diff options
Diffstat (limited to 'arch/x86/kernel/signal.c')
| -rw-r--r-- | arch/x86/kernel/signal.c | 219 |
1 files changed, 6 insertions, 213 deletions
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 0511e050d24a..962cfd835c90 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -92,10 +92,6 @@ static void force_valid_ss(struct pt_regs *regs) ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA_EXPDOWN)) regs->ss = __USER_DS; } -# define CONTEXT_COPY_SIZE offsetof(struct sigcontext, reserved1) -#else -# define CONTEXT_COPY_SIZE sizeof(struct sigcontext) -#endif static bool restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, @@ -106,16 +102,9 @@ static bool restore_sigcontext(struct pt_regs *regs, /* Always make any pending restarted system calls return -EINTR */ current->restart_block.fn = do_no_restart_syscall; - if (copy_from_user(&sc, usc, CONTEXT_COPY_SIZE)) + if (copy_from_user(&sc, usc, offsetof(struct sigcontext, reserved1))) return false; -#ifdef CONFIG_X86_32 - loadsegment(gs, sc.gs); - regs->fs = sc.fs; - regs->es = sc.es; - regs->ds = sc.ds; -#endif /* CONFIG_X86_32 */ - regs->bx = sc.bx; regs->cx = sc.cx; regs->dx = sc.dx; @@ -125,8 +114,6 @@ static bool restore_sigcontext(struct pt_regs *regs, regs->ax = sc.ax; regs->sp = sc.sp; regs->ip = sc.ip; - -#ifdef CONFIG_X86_64 regs->r8 = sc.r8; regs->r9 = sc.r9; regs->r10 = sc.r10; @@ -135,7 +122,6 @@ static bool restore_sigcontext(struct pt_regs *regs, regs->r13 = sc.r13; regs->r14 = sc.r14; regs->r15 = sc.r15; -#endif /* CONFIG_X86_64 */ /* Get CS/SS and force CPL3 */ regs->cs = sc.cs | 0x03; @@ -145,33 +131,20 @@ static bool restore_sigcontext(struct pt_regs *regs, /* disable syscall checks */ regs->orig_ax = -1; -#ifdef CONFIG_X86_64 /* * Fix up SS if needed for the benefit of old DOSEMU and * CRIU. */ if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && user_64bit_mode(regs))) force_valid_ss(regs); -#endif - return fpu__restore_sig((void __user *)sc.fpstate, - IS_ENABLED(CONFIG_X86_32)); + return fpu__restore_sig((void __user *)sc.fpstate, 0); } static __always_inline int __unsafe_setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, struct pt_regs *regs, unsigned long mask) { -#ifdef CONFIG_X86_32 - unsigned int gs; - savesegment(gs, gs); - - unsafe_put_user(gs, (unsigned int __user *)&sc->gs, Efault); - unsafe_put_user(regs->fs, (unsigned int __user *)&sc->fs, Efault); - unsafe_put_user(regs->es, (unsigned int __user *)&sc->es, Efault); - unsafe_put_user(regs->ds, (unsigned int __user *)&sc->ds, Efault); -#endif /* CONFIG_X86_32 */ - unsafe_put_user(regs->di, &sc->di, Efault); unsafe_put_user(regs->si, &sc->si, Efault); unsafe_put_user(regs->bp, &sc->bp, Efault); @@ -180,7 +153,6 @@ __unsafe_setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, unsafe_put_user(regs->dx, &sc->dx, Efault); unsafe_put_user(regs->cx, &sc->cx, Efault); unsafe_put_user(regs->ax, &sc->ax, Efault); -#ifdef CONFIG_X86_64 unsafe_put_user(regs->r8, &sc->r8, Efault); unsafe_put_user(regs->r9, &sc->r9, Efault); unsafe_put_user(regs->r10, &sc->r10, Efault); @@ -189,23 +161,15 @@ __unsafe_setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, unsafe_put_user(regs->r13, &sc->r13, Efault); unsafe_put_user(regs->r14, &sc->r14, Efault); unsafe_put_user(regs->r15, &sc->r15, Efault); -#endif /* CONFIG_X86_64 */ unsafe_put_user(current->thread.trap_nr, &sc->trapno, Efault); unsafe_put_user(current->thread.error_code, &sc->err, Efault); unsafe_put_user(regs->ip, &sc->ip, Efault); -#ifdef CONFIG_X86_32 - unsafe_put_user(regs->cs, (unsigned int __user *)&sc->cs, Efault); - unsafe_put_user(regs->flags, &sc->flags, Efault); - unsafe_put_user(regs->sp, &sc->sp_at_signal, Efault); - unsafe_put_user(regs->ss, (unsigned int __user *)&sc->ss, Efault); -#else /* !CONFIG_X86_32 */ unsafe_put_user(regs->flags, &sc->flags, Efault); unsafe_put_user(regs->cs, &sc->cs, Efault); unsafe_put_user(0, &sc->gs, Efault); unsafe_put_user(0, &sc->fs, Efault); unsafe_put_user(regs->ss, &sc->ss, Efault); -#endif /* CONFIG_X86_32 */ unsafe_put_user(fpstate, (unsigned long __user *)&sc->fpstate, Efault); @@ -228,6 +192,8 @@ do { \ (__u64 __user *)&(frame)->uc.uc_sigmask, \ label) +#endif /* CONFIG_X86_64 */ + /* * Set up a signal frame. */ @@ -313,148 +279,7 @@ get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size, return (void __user *)sp; } -#ifdef CONFIG_X86_32 -static const struct { - u16 poplmovl; - u32 val; - u16 int80; -} __attribute__((packed)) retcode = { - 0xb858, /* popl %eax; movl $..., %eax */ - __NR_sigreturn, - 0x80cd, /* int $0x80 */ -}; - -static const struct { - u8 movl; - u32 val; - u16 int80; - u8 pad; -} __attribute__((packed)) rt_retcode = { - 0xb8, /* movl $..., %eax */ - __NR_rt_sigreturn, - 0x80cd, /* int $0x80 */ - 0 -}; - -int ia32_setup_frame(struct ksignal *ksig, struct pt_regs *regs) -{ - sigset_t *set = sigmask_to_save(); - struct sigframe __user *frame; - void __user *restorer; - void __user *fp = NULL; - - frame = get_sigframe(ksig, regs, sizeof(*frame), &fp); - - if (!user_access_begin(frame, sizeof(*frame))) - return -EFAULT; - - unsafe_put_user(ksig->sig, &frame->sig, Efault); - unsafe_put_sigcontext(&frame->sc, fp, regs, set, Efault); - unsafe_put_user(set->sig[1], &frame->extramask[0], Efault); - if (current->mm->context.vdso) - restorer = current->mm->context.vdso + - vdso_image_32.sym___kernel_sigreturn; - else - restorer = &frame->retcode; - if (ksig->ka.sa.sa_flags & SA_RESTORER) - restorer = ksig->ka.sa.sa_restorer; - - /* Set up to return from userspace. */ - unsafe_put_user(restorer, &frame->pretcode, Efault); - - /* - * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 - * - * WE DO NOT USE IT ANY MORE! It's only left here for historical - * reasons and because gdb uses it as a signature to notice - * signal handler stack frames. - */ - unsafe_put_user(*((u64 *)&retcode), (u64 *)frame->retcode, Efault); - user_access_end(); - - /* Set up registers for signal handler */ - regs->sp = (unsigned long)frame; - regs->ip = (unsigned long)ksig->ka.sa.sa_handler; - regs->ax = (unsigned long)ksig->sig; - regs->dx = 0; - regs->cx = 0; - - regs->ds = __USER_DS; - regs->es = __USER_DS; - regs->ss = __USER_DS; - regs->cs = __USER_CS; - - return 0; - -Efault: - user_access_end(); - return -EFAULT; -} - -int ia32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) -{ - sigset_t *set = sigmask_to_save(); - struct rt_sigframe __user *frame; - void __user *restorer; - void __user *fp = NULL; - - frame = get_sigframe(ksig, regs, sizeof(*frame), &fp); - - if (!user_access_begin(frame, sizeof(*frame))) - return -EFAULT; - - unsafe_put_user(ksig->sig, &frame->sig, Efault); - unsafe_put_user(&frame->info, &frame->pinfo, Efault); - unsafe_put_user(&frame->uc, &frame->puc, Efault); - - /* Create the ucontext. */ - if (static_cpu_has(X86_FEATURE_XSAVE)) - unsafe_put_user(UC_FP_XSTATE, &frame->uc.uc_flags, Efault); - else - unsafe_put_user(0, &frame->uc.uc_flags, Efault); - unsafe_put_user(0, &frame->uc.uc_link, Efault); - unsafe_save_altstack(&frame->uc.uc_stack, regs->sp, Efault); - - /* Set up to return from userspace. */ - restorer = current->mm->context.vdso + - vdso_image_32.sym___kernel_rt_sigreturn; - if (ksig->ka.sa.sa_flags & SA_RESTORER) - restorer = ksig->ka.sa.sa_restorer; - unsafe_put_user(restorer, &frame->pretcode, Efault); - - /* - * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 - * - * WE DO NOT USE IT ANY MORE! It's only left here for historical - * reasons and because gdb uses it as a signature to notice - * signal handler stack frames. - */ - unsafe_put_user(*((u64 *)&rt_retcode), (u64 *)frame->retcode, Efault); - unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault); - unsafe_put_sigmask(set, frame, Efault); - user_access_end(); - - if (copy_siginfo_to_user(&frame->info, &ksig->info)) - return -EFAULT; - - /* Set up registers for signal handler */ - regs->sp = (unsigned long)frame; - regs->ip = (unsigned long)ksig->ka.sa.sa_handler; - regs->ax = (unsigned long)ksig->sig; - regs->dx = (unsigned long)&frame->info; - regs->cx = (unsigned long)&frame->uc; - - regs->ds = __USER_DS; - regs->es = __USER_DS; - regs->ss = __USER_DS; - regs->cs = __USER_CS; - - return 0; -Efault: - user_access_end(); - return -EFAULT; -} -#else /* !CONFIG_X86_32 */ +#ifdef CONFIG_X86_64 static unsigned long frame_uc_flags(struct pt_regs *regs) { unsigned long flags; @@ -545,7 +370,6 @@ Efault: user_access_end(); return -EFAULT; } -#endif /* CONFIG_X86_32 */ #ifdef CONFIG_X86_X32_ABI static int x32_copy_siginfo_to_user(struct compat_siginfo __user *to, @@ -631,38 +455,6 @@ Efault: /* * Do a signal return; undo the signal stack. */ -#ifdef CONFIG_X86_32 -SYSCALL_DEFINE0(sigreturn) -{ - struct pt_regs *regs = current_pt_regs(); - struct sigframe __user *frame; - sigset_t set; - - frame = (struct sigframe __user *)(regs->sp - 8); - - if (!access_ok(frame, sizeof(*frame))) - goto badframe; - if (__get_user(set.sig[0], &frame->sc.oldmask) || - __get_user(set.sig[1], &frame->extramask[0])) - goto badframe; - - set_current_blocked(&set); - - /* - * x86_32 has no uc_flags bits relevant to restore_sigcontext. - * Save a few cycles by skipping the __get_user. - */ - if (!restore_sigcontext(regs, &frame->sc, 0)) - goto badframe; - return regs->ax; - -badframe: - signal_fault(regs, frame, "sigreturn"); - - return 0; -} -#endif /* CONFIG_X86_32 */ - SYSCALL_DEFINE0(rt_sigreturn) { struct pt_regs *regs = current_pt_regs(); @@ -692,6 +484,7 @@ badframe: signal_fault(regs, frame, "rt_sigreturn"); return 0; } +#endif /* CONFIG_X86_64 */ /* * There are four different struct types for signal frame: sigframe_ia32, |