me->sas_ss_size, &frame->uc.uc_stack.ss_size); - err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); - err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + save_altstack_ex(&frame->uc.uc_stack, regs->sp); /* Set up to return from userspace. If provided, use a stub already in userspace. */ /* x86-64 should always use SA_RESTORER. */ - if (ka->sa.sa_flags & SA_RESTORER) { - put_user_ex(ka->sa.sa_restorer, &frame->pretcode); + if (ksig->ka.sa.sa_flags & SA_RESTORER) { + put_user_ex(ksig->ka.sa.sa_restorer, &frame->pretcode); } else { /* could use a vstub here */ err |= -EFAULT; } } put_user_catch(err); + err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + if (err) return -EFAULT; @@ -466,7 +453,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, next argument after the signal number on the stack. */ regs->si = (unsigned long)&frame->info; regs->dx = (unsigned long)&frame->uc; - regs->ip = (unsigned long) ka->sa.sa_handler; + regs->ip = (unsigned long) ksig->ka.sa.sa_handler; regs->sp = (unsigned long)frame; @@ -478,86 +465,79 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, } #endif /* CONFIG_X86_32 */ -#ifdef CONFIG_X86_32 -/* - * Atomically swap in the new signal mask, and wait for a signal. - */ -asmlinkage int -sys_sigsuspend(int history0, int history1, old_sigset_t mask) +static int x32_setup_rt_frame(struct ksignal *ksig, + compat_sigset_t *set, + struct pt_regs *regs) { - mask &= _BLOCKABLE; - spin_lock_irq(¤t->sighand->siglock); - current->saved_sigmask = current->blocked; - siginitset(¤t->blocked, mask); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - current->state = TASK_INTERRUPTIBLE; - schedule(); - set_restore_sigmask(); - - return -ERESTARTNOHAND; -} +#ifdef CONFIG_X86_X32_ABI + struct rt_sigframe_x32 __user *frame; + void __user *restorer; + int err = 0; + void __user *fpstate = NULL; -asmlinkage int -sys_sigaction(int sig, const struct old_sigaction __user *act, - struct old_sigaction __user *oact) -{ - struct k_sigaction new_ka, old_ka; - int ret = 0; + frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); - if (act) { - old_sigset_t mask; + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + return -EFAULT; - if (!access_ok(VERIFY_READ, act, sizeof(*act))) + if (ksig->ka.sa.sa_flags & SA_SIGINFO) { + if (copy_siginfo_to_user32(&frame->info, &ksig->info)) return -EFAULT; + } + + put_user_try { + /* Create the ucontext. */ + if (cpu_has_xsave) + put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); + else + put_user_ex(0, &frame->uc.uc_flags); + put_user_ex(0, &frame->uc.uc_link); + compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp); + put_user_ex(0, &frame->uc.uc__pad0); - get_user_try { - get_user_ex(new_ka.sa.sa_handler, &act->sa_handler); - get_user_ex(new_ka.sa.sa_flags, &act->sa_flags); - get_user_ex(mask, &act->sa_mask); - get_user_ex(new_ka.sa.sa_restorer, &act->sa_restorer); - } get_user_catch(ret); + if (ksig->ka.sa.sa_flags & SA_RESTORER) { + restorer = ksig->ka.sa.sa_restorer; + } else { + /* could use a vstub here */ + restorer = NULL; + err |= -EFAULT; + } + put_user_ex(restorer, &frame->pretcode); + } put_user_catch(err); - if (ret) - return -EFAULT; - siginitset(&new_ka.sa.sa_mask, mask); - } + err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, + regs, set->sig[0]); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); - ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); + if (err) + return -EFAULT; - if (!ret && oact) { - if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact))) - return -EFAULT; + /* Set up registers for signal handler */ + regs->sp = (unsigned long) frame; + regs->ip = (unsigned long) ksig->ka.sa.sa_handler; - put_user_try { - put_user_ex(old_ka.sa.sa_handler, &oact->sa_handler); - put_user_ex(old_ka.sa.sa_flags, &oact->sa_flags); - put_user_ex(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); - put_user_ex(old_ka.sa.sa_restorer, &oact->sa_restorer); - } put_user_catch(ret); + /* We use the x32 calling convention here... */ + regs->di = ksig->sig; + regs->si = (unsigned long) &frame->info; + regs->dx = (unsigned long) &frame->uc; - if (ret) - return -EFAULT; - } + loadsegment(ds, __USER_DS); + loadsegment(es, __USER_DS); - return ret; -} -#endif /* CONFIG_X86_32 */ + regs->cs = __USER_CS; + regs->ss = __USER_DS; +#endif /* CONFIG_X86_X32_ABI */ -long -sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, - struct pt_regs *regs) -{ - return do_sigaltstack(uss, uoss, regs->sp); + return 0; } /* * Do a signal return; undo the signal stack. */ #ifdef CONFIG_X86_32 -unsigned long sys_sigreturn(struct pt_regs *regs) +asmlinkage unsigned long sys_sigreturn(void) { + struct pt_regs *regs = current_pt_regs(); struct sigframe __user *frame; unsigned long ax; sigset_t set; @@ -571,11 +551,7 @@ unsigned long sys_sigreturn(struct pt_regs *regs) sizeof(frame->extramask)))) goto badframe; - sigdelsetmask(&set, ~_BLOCKABLE); - spin_lock_irq(¤t->sighand->siglock); - current->blocked = set; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); + set_current_blocked(&set); if (restore_sigcontext(regs, &frame->sc, &ax)) goto badframe; @@ -588,8 +564,9 @@ badframe: } #endif /* CONFIG_X86_32 */ -long sys_rt_sigreturn(struct pt_regs *regs) +asmlinkage long sys_rt_sigreturn(void) { + struct pt_regs *regs = current_pt_regs(); struct rt_sigframe __user *frame; unsigned long ax; sigset_t set; @@ -600,16 +577,12 @@ long sys_rt_sigreturn(struct pt_regs *regs) if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) goto badframe; - sigdelsetmask(&set, ~_BLOCKABLE); - spin_lock_irq(¤t->sighand->siglock); - current->blocked = set; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); + set_current_blocked(&set); if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) goto badframe; - if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT) + if (restore_altstack(&frame->uc.uc_stack)) goto badframe; return ax; @@ -633,57 +606,30 @@ static int signr_convert(int sig) return sig; } -#ifdef CONFIG_X86_32 - -#define is_ia32 1 -#define ia32_setup_frame __setup_frame -#define ia32_setup_rt_frame __setup_rt_frame - -#else /* !CONFIG_X86_32 */ - -#ifdef CONFIG_IA32_EMULATION -#define is_ia32 test_thread_flag(TIF_IA32) -#else /* !CONFIG_IA32_EMULATION */ -#define is_ia32 0 -#endif /* CONFIG_IA32_EMULATION */ - -int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, - sigset_t *set, struct pt_regs *regs); -int ia32_setup_frame(int sig, struct k_sigaction *ka, - sigset_t *set, struct pt_regs *regs); - -#endif /* CONFIG_X86_32 */ - static int -setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, - sigset_t *set, struct pt_regs *regs) +setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) { - int usig = signr_convert(sig); - int ret; + int usig = signr_convert(ksig->sig); + sigset_t *set = sigmask_to_save(); + compat_sigset_t *cset = (compat_sigset_t *) set; /* Set up the stack frame */ - if (is_ia32) { - if (ka->sa.sa_flags & SA_SIGINFO) - ret = ia32_setup_rt_frame(usig, ka, info, set, regs); + if (is_ia32_frame()) { + if (ksig->ka.sa.sa_flags & SA_SIGINFO) + return ia32_setup_rt_frame(usig, ksig, cset, regs); else - ret = ia32_setup_frame(usig, ka, set, regs); - } else - ret = __setup_rt_frame(sig, ka, info, set, regs); - - if (ret) { - force_sigsegv(sig, current); - return -EFAULT; + return ia32_setup_frame(usig, ksig, cset, regs); + } else if (is_x32_frame()) { + return x32_setup_rt_frame(ksig, cset, regs); + } else { + return __setup_rt_frame(ksig->sig, ksig, set, regs); } - - return ret; } -static int -handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, - sigset_t *oldset, struct pt_regs *regs) +static void +handle_signal(struct ksignal *ksig, struct pt_regs *regs) { - int ret; - + bool failed; /* Are we from a system call? */ if (syscall_get_nr(current, regs) >= 0) { /* If so, check system call restarting.. */ @@ -694,7 +640,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, break; case -ERESTARTSYS: - if (!(ka->sa.sa_flags & SA_RESTART)) { + if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { regs->ax = -EINTR; break; } @@ -714,44 +660,23 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, likely(test_and_clear_thread_flag(TIF_FORCED_TF))) regs->flags &= ~X86_EFLAGS_TF; - ret = setup_rt_frame(sig, ka, info, oldset, regs); - - 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. - */ - regs->flags &= ~X86_EFLAGS_DF; - - /* - * Clear TF when entering the signal handler, but - * notify any tracer that was single-stepping it. - * The tracer may want to single-step inside the - * handler too. - */ - regs->flags &= ~X86_EFLAGS_TF; - - spin_lock_irq(¤t->sighand->siglock); - sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask); - if (!(ka->sa.sa_flags & SA_NODEFER)) - sigaddset(¤t->blocked, sig); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - tracehook_signal_handler(sig, info, ka, regs, - test_thread_flag(TIF_SINGLESTEP)); - - return 0; + failed = (setup_rt_frame(ksig, regs) < 0); + if (!failed) { + /* + * Clear the direction flag as per the ABI for function entry. + * + * Clear RF when entering the signal handler, because + * it might disable possible debug exception from the + * signal handler. + * + * Clear TF when entering the signal handler, but + * notify any tracer that was single-stepping it. + * The tracer may want to single-step inside the + * handler too. + */ + regs->flags &= ~(X86_EFLAGS_DF|X86_EFLAGS_RF|X86_EFLAGS_TF); + } + signal_setup_done(failed, ksig, test_thread_flag(TIF_SINGLESTEP)); } #ifdef CONFIG_X86_32 @@ -768,38 +693,11 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, */ static void do_signal(struct pt_regs *regs) { - struct k_sigaction ka; - siginfo_t info; - int signr; - sigset_t *oldset; - - /* - * We want the common case to go fast, which is why we may in certain - * cases get here from kernel mode. Just return without doing anything - * if so. - * X86_32: vm86 regs switched out by assembly code before reaching - * here, so testing against kernel CS suffices. - */ - if (!user_mode(regs)) - return; - - if (current_thread_info()->status & TS_RESTORE_SIGMASK) - oldset = ¤t->saved_sigmask; - else - oldset = ¤t->blocked; + struct ksignal ksig; - signr = get_signal_to_deliver(&info, &ka, regs, NULL); - if (signr > 0) { + if (get_signal(&ksig)) { /* Whee! Actually deliver the signal. */ - if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { - /* - * A signal was successfully delivered; the saved - * sigmask will have been stored in the signal frame, - * and will be restored by sigreturn, so we can simply - * clear the TS_RESTORE_SIGMASK flag. - */ - current_thread_info()->status &= ~TS_RESTORE_SIGMASK; - } + handle_signal(&ksig, regs); return; } @@ -825,25 +723,27 @@ static void do_signal(struct pt_regs *regs) * If there's no signal to deliver, we just put the saved sigmask * back. */ - if (current_thread_info()->status & TS_RESTORE_SIGMASK) { - current_thread_info()->status &= ~TS_RESTORE_SIGMASK; - sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); - } + restore_saved_sigmask(); } /* * notification of userspace execution resumption * - triggered by the TIF_WORK_MASK flags */ -void +__visible void do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) { + user_exit(); + #ifdef CONFIG_X86_MCE /* notify userspace of pending MCEs */ if (thread_info_flags & _TIF_MCE_NOTIFY) mce_notify_process(); #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ + if (thread_info_flags & _TIF_UPROBE) + uprobe_notify_resume(regs); + /* deal with pending signal delivery */ if (thread_info_flags & _TIF_SIGPENDING) do_signal(regs); @@ -851,15 +751,11 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) if (thread_info_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); - if (current->replacement_session_keyring) - key_replace_session_keyring(); } if (thread_info_flags & _TIF_USER_RETURN_NOTIFY) fire_user_return_notifiers(); -#ifdef CONFIG_X86_32 - clear_thread_flag(TIF_IRET); -#endif /* CONFIG_X86_32 */ + user_enter(); } void signal_fault(struct pt_regs *regs, void __user *frame, char *where) @@ -873,8 +769,39 @@ void signal_fault(struct pt_regs *regs, void __user *frame, char *where) me->comm, me->pid, where, frame, regs->ip, regs->sp, regs->orig_ax); print_vma_addr(" in ", regs->ip); - printk(KERN_CONT "\n"); + pr_cont("\n"); } force_sig(SIGSEGV, me); } + +#ifdef CONFIG_X86_X32_ABI +asmlinkage long sys32_x32_rt_sigreturn(void) +{ + struct pt_regs *regs = current_pt_regs(); + struct rt_sigframe_x32 __user *frame; + sigset_t set; + unsigned long ax; + + frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) + goto badframe; + + set_current_blocked(&set); + + if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) + goto badframe; + + if (compat_restore_altstack(&frame->uc.uc_stack)) + goto badframe; + + return ax; + +badframe: + signal_fault(regs, frame, "x32 rt_sigreturn"); + return 0; +} +#endif |
