| /* |
| * arch/ppc/kernel/signal.c |
| * |
| * PowerPC version |
| * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) |
| * |
| * Derived from "arch/i386/kernel/signal.c" |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| #include <linux/sched.h> |
| #include <linux/mm.h> |
| #include <linux/smp.h> |
| #include <linux/smp_lock.h> |
| #include <linux/kernel.h> |
| #include <linux/signal.h> |
| #include <linux/errno.h> |
| #include <linux/wait.h> |
| #include <linux/ptrace.h> |
| #include <linux/unistd.h> |
| #include <linux/stddef.h> |
| #include <linux/elf.h> |
| #include <linux/tty.h> |
| #include <linux/binfmts.h> |
| #include <linux/suspend.h> |
| #include <asm/ucontext.h> |
| #include <asm/uaccess.h> |
| #include <asm/pgtable.h> |
| #include <asm/cacheflush.h> |
| |
| #undef DEBUG_SIG |
| |
| #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) |
| |
| extern void sigreturn_exit(struct pt_regs *); |
| |
| #define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs)) |
| |
| int do_signal(sigset_t *oldset, struct pt_regs *regs); |
| |
| /* |
| * Atomically swap in the new signal mask, and wait for a signal. |
| */ |
| int |
| sys_sigsuspend(old_sigset_t mask, int p2, int p3, int p4, int p6, int p7, |
| struct pt_regs *regs) |
| { |
| sigset_t saveset; |
| |
| mask &= _BLOCKABLE; |
| spin_lock_irq(¤t->sighand->siglock); |
| saveset = current->blocked; |
| siginitset(¤t->blocked, mask); |
| recalc_sigpending(); |
| spin_unlock_irq(¤t->sighand->siglock); |
| |
| regs->result = -EINTR; |
| regs->gpr[3] = EINTR; |
| regs->ccr |= 0x10000000; |
| while (1) { |
| current->state = TASK_INTERRUPTIBLE; |
| schedule(); |
| if (do_signal(&saveset, regs)) |
| sigreturn_exit(regs); |
| } |
| } |
| |
| int |
| sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, int p3, int p4, |
| int p6, int p7, struct pt_regs *regs) |
| { |
| sigset_t saveset, newset; |
| |
| /* XXX: Don't preclude handling different sized sigset_t's. */ |
| if (sigsetsize != sizeof(sigset_t)) |
| return -EINVAL; |
| |
| if (copy_from_user(&newset, unewset, sizeof(newset))) |
| return -EFAULT; |
| sigdelsetmask(&newset, ~_BLOCKABLE); |
| |
| spin_lock_irq(¤t->sighand->siglock); |
| saveset = current->blocked; |
| current->blocked = newset; |
| recalc_sigpending(); |
| spin_unlock_irq(¤t->sighand->siglock); |
| |
| regs->result = -EINTR; |
| regs->gpr[3] = EINTR; |
| regs->ccr |= 0x10000000; |
| while (1) { |
| current->state = TASK_INTERRUPTIBLE; |
| schedule(); |
| if (do_signal(&saveset, regs)) |
| sigreturn_exit(regs); |
| } |
| } |
| |
| |
| int |
| sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, int r5, |
| int r6, int r7, int r8, struct pt_regs *regs) |
| { |
| return do_sigaltstack(uss, uoss, regs->gpr[1]); |
| } |
| |
| 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; |
| |
| if (act) { |
| old_sigset_t mask; |
| if (!access_ok(VERIFY_READ, act, sizeof(*act)) || |
| __get_user(new_ka.sa.sa_handler, &act->sa_handler) || |
| __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) |
| return -EFAULT; |
| __get_user(new_ka.sa.sa_flags, &act->sa_flags); |
| __get_user(mask, &act->sa_mask); |
| siginitset(&new_ka.sa.sa_mask, mask); |
| } |
| |
| ret = do_sigaction(sig, (act? &new_ka: NULL), (oact? &old_ka: NULL)); |
| |
| if (!ret && oact) { |
| if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || |
| __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || |
| __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) |
| return -EFAULT; |
| __put_user(old_ka.sa.sa_flags, &oact->sa_flags); |
| __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * When we have signals to deliver, we set up on the |
| * user stack, going down from the original stack pointer: |
| * a sigregs struct |
| * a sigcontext struct |
| * a gap of __SIGNAL_FRAMESIZE bytes |
| * |
| * Each of these things must be a multiple of 16 bytes in size. |
| * |
| */ |
| struct sigregs { |
| struct mcontext mctx; /* all the register values */ |
| /* Programs using the rs6000/xcoff abi can save up to 19 gp regs |
| and 18 fp regs below sp before decrementing it. */ |
| int abigap[56]; |
| }; |
| |
| /* We use the mc_pad field for the signal return trampoline. */ |
| #define tramp mc_pad |
| |
| /* |
| * When we have rt signals to deliver, we set up on the |
| * user stack, going down from the original stack pointer: |
| * one rt_sigframe struct (siginfo + ucontext + ABI gap) |
| * a gap of __SIGNAL_FRAMESIZE+16 bytes |
| * (the +16 is to get the siginfo and ucontext in the same |
| * positions as in older kernels). |
| * |
| * Each of these things must be a multiple of 16 bytes in size. |
| * |
| */ |
| struct rt_sigframe |
| { |
| struct siginfo info; |
| struct ucontext uc; |
| /* Programs using the rs6000/xcoff abi can save up to 19 gp regs |
| and 18 fp regs below sp before decrementing it. */ |
| int abigap[56]; |
| }; |
| |
| /* |
| * Save the current user registers on the user stack. |
| * We only save the altivec/spe registers if the process has used |
| * altivec/spe instructions at some point. |
| */ |
| static int |
| save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, int sigret) |
| { |
| /* save general and floating-point registers */ |
| CHECK_FULL_REGS(regs); |
| preempt_disable(); |
| if (regs->msr & MSR_FP) |
| giveup_fpu(current); |
| #ifdef CONFIG_ALTIVEC |
| if (current->thread.used_vr && (regs->msr & MSR_VEC)) |
| giveup_altivec(current); |
| #endif /* CONFIG_ALTIVEC */ |
| #ifdef CONFIG_SPE |
| if (current->thread.used_spe && (regs->msr & MSR_SPE)) |
| giveup_spe(current); |
| #endif /* CONFIG_ALTIVEC */ |
| preempt_enable(); |
| |
| if (__copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE) |
| || __copy_to_user(&frame->mc_fregs, current->thread.fpr, |
| ELF_NFPREG * sizeof(double))) |
| return 1; |
| |
| current->thread.fpscr = 0; /* turn off all fp exceptions */ |
| |
| #ifdef CONFIG_ALTIVEC |
| /* save altivec registers */ |
| if (current->thread.used_vr) { |
| if (__copy_to_user(&frame->mc_vregs, current->thread.vr, |
| ELF_NVRREG * sizeof(vector128))) |
| return 1; |
| /* set MSR_VEC in the saved MSR value to indicate that |
| frame->mc_vregs contains valid data */ |
| if (__put_user(regs->msr | MSR_VEC, &frame->mc_gregs[PT_MSR])) |
| return 1; |
| } |
| /* else assert((regs->msr & MSR_VEC) == 0) */ |
| |
| /* We always copy to/from vrsave, it's 0 if we don't have or don't |
| * use altivec. Since VSCR only contains 32 bits saved in the least |
| * significant bits of a vector, we "cheat" and stuff VRSAVE in the |
| * most significant bits of that same vector. --BenH |
| */ |
| if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32])) |
| return 1; |
| #endif /* CONFIG_ALTIVEC */ |
| |
| #ifdef CONFIG_SPE |
| /* save spe registers */ |
| if (current->thread.used_spe) { |
| if (__copy_to_user(&frame->mc_vregs, current->thread.evr, |
| ELF_NEVRREG * sizeof(u32))) |
| return 1; |
| /* set MSR_SPE in the saved MSR value to indicate that |
| frame->mc_vregs contains valid data */ |
| if (__put_user(regs->msr | MSR_SPE, &frame->mc_gregs[PT_MSR])) |
| return 1; |
| } |
| /* else assert((regs->msr & MSR_SPE) == 0) */ |
| |
| /* We always copy to/from spefscr */ |
| if (__put_user(current->thread.spefscr, (u32 *)&frame->mc_vregs + ELF_NEVRREG)) |
| return 1; |
| #endif /* CONFIG_SPE */ |
| |
| if (sigret) { |
| /* Set up the sigreturn trampoline: li r0,sigret; sc */ |
| if (__put_user(0x38000000UL + sigret, &frame->tramp[0]) |
| || __put_user(0x44000002UL, &frame->tramp[1])) |
| return 1; |
| flush_icache_range((unsigned long) &frame->tramp[0], |
| (unsigned long) &frame->tramp[2]); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Restore the current user register values from the user stack, |
| * (except for MSR). |
| */ |
| static int |
| restore_user_regs(struct pt_regs *regs, struct mcontext __user *sr, int sig) |
| { |
| unsigned long save_r2 = 0; |
| #if defined(CONFIG_ALTIVEC) || defined(CONFIG_SPE) |
| unsigned long msr; |
| #endif |
| |
| /* backup/restore the TLS as we don't want it to be modified */ |
| if (!sig) |
| save_r2 = regs->gpr[2]; |
| /* copy up to but not including MSR */ |
| if (__copy_from_user(regs, &sr->mc_gregs, PT_MSR * sizeof(elf_greg_t))) |
| return 1; |
| /* copy from orig_r3 (the word after the MSR) up to the end */ |
| if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3], |
| GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t))) |
| return 1; |
| if (!sig) |
| regs->gpr[2] = save_r2; |
| |
| /* force the process to reload the FP registers from |
| current->thread when it next does FP instructions */ |
| regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1); |
| if (__copy_from_user(current->thread.fpr, &sr->mc_fregs, |
| sizeof(sr->mc_fregs))) |
| return 1; |
| |
| #ifdef CONFIG_ALTIVEC |
| /* force the process to reload the altivec registers from |
| current->thread when it next does altivec instructions */ |
| regs->msr &= ~MSR_VEC; |
| if (!__get_user(msr, &sr->mc_gregs[PT_MSR]) && (msr & MSR_VEC) != 0) { |
| /* restore altivec registers from the stack */ |
| if (__copy_from_user(current->thread.vr, &sr->mc_vregs, |
| sizeof(sr->mc_vregs))) |
| return 1; |
| } else if (current->thread.used_vr) |
| memset(¤t->thread.vr, 0, ELF_NVRREG * sizeof(vector128)); |
| |
| /* Always get VRSAVE back */ |
| if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32])) |
| return 1; |
| #endif /* CONFIG_ALTIVEC */ |
| |
| #ifdef CONFIG_SPE |
| /* force the process to reload the spe registers from |
| current->thread when it next does spe instructions */ |
| regs->msr &= ~MSR_SPE; |
| if (!__get_user(msr, &sr->mc_gregs[PT_MSR]) && (msr & MSR_SPE) != 0) { |
| /* restore spe registers from the stack */ |
| if (__copy_from_user(current->thread.evr, &sr->mc_vregs, |
| ELF_NEVRREG * sizeof(u32))) |
| return 1; |
| } else if (current->thread.used_spe) |
| memset(¤t->thread.evr, 0, ELF_NEVRREG * sizeof(u32)); |
| |
| /* Always get SPEFSCR back */ |
| if (__get_user(current->thread.spefscr, (u32 *)&sr->mc_vregs + ELF_NEVRREG)) |
| return 1; |
| #endif /* CONFIG_SPE */ |
| |
| #ifndef CONFIG_SMP |
| preempt_disable(); |
| if (last_task_used_math == current) |
| last_task_used_math = NULL; |
| if (last_task_used_altivec == current) |
| last_task_used_altivec = NULL; |
| if (last_task_used_spe == current) |
| last_task_used_spe = NULL; |
| preempt_enable(); |
| #endif |
| return 0; |
| } |
| |
| /* |
| * Restore the user process's signal mask |
| */ |
| static void |
| restore_sigmask(sigset_t *set) |
| { |
| sigdelsetmask(set, ~_BLOCKABLE); |
| spin_lock_irq(¤t->sighand->siglock); |
| current->blocked = *set; |
| recalc_sigpending(); |
| spin_unlock_irq(¤t->sighand->siglock); |
| } |
| |
| /* |
| * Set up a signal frame for a "real-time" signal handler |
| * (one which gets siginfo). |
| */ |
| static void |
| handle_rt_signal(unsigned long sig, struct k_sigaction *ka, |
| siginfo_t *info, sigset_t *oldset, struct pt_regs * regs, |
| unsigned long newsp) |
| { |
| struct rt_sigframe __user *rt_sf; |
| struct mcontext __user *frame; |
| unsigned long origsp = newsp; |
| |
| /* Set up Signal Frame */ |
| /* Put a Real Time Context onto stack */ |
| newsp -= sizeof(*rt_sf); |
| rt_sf = (struct rt_sigframe __user *) newsp; |
| |
| /* create a stack frame for the caller of the handler */ |
| newsp -= __SIGNAL_FRAMESIZE + 16; |
| |
| if (!access_ok(VERIFY_WRITE, (void __user *) newsp, origsp - newsp)) |
| goto badframe; |
| |
| /* Put the siginfo & fill in most of the ucontext */ |
| if (copy_siginfo_to_user(&rt_sf->info, info) |
| || __put_user(0, &rt_sf->uc.uc_flags) |
| || __put_user(0, &rt_sf->uc.uc_link) |
| || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp) |
| || __put_user(sas_ss_flags(regs->gpr[1]), |
| &rt_sf->uc.uc_stack.ss_flags) |
| || __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size) |
| || __put_user(&rt_sf->uc.uc_mcontext, &rt_sf->uc.uc_regs) |
| || __copy_to_user(&rt_sf->uc.uc_sigmask, oldset, sizeof(*oldset))) |
| goto badframe; |
| |
| /* Save user registers on the stack */ |
| frame = &rt_sf->uc.uc_mcontext; |
| if (save_user_regs(regs, frame, __NR_rt_sigreturn)) |
| goto badframe; |
| |
| if (put_user(regs->gpr[1], (unsigned long __user *)newsp)) |
| goto badframe; |
| regs->gpr[1] = newsp; |
| regs->gpr[3] = sig; |
| regs->gpr[4] = (unsigned long) &rt_sf->info; |
| regs->gpr[5] = (unsigned long) &rt_sf->uc; |
| regs->gpr[6] = (unsigned long) rt_sf; |
| regs->nip = (unsigned long) ka->sa.sa_handler; |
| regs->link = (unsigned long) frame->tramp; |
| regs->trap = 0; |
| |
| return; |
| |
| badframe: |
| #ifdef DEBUG_SIG |
| printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n", |
| regs, frame, newsp); |
| #endif |
| force_sigsegv(sig, current); |
| } |
| |
| static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig) |
| { |
| sigset_t set; |
| struct mcontext __user *mcp; |
| |
| if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(set)) |
| || __get_user(mcp, &ucp->uc_regs)) |
| return -EFAULT; |
| restore_sigmask(&set); |
| if (restore_user_regs(regs, mcp, sig)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| int sys_swapcontext(struct ucontext __user *old_ctx, |
| struct ucontext __user *new_ctx, |
| int ctx_size, int r6, int r7, int r8, struct pt_regs *regs) |
| { |
| unsigned char tmp; |
| |
| /* Context size is for future use. Right now, we only make sure |
| * we are passed something we understand |
| */ |
| if (ctx_size < sizeof(struct ucontext)) |
| return -EINVAL; |
| |
| if (old_ctx != NULL) { |
| if (!access_ok(VERIFY_WRITE, old_ctx, sizeof(*old_ctx)) |
| || save_user_regs(regs, &old_ctx->uc_mcontext, 0) |
| || __copy_to_user(&old_ctx->uc_sigmask, |
| ¤t->blocked, sizeof(sigset_t)) |
| || __put_user(&old_ctx->uc_mcontext, &old_ctx->uc_regs)) |
| return -EFAULT; |
| } |
| if (new_ctx == NULL) |
| return 0; |
| if (!access_ok(VERIFY_READ, new_ctx, sizeof(*new_ctx)) |
| || __get_user(tmp, (u8 __user *) new_ctx) |
| || __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1)) |
| return -EFAULT; |
| |
| /* |
| * If we get a fault copying the context into the kernel's |
| * image of the user's registers, we can't just return -EFAULT |
| * because the user's registers will be corrupted. For instance |
| * the NIP value may have been updated but not some of the |
| * other registers. Given that we have done the access_ok |
| * and successfully read the first and last bytes of the region |
| * above, this should only happen in an out-of-memory situation |
| * or if another thread unmaps the region containing the context. |
| * We kill the task with a SIGSEGV in this situation. |
| */ |
| if (do_setcontext(new_ctx, regs, 0)) |
| do_exit(SIGSEGV); |
| sigreturn_exit(regs); |
| /* doesn't actually return back to here */ |
| return 0; |
| } |
| |
| int sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8, |
| struct pt_regs *regs) |
| { |
| struct rt_sigframe __user *rt_sf; |
| |
| /* Always make any pending restarted system calls return -EINTR */ |
| current_thread_info()->restart_block.fn = do_no_restart_syscall; |
| |
| rt_sf = (struct rt_sigframe __user *) |
| (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16); |
| if (!access_ok(VERIFY_READ, rt_sf, sizeof(struct rt_sigframe))) |
| goto bad; |
| if (do_setcontext(&rt_sf->uc, regs, 1)) |
| goto bad; |
| |
| /* |
| * It's not clear whether or why it is desirable to save the |
| * sigaltstack setting on signal delivery and restore it on |
| * signal return. But other architectures do this and we have |
| * always done it up until now so it is probably better not to |
| * change it. -- paulus |
| */ |
| do_sigaltstack(&rt_sf->uc.uc_stack, NULL, regs->gpr[1]); |
| |
| sigreturn_exit(regs); /* doesn't return here */ |
| return 0; |
| |
| bad: |
| force_sig(SIGSEGV, current); |
| return 0; |
| } |
| |
| int sys_debug_setcontext(struct ucontext __user *ctx, |
| int ndbg, struct sig_dbg_op __user *dbg, |
| int r6, int r7, int r8, |
| struct pt_regs *regs) |
| { |
| struct sig_dbg_op op; |
| int i; |
| unsigned long new_msr = regs->msr; |
| #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) |
| unsigned long new_dbcr0 = current->thread.dbcr0; |
| #endif |
| |
| for (i=0; i<ndbg; i++) { |
| if (__copy_from_user(&op, dbg, sizeof(op))) |
| return -EFAULT; |
| switch (op.dbg_type) { |
| case SIG_DBG_SINGLE_STEPPING: |
| #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) |
| if (op.dbg_value) { |
| new_msr |= MSR_DE; |
| new_dbcr0 |= (DBCR0_IDM | DBCR0_IC); |
| } else { |
| new_msr &= ~MSR_DE; |
| new_dbcr0 &= ~(DBCR0_IDM | DBCR0_IC); |
| } |
| #else |
| if (op.dbg_value) |
| new_msr |= MSR_SE; |
| else |
| new_msr &= ~MSR_SE; |
| #endif |
| break; |
| case SIG_DBG_BRANCH_TRACING: |
| #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) |
| return -EINVAL; |
| #else |
| if (op.dbg_value) |
| new_msr |= MSR_BE; |
| else |
| new_msr &= ~MSR_BE; |
| #endif |
| break; |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| /* We wait until here to actually install the values in the |
| registers so if we fail in the above loop, it will not |
| affect the contents of these registers. After this point, |
| failure is a problem, anyway, and it's very unlikely unless |
| the user is really doing something wrong. */ |
| regs->msr = new_msr; |
| #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) |
| current->thread.dbcr0 = new_dbcr0; |
| #endif |
| |
| /* |
| * If we get a fault copying the context into the kernel's |
| * image of the user's registers, we can't just return -EFAULT |
| * because the user's registers will be corrupted. For instance |
| * the NIP value may have been updated but not some of the |
| * other registers. Given that we have done the access_ok |
| * and successfully read the first and last bytes of the region |
| * above, this should only happen in an out-of-memory situation |
| * or if another thread unmaps the region containing the context. |
| * We kill the task with a SIGSEGV in this situation. |
| */ |
| if (do_setcontext(ctx, regs, 1)) { |
| force_sig(SIGSEGV, current); |
| goto out; |
| } |
| |
| /* |
| * It's not clear whether or why it is desirable to save the |
| * sigaltstack setting on signal delivery and restore it on |
| * signal return. But other architectures do this and we have |
| * always done it up until now so it is probably better not to |
| * change it. -- paulus |
| */ |
| do_sigaltstack(&ctx->uc_stack, NULL, regs->gpr[1]); |
| |
| sigreturn_exit(regs); |
| /* doesn't actually return back to here */ |
| |
| out: |
| return 0; |
| } |
| |
| /* |
| * OK, we're invoking a handler |
| */ |
| static void |
| handle_signal(unsigned long sig, struct k_sigaction *ka, |
| siginfo_t *info, sigset_t *oldset, struct pt_regs * regs, |
| unsigned long newsp) |
| { |
| struct sigcontext __user *sc; |
| struct sigregs __user *frame; |
| unsigned long origsp = newsp; |
| |
| /* Set up Signal Frame */ |
| newsp -= sizeof(struct sigregs); |
| frame = (struct sigregs __user *) newsp; |
| |
| /* Put a sigcontext on the stack */ |
| newsp -= sizeof(*sc); |
| sc = (struct sigcontext __user *) newsp; |
| |
| /* create a stack frame for the caller of the handler */ |
| newsp -= __SIGNAL_FRAMESIZE; |
| |
| if (!access_ok(VERIFY_WRITE, (void __user *) newsp, origsp - newsp)) |
| goto badframe; |
| |
| #if _NSIG != 64 |
| #error "Please adjust handle_signal()" |
| #endif |
| if (__put_user((unsigned long) ka->sa.sa_handler, &sc->handler) |
| || __put_user(oldset->sig[0], &sc->oldmask) |
| || __put_user(oldset->sig[1], &sc->_unused[3]) |
| || __put_user((struct pt_regs __user *)frame, &sc->regs) |
| || __put_user(sig, &sc->signal)) |
| goto badframe; |
| |
| if (save_user_regs(regs, &frame->mctx, __NR_sigreturn)) |
| goto badframe; |
| |
| if (put_user(regs->gpr[1], (unsigned long __user *)newsp)) |
| goto badframe; |
| regs->gpr[1] = newsp; |
| regs->gpr[3] = sig; |
| regs->gpr[4] = (unsigned long) sc; |
| regs->nip = (unsigned long) ka->sa.sa_handler; |
| regs->link = (unsigned long) frame->mctx.tramp; |
| regs->trap = 0; |
| |
| return; |
| |
| badframe: |
| #ifdef DEBUG_SIG |
| printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n", |
| regs, frame, newsp); |
| #endif |
| force_sigsegv(sig, current); |
| } |
| |
| /* |
| * Do a signal return; undo the signal stack. |
| */ |
| int sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8, |
| struct pt_regs *regs) |
| { |
| struct sigcontext __user *sc; |
| struct sigcontext sigctx; |
| struct mcontext __user *sr; |
| sigset_t set; |
| |
| /* Always make any pending restarted system calls return -EINTR */ |
| current_thread_info()->restart_block.fn = do_no_restart_syscall; |
| |
| sc = (struct sigcontext __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE); |
| if (copy_from_user(&sigctx, sc, sizeof(sigctx))) |
| goto badframe; |
| |
| set.sig[0] = sigctx.oldmask; |
| set.sig[1] = sigctx._unused[3]; |
| restore_sigmask(&set); |
| |
| sr = (struct mcontext __user *) sigctx.regs; |
| if (!access_ok(VERIFY_READ, sr, sizeof(*sr)) |
| || restore_user_regs(regs, sr, 1)) |
| goto badframe; |
| |
| sigreturn_exit(regs); /* doesn't return */ |
| return 0; |
| |
| badframe: |
| force_sig(SIGSEGV, current); |
| return 0; |
| } |
| |
| /* |
| * Note that 'init' is a special process: it doesn't get signals it doesn't |
| * want to handle. Thus you cannot kill init even with a SIGKILL even by |
| * mistake. |
| */ |
| int do_signal(sigset_t *oldset, struct pt_regs *regs) |
| { |
| siginfo_t info; |
| struct k_sigaction ka; |
| unsigned long frame, newsp; |
| int signr, ret; |
| |
| if (try_to_freeze()) { |
| signr = 0; |
| if (!signal_pending(current)) |
| goto no_signal; |
| } |
| |
| if (!oldset) |
| oldset = ¤t->blocked; |
| |
| newsp = frame = 0; |
| |
| signr = get_signal_to_deliver(&info, &ka, regs, NULL); |
| no_signal: |
| if (TRAP(regs) == 0x0C00 /* System Call! */ |
| && regs->ccr & 0x10000000 /* error signalled */ |
| && ((ret = regs->gpr[3]) == ERESTARTSYS |
| || ret == ERESTARTNOHAND || ret == ERESTARTNOINTR |
| || ret == ERESTART_RESTARTBLOCK)) { |
| |
| if (signr > 0 |
| && (ret == ERESTARTNOHAND || ret == ERESTART_RESTARTBLOCK |
| || (ret == ERESTARTSYS |
| && !(ka.sa.sa_flags & SA_RESTART)))) { |
| /* make the system call return an EINTR error */ |
| regs->result = -EINTR; |
| regs->gpr[3] = EINTR; |
| /* note that the cr0.SO bit is already set */ |
| } else { |
| regs->nip -= 4; /* Back up & retry system call */ |
| regs->result = 0; |
| regs->trap = 0; |
| if (ret == ERESTART_RESTARTBLOCK) |
| regs->gpr[0] = __NR_restart_syscall; |
| else |
| regs->gpr[3] = regs->orig_gpr3; |
| } |
| } |
| |
| if (signr == 0) |
| return 0; /* no signals delivered */ |
| |
| if ((ka.sa.sa_flags & SA_ONSTACK) && current->sas_ss_size |
| && !on_sig_stack(regs->gpr[1])) |
| newsp = current->sas_ss_sp + current->sas_ss_size; |
| else |
| newsp = regs->gpr[1]; |
| newsp &= ~0xfUL; |
| |
| /* Whee! Actually deliver the signal. */ |
| if (ka.sa.sa_flags & SA_SIGINFO) |
| handle_rt_signal(signr, &ka, &info, oldset, regs, newsp); |
| else |
| handle_signal(signr, &ka, &info, oldset, regs, newsp); |
| |
| if (!(ka.sa.sa_flags & SA_NODEFER)) { |
| spin_lock_irq(¤t->sighand->siglock); |
| sigorsets(¤t->blocked,¤t->blocked,&ka.sa.sa_mask); |
| sigaddset(¤t->blocked, signr); |
| recalc_sigpending(); |
| spin_unlock_irq(¤t->sighand->siglock); |
| } |
| |
| return 1; |
| } |
| |