/* $Id: signal32.c,v 1.4 2000/03/15 22:46:55 kanoj Exp $ * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 1991, 1992 Linus Torvalds * Copyright (C) 1994 - 1999 Ralf Baechle * Copyright (C) 1999 Silicon Graphics, Inc. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DEBUG_SIG 0 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) extern asmlinkage int sys_wait4(pid_t pid, unsigned long *stat_addr, int options, unsigned long *ru); extern asmlinkage int do_signal32(sigset_t *oldset, struct pt_regs *regs); extern asmlinkage int save_fp_context(struct sigcontext *sc); extern asmlinkage int restore_fp_context(struct sigcontext *sc); /* 32-bit compatibility types */ #define _NSIG32_BPW 32 #define _NSIG32_WORDS (_NSIG / _NSIG32_BPW) typedef struct { unsigned int sig[_NSIG32_WORDS]; } sigset32_t; typedef unsigned int __sighandler32_t; typedef void (*vfptr_t)(void); struct sigaction32 { unsigned int sa_flags; __sighandler32_t sa_handler; sigset32_t sa_mask; unsigned int sa_restorer; int sa_resv[1]; /* reserved */ }; /* IRIX compatible stack_t */ typedef struct sigaltstack32 { void *ss_sp; size_t ss_size; int ss_flags; } stack32_t; static inline int store_fp_context(struct sigcontext *sc) { unsigned int fcr0; int err = 0; err |= __copy_to_user(&sc->sc_fpregs[0], ¤t->thread.fpu.hard.fp_regs[0], NUM_FPU_REGS * sizeof(unsigned long)); err |= __copy_to_user(&sc->sc_fpc_csr, ¤t->thread.fpu.hard.control, sizeof(unsigned int)); __asm__ __volatile__("cfc1 %0, $0\n\t" : "=r" (fcr0)); err |= __copy_to_user(&sc->sc_fpc_eir, &fcr0, sizeof(unsigned int)); return err; } static inline int refill_fp_context(struct sigcontext *sc) { int err = 0; if (verify_area(VERIFY_READ, sc, sizeof(*sc))) return -EFAULT; err |= __copy_from_user(¤t->thread.fpu.hard.fp_regs[0], &sc->sc_fpregs[0], NUM_FPU_REGS * sizeof(unsigned long)); err |= __copy_from_user(¤t->thread.fpu.hard.control, &sc->sc_fpc_csr, sizeof(unsigned int)); return err; } /* * Atomically swap in the new signal mask, and wait for a signal. */ asmlinkage inline int sys32_sigsuspend(abi64_no_regargs, struct pt_regs regs) { sigset_t *uset, saveset, newset; save_static(®s); printk("%s called.\n", __FUNCTION__); uset = (sigset_t *) regs.regs[4]; if (copy_from_user(&newset, uset, sizeof(sigset_t))) return -EFAULT; sigdelsetmask(&newset, ~_BLOCKABLE); spin_lock_irq(¤t->sigmask_lock); saveset = current->blocked; current->blocked = newset; recalc_sigpending(current); spin_unlock_irq(¤t->sigmask_lock); regs.regs[2] = EINTR; regs.regs[7] = 1; while (1) { current->state = TASK_INTERRUPTIBLE; schedule(); if (do_signal32(&saveset, ®s)) return -EINTR; } } asmlinkage int sys32_rt_sigsuspend(abi64_no_regargs, struct pt_regs regs) { sigset_t *unewset, saveset, newset; size_t sigsetsize; save_static(®s); printk("%s called.\n", __FUNCTION__); /* XXX Don't preclude handling different sized sigset_t's. */ sigsetsize = regs.regs[5]; if (sigsetsize != sizeof(sigset_t)) return -EINVAL; unewset = (sigset_t *) regs.regs[4]; if (copy_from_user(&newset, unewset, sizeof(newset))) return -EFAULT; sigdelsetmask(&newset, ~_BLOCKABLE); spin_lock_irq(¤t->sigmask_lock); saveset = current->blocked; current->blocked = newset; recalc_sigpending(current); spin_unlock_irq(¤t->sigmask_lock); regs.regs[2] = EINTR; regs.regs[7] = 1; while (1) { current->state = TASK_INTERRUPTIBLE; schedule(); if (do_signal32(&saveset, ®s)) return -EINTR; } } asmlinkage int sys32_sigaction(int sig, const struct sigaction32 *act, struct sigaction32 *oact) { struct k_sigaction new_ka, old_ka; int ret; int err = 0; if (act) { old_sigset_t mask; if (!access_ok(VERIFY_READ, act, sizeof(*act))) return -EFAULT; err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler); err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags); err |= __get_user(mask, &act->sa_mask.sig[0]); err |= __get_user(new_ka.sa.sa_restorer, &act->sa_restorer); if (err) return -EFAULT; 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))) return -EFAULT; err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags); err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler); err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig); err |= __put_user(0, &oact->sa_mask.sig[1]); err |= __put_user(0, &oact->sa_mask.sig[2]); err |= __put_user(0, &oact->sa_mask.sig[3]); err |= __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer); if (err) return -EFAULT; } return ret; } asmlinkage int sys32_sigaltstack(abi64_no_regargs, struct pt_regs regs) { const stack_t *uss = (const stack_t *) regs.regs[4]; stack_t *uoss = (stack_t *) regs.regs[5]; unsigned long usp = regs.regs[29]; printk("%s called.\n", __FUNCTION__); return do_sigaltstack(uss, uoss, usp); } static asmlinkage int restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc) { int owned_fp; int err = 0; err |= __get_user(regs->cp0_epc, &sc->sc_pc); err |= __get_user(regs->hi, &sc->sc_mdhi); err |= __get_user(regs->lo, &sc->sc_mdlo); #define restore_gp_reg(i) do { \ err |= __get_user(regs->regs[i], &sc->sc_regs[i]); \ } while(0) restore_gp_reg( 1); restore_gp_reg( 2); restore_gp_reg( 3); restore_gp_reg( 4); restore_gp_reg( 5); restore_gp_reg( 6); restore_gp_reg( 7); restore_gp_reg( 8); restore_gp_reg( 9); restore_gp_reg(10); restore_gp_reg(11); restore_gp_reg(12); restore_gp_reg(13); restore_gp_reg(14); restore_gp_reg(15); restore_gp_reg(16); restore_gp_reg(17); restore_gp_reg(18); restore_gp_reg(19); restore_gp_reg(20); restore_gp_reg(21); restore_gp_reg(22); restore_gp_reg(23); restore_gp_reg(24); restore_gp_reg(25); restore_gp_reg(26); restore_gp_reg(27); restore_gp_reg(28); restore_gp_reg(29); restore_gp_reg(30); restore_gp_reg(31); #undef restore_gp_reg err |= __get_user(owned_fp, &sc->sc_ownedfp); if (owned_fp) { if (current == last_task_used_math) { last_task_used_math = 0; regs->cp0_status &= ~ST0_CU1; } current->used_math = 1; err |= refill_fp_context(sc); } return err; } struct sigframe { u32 sf_ass[4]; /* argument save space for o32 */ u32 sf_code[2]; /* signal trampoline */ struct sigcontext sf_sc; sigset_t sf_mask; }; struct rt_sigframe { u32 rs_ass[4]; /* argument save space for o32 */ u32 rs_code[2]; /* signal trampoline */ struct siginfo rs_info; struct ucontext rs_uc; }; asmlinkage void sys32_sigreturn(abi64_no_regargs, struct pt_regs regs) { struct sigframe *frame; sigset_t blocked; #if DEBUG_MIPS64 printk("%s called.\n", __FUNCTION__); #endif frame = (struct sigframe *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) goto badframe; if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked))) goto badframe; sigdelsetmask(&blocked, ~_BLOCKABLE); spin_lock_irq(¤t->sigmask_lock); current->blocked = blocked; recalc_sigpending(current); spin_unlock_irq(¤t->sigmask_lock); if (restore_sigcontext(®s, &frame->sf_sc)) goto badframe; /* * Don't let your children do this ... */ __asm__ __volatile__( "move\t$29, %0\n\t" "j\tret_from_sys_call" :/* no outputs */ :"r" (®s)); /* Unreached */ badframe: force_sig(SIGSEGV, current); } asmlinkage void sys32_rt_sigreturn(abi64_no_regargs, struct pt_regs regs) { struct rt_sigframe *frame; sigset_t set; stack_t st; printk("%s called.\n", __FUNCTION__); frame = (struct rt_sigframe *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) goto badframe; if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set))) goto badframe; sigdelsetmask(&set, ~_BLOCKABLE); spin_lock_irq(¤t->sigmask_lock); current->blocked = set; recalc_sigpending(current); spin_unlock_irq(¤t->sigmask_lock); if (restore_sigcontext(®s, &frame->rs_uc.uc_mcontext)) goto badframe; if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st))) goto badframe; /* It is more difficult to avoid calling this function than to call it and ignore errors. */ do_sigaltstack(&st, NULL, regs.regs[29]); /* * Don't let your children do this ... */ __asm__ __volatile__( "move\t$29, %0\n\t" "j\tret_from_sys_call" :/* no outputs */ :"r" (®s)); /* Unreached */ badframe: force_sig(SIGSEGV, current); } static int inline setup_sigcontext(struct pt_regs *regs, struct sigcontext *sc) { int err = 0; err |= __put_user(regs->cp0_epc, &sc->sc_pc); #define save_gp_reg(i) { \ err |= __put_user(regs->regs[i], &sc->sc_regs[i]); \ } while(0) __put_user(0, &sc->sc_regs[0]); save_gp_reg(1); save_gp_reg(2); save_gp_reg(3); save_gp_reg(4); save_gp_reg(5); save_gp_reg(6); save_gp_reg(7); save_gp_reg(8); save_gp_reg(9); save_gp_reg(10); save_gp_reg(11); save_gp_reg(12); save_gp_reg(13); save_gp_reg(14); save_gp_reg(15); save_gp_reg(16); save_gp_reg(17); save_gp_reg(18); save_gp_reg(19); save_gp_reg(20); save_gp_reg(21); save_gp_reg(22); save_gp_reg(23); save_gp_reg(24); save_gp_reg(25); save_gp_reg(26); save_gp_reg(27); save_gp_reg(28); save_gp_reg(29); save_gp_reg(30); save_gp_reg(31); #undef save_gp_reg err |= __put_user(regs->hi, &sc->sc_mdhi); err |= __put_user(regs->lo, &sc->sc_mdlo); err |= __put_user(regs->cp0_cause, &sc->sc_cause); err |= __put_user(regs->cp0_badvaddr, &sc->sc_badvaddr); if (current->used_math) { /* fp is active. */ if (current == last_task_used_math) { lazy_fpu_switch(current, 0); last_task_used_math = NULL; regs->cp0_status &= ~ST0_CU1; } err |= __put_user(1, &sc->sc_ownedfp); err |= store_fp_context(sc); current->used_math = 0; } else { err |= __put_user(0, &sc->sc_ownedfp); } err |= __put_user(regs->cp0_status, &sc->sc_status); return err; } /* * Determine which stack to use.. */ static inline void * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) { unsigned long sp; /* Default to using normal stack */ sp = regs->regs[29]; /* This is the X/Open sanctioned signal stack switching. */ if ((ka->sa.sa_flags & SA_ONSTACK) && ! on_sig_stack(sp)) sp = current->sas_ss_sp + current->sas_ss_size; return (void *)((sp - frame_size) & ALMASK); } static void inline setup_frame(struct k_sigaction * ka, struct pt_regs *regs, int signr, sigset_t *set) { struct sigframe *frame; int err = 0; frame = get_sigframe(ka, regs, sizeof(*frame)); if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) goto give_sigsegv; /* Set up to return from userspace. If provided, use a stub already in userspace. */ if (ka->sa.sa_flags & SA_RESTORER) regs->regs[31] = (unsigned long) ka->sa.sa_restorer; else { /* * Set up the return code ... * * li v0, __NR_Linux32_sigreturn * syscall */ err |= __put_user(0x24020000 + __NR_Linux32_sigreturn, frame->sf_code + 0); err |= __put_user(0x0000000c , frame->sf_code + 1); flush_cache_sigtramp((unsigned long) frame->sf_code); } err |= setup_sigcontext(regs, &frame->sf_sc); err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set)); if (err) goto give_sigsegv; /* * Arguments to signal handler: * * a0 = signal number * a1 = 0 (should be cause) * a2 = pointer to struct sigcontext * * $25 and c0_epc point to the signal handler, $29 points to the * struct sigframe. */ regs->regs[ 4] = signr; regs->regs[ 5] = 0; regs->regs[ 6] = (unsigned long) &frame->sf_sc; regs->regs[29] = (unsigned long) frame; regs->regs[31] = (unsigned long) frame->sf_code; regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler; #if DEBUG_SIG printk("SIG deliver (%s:%d): sp=0x%p pc=0x%p ra=0x%p\n", current->comm, current->pid, frame, regs->cp0_epc, frame->code); #endif return; give_sigsegv: if (signr == SIGSEGV) ka->sa.sa_handler = SIG_DFL; force_sig(SIGSEGV, current); } static void inline setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info) { struct rt_sigframe *frame; int err = 0; frame = get_sigframe(ka, regs, sizeof(*frame)); if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) goto give_sigsegv; /* Set up to return from userspace. If provided, use a stub already in userspace. */ if (ka->sa.sa_flags & SA_RESTORER) regs->regs[31] = (unsigned long) ka->sa.sa_restorer; else { /* * Set up the return code ... * * li v0, __NR_Linux32_sigreturn * syscall */ err |= __put_user(0x24020000 + __NR_Linux32_sigreturn, frame->rs_code + 0); err |= __put_user(0x0000000c , frame->rs_code + 1); flush_cache_sigtramp((unsigned long) frame->rs_code); } /* Create siginfo. */ err |= __copy_to_user(&frame->rs_info, info, sizeof(*info)); /* Create the ucontext. */ err |= __put_user(0, &frame->rs_uc.uc_flags); err |= __put_user(0, &frame->rs_uc.uc_link); err |= __put_user((void *)current->sas_ss_sp, &frame->rs_uc.uc_stack.ss_sp); err |= __put_user(sas_ss_flags(regs->regs[29]), &frame->rs_uc.uc_stack.ss_flags); err |= __put_user(current->sas_ss_size, &frame->rs_uc.uc_stack.ss_size); err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set)); if (err) goto give_sigsegv; /* * Arguments to signal handler: * * a0 = signal number * a1 = 0 (should be cause) * a2 = pointer to ucontext * * $25 and c0_epc point to the signal handler, $29 points to * the struct rt_sigframe. */ regs->regs[ 4] = signr; regs->regs[ 5] = (unsigned long) &frame->rs_info; regs->regs[ 6] = (unsigned long) &frame->rs_uc; regs->regs[29] = (unsigned long) frame; regs->regs[31] = (unsigned long) frame->rs_code; regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler; #if DEBUG_SIG printk("SIG deliver (%s:%d): sp=0x%p pc=0x%p ra=0x%p\n", current->comm, current->pid, frame, regs->cp0_epc, frame->code); #endif return; give_sigsegv: if (signr == SIGSEGV) ka->sa.sa_handler = SIG_DFL; force_sig(SIGSEGV, current); } static inline void handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *oldset, struct pt_regs * regs) { if (ka->sa.sa_flags & SA_SIGINFO) setup_rt_frame(ka, regs, sig, oldset, info); else setup_frame(ka, regs, sig, oldset); if (ka->sa.sa_flags & SA_ONESHOT) ka->sa.sa_handler = SIG_DFL; if (!(ka->sa.sa_flags & SA_NODEFER)) { spin_lock_irq(¤t->sigmask_lock); sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); sigaddset(¤t->blocked,sig); recalc_sigpending(current); spin_unlock_irq(¤t->sigmask_lock); } } static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka) { switch(regs->regs[0]) { case ERESTARTNOHAND: regs->regs[2] = EINTR; break; case ERESTARTSYS: if(!(ka->sa.sa_flags & SA_RESTART)) { regs->regs[2] = EINTR; break; } /* fallthrough */ case ERESTARTNOINTR: /* Userland will reload $v0. */ regs->regs[7] = regs->regs[26]; regs->cp0_epc -= 8; } regs->regs[0] = 0; /* Don't deal with this again. */ } asmlinkage int do_signal32(sigset_t *oldset, struct pt_regs *regs) { struct k_sigaction *ka; siginfo_t info; #if DEBUG_MIPS64 printk("%s: delivering signal.\n", current->comm); #endif if (!oldset) oldset = ¤t->blocked; for (;;) { unsigned long signr; spin_lock_irq(¤t->sigmask_lock); signr = dequeue_signal(¤t->blocked, &info); spin_unlock_irq(¤t->sigmask_lock); if (!signr) break; if ((current->flags & PF_PTRACED) && signr != SIGKILL) { /* Let the debugger run. */ current->exit_code = signr; current->state = TASK_STOPPED; notify_parent(current, SIGCHLD); schedule(); /* We're back. Did the debugger cancel the sig? */ if (!(signr = current->exit_code)) continue; current->exit_code = 0; /* The debugger continued. Ignore SIGSTOP. */ if (signr == SIGSTOP) continue; /* Update the siginfo structure. Is this good? */ if (signr != info.si_signo) { info.si_signo = signr; info.si_errno = 0; info.si_code = SI_USER; info.si_pid = current->p_pptr->pid; info.si_uid = current->p_pptr->uid; } /* If the (new) signal is now blocked, requeue it. */ if (sigismember(¤t->blocked, signr)) { send_sig_info(signr, &info, current); continue; } } ka = ¤t->sig->action[signr-1]; if (ka->sa.sa_handler == SIG_IGN) { if (signr != SIGCHLD) continue; /* Check for SIGCHLD: it's special. */ while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0) /* nothing */; continue; } if (ka->sa.sa_handler == SIG_DFL) { int exit_code = signr; /* Init gets no signals it doesn't want. */ if (current->pid == 1) continue; switch (signr) { case SIGCONT: case SIGCHLD: case SIGWINCH: continue; case SIGTSTP: case SIGTTIN: case SIGTTOU: if (is_orphaned_pgrp(current->pgrp)) continue; /* FALLTHRU */ case SIGSTOP: current->state = TASK_STOPPED; current->exit_code = signr; if (!(current->p_pptr->sig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP)) notify_parent(current, SIGCHLD); schedule(); continue; case SIGQUIT: case SIGILL: case SIGTRAP: case SIGABRT: case SIGFPE: case SIGSEGV: case SIGBUS: case SIGSYS: case SIGXCPU: case SIGXFSZ: if (do_coredump(signr, regs)) exit_code |= 0x80; /* FALLTHRU */ default: lock_kernel(); sigaddset(¤t->signal, signr); recalc_sigpending(current); current->flags |= PF_SIGNALED; do_exit(exit_code); /* NOTREACHED */ } } if (regs->regs[0]) syscall_restart(regs, ka); /* Whee! Actually deliver the signal. */ #if DEBUG_MIPS64 printk("%s: delivering signal.\n", __FUNCTION__); #endif handle_signal(signr, ka, &info, oldset, regs); return 1; } /* * Who's code doesn't conform to the restartable syscall convention * dies here!!! The li instruction, a single machine instruction, * must directly be followed by the syscall instruction. */ if (regs->regs[0]) { if (regs->regs[2] == ERESTARTNOHAND || regs->regs[2] == ERESTARTSYS || regs->regs[2] == ERESTARTNOINTR) { regs->regs[7] = regs->regs[26]; regs->cp0_epc -= 8; } } return 0; } extern asmlinkage int sys_sigprocmask(int how, old_sigset_t *set, old_sigset_t *oset); asmlinkage int sys32_sigprocmask(int how, old_sigset_t32 *set, old_sigset_t32 *oset) { old_sigset_t s; int ret; mm_segment_t old_fs = get_fs(); if (set && get_user (s, set)) return -EFAULT; set_fs (KERNEL_DS); ret = sys_sigprocmask(how, set ? &s : NULL, oset ? &s : NULL); set_fs (old_fs); if (ret) return ret; if (oset && put_user (s, oset)) return -EFAULT; return 0; } /* Dummies ... */ asmlinkage void sys32_sigpending(void) { panic(__FUNCTION__ " called."); } asmlinkage void sys32_rt_sigaction(void) { panic(__FUNCTION__ " called."); } asmlinkage void sys32_rt_sigprocmask(void) { panic(__FUNCTION__ " called."); } asmlinkage void sys32_rt_sigpending(void) { panic(__FUNCTION__ " called."); } asmlinkage void sys32_rt_sigtimedwait(void) { panic(__FUNCTION__ " called."); } asmlinkage void sys32_rt_sigqueueinfo(void) { panic(__FUNCTION__ " called."); }