/* * 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 - 2000, 2006 Ralf Baechle * Copyright (C) 1999, 2000 Silicon Graphics, Inc. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "signal-common.h" static int (*save_fp_context32)(struct sigcontext32 __user *sc); static int (*restore_fp_context32)(struct sigcontext32 __user *sc); extern asmlinkage int _save_fp_context32(struct sigcontext32 __user *sc); extern asmlinkage int _restore_fp_context32(struct sigcontext32 __user *sc); extern asmlinkage int fpu_emulator_save_context32(struct sigcontext32 __user *sc); extern asmlinkage int fpu_emulator_restore_context32(struct sigcontext32 __user *sc); /* * Including would give use the 64-bit syscall numbers ... */ #define __NR_O32_restart_syscall 4253 /* 32-bit compatibility types */ typedef unsigned int __sighandler32_t; typedef void (*vfptr_t)(void); struct sigaction32 { unsigned int sa_flags; __sighandler32_t sa_handler; compat_sigset_t sa_mask; }; struct ucontext32 { u32 uc_flags; s32 uc_link; compat_stack_t uc_stack; struct sigcontext32 uc_mcontext; compat_sigset_t uc_sigmask; /* mask last for extensibility */ }; struct sigframe32 { u32 sf_ass[4]; /* argument save space for o32 */ u32 sf_pad[2]; /* Was: signal trampoline */ struct sigcontext32 sf_sc; compat_sigset_t sf_mask; }; struct rt_sigframe32 { u32 rs_ass[4]; /* argument save space for o32 */ u32 rs_pad[2]; /* Was: signal trampoline */ compat_siginfo_t rs_info; struct ucontext32 rs_uc; }; /* * sigcontext handlers */ static int protected_save_fp_context32(struct sigcontext32 __user *sc) { int err; while (1) { lock_fpu_owner(); own_fpu_inatomic(1); err = save_fp_context32(sc); /* this might fail */ unlock_fpu_owner(); if (likely(!err)) break; /* touch the sigcontext and try again */ err = __put_user(0, &sc->sc_fpregs[0]) | __put_user(0, &sc->sc_fpregs[31]) | __put_user(0, &sc->sc_fpc_csr); if (err) break; /* really bad sigcontext */ } return err; } static int protected_restore_fp_context32(struct sigcontext32 __user *sc) { int err, tmp __maybe_unused; while (1) { lock_fpu_owner(); own_fpu_inatomic(0); err = restore_fp_context32(sc); /* this might fail */ unlock_fpu_owner(); if (likely(!err)) break; /* touch the sigcontext and try again */ err = __get_user(tmp, &sc->sc_fpregs[0]) | __get_user(tmp, &sc->sc_fpregs[31]) | __get_user(tmp, &sc->sc_fpc_csr); if (err) break; /* really bad sigcontext */ } return err; } static int setup_sigcontext32(struct pt_regs *regs, struct sigcontext32 __user *sc) { int err = 0; int i; u32 used_math; err |= __put_user(regs->cp0_epc, &sc->sc_pc); err |= __put_user(0, &sc->sc_regs[0]); for (i = 1; i < 32; i++) err |= __put_user(regs->regs[i], &sc->sc_regs[i]); err |= __put_user(regs->hi, &sc->sc_mdhi); err |= __put_user(regs->lo, &sc->sc_mdlo); if (cpu_has_dsp) { err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp); err |= __put_user(mfhi1(), &sc->sc_hi1); err |= __put_user(mflo1(), &sc->sc_lo1); err |= __put_user(mfhi2(), &sc->sc_hi2); err |= __put_user(mflo2(), &sc->sc_lo2); err |= __put_user(mfhi3(), &sc->sc_hi3); err |= __put_user(mflo3(), &sc->sc_lo3); } used_math = !!used_math(); err |= __put_user(used_math, &sc->sc_used_math); if (used_math) { /* * Save FPU state to signal context. Signal handler * will "inherit" current FPU state. */ err |= protected_save_fp_context32(sc); } return err; } static int check_and_restore_fp_context32(struct sigcontext32 __user *sc) { int err, sig; err = sig = fpcsr_pending(&sc->sc_fpc_csr); if (err > 0) err = 0; err |= protected_restore_fp_context32(sc); return err ?: sig; } static int restore_sigcontext32(struct pt_regs *regs, struct sigcontext32 __user *sc) { u32 used_math; int err = 0; s32 treg; int i; /* Always make any pending restarted system calls return -EINTR */ current_thread_info()->restart_block.fn = do_no_restart_syscall; 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); if (cpu_has_dsp) { err |= __get_user(treg, &sc->sc_hi1); mthi1(treg); err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg); err |= __get_user(treg, &sc->sc_hi2); mthi2(treg); err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg); err |= __get_user(treg, &sc->sc_hi3); mthi3(treg); err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg); err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK); } for (i = 1; i < 32; i++) err |= __get_user(regs->regs[i], &sc->sc_regs[i]); err |= __get_user(used_math, &sc->sc_used_math); conditional_used_math(used_math); if (used_math) { /* restore fpu context if we have used it before */ if (!err) err = check_and_restore_fp_context32(sc); } else { /* signal handler may have used FPU. Give it up. */ lose_fpu(0); } return err; } /* * */ extern void __put_sigset_unknown_nsig(void); extern void __get_sigset_unknown_nsig(void); static inline int put_sigset(const sigset_t *kbuf, compat_sigset_t __user *ubuf) { int err = 0; if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf))) return -EFAULT; switch (_NSIG_WORDS) { default: __put_sigset_unknown_nsig(); case 2: err |= __put_user(kbuf->sig[1] >> 32, &ubuf->sig[3]); err |= __put_user(kbuf->sig[1] & 0xffffffff, &ubuf->sig[2]); case 1: err |= __put_user(kbuf->sig[0] >> 32, &ubuf->sig[1]); err |= __put_user(kbuf->sig[0] & 0xffffffff, &ubuf->sig[0]); } return err; } static inline int get_sigset(sigset_t *kbuf, const compat_sigset_t __user *ubuf) { int err = 0; unsigned long sig[4]; if (!access_ok(VERIFY_READ, ubuf, sizeof(*ubuf))) return -EFAULT; switch (_NSIG_WORDS) { default: __get_sigset_unknown_nsig(); case 2: err |= __get_user(sig[3], &ubuf->sig[3]); err |= __get_user(sig[2], &ubuf->sig[2]); kbuf->sig[1] = sig[2] | (sig[3] << 32); case 1: err |= __get_user(sig[1], &ubuf->sig[1]); err |= __get_user(sig[0], &ubuf->sig[0]); kbuf->sig[0] = sig[0] | (sig[1] << 32); } return err; } /* * Atomically swap in the new signal mask, and wait for a signal. */ asmlinkage int sys32_sigsuspend(nabi_no_regargs struct pt_regs regs) { compat_sigset_t __user *uset; sigset_t newset; uset = (compat_sigset_t __user *) regs.regs[4]; if (get_sigset(&newset, uset)) return -EFAULT; return sigsuspend(&newset); } SYSCALL_DEFINE3(32_sigaction, long, sig, const struct sigaction32 __user *, act, struct sigaction32 __user *, oact) { struct k_sigaction new_ka, old_ka; int ret; int err = 0; if (act) { old_sigset_t mask; s32 handler; if (!access_ok(VERIFY_READ, act, sizeof(*act))) return -EFAULT; err |= __get_user(handler, &act->sa_handler); new_ka.sa.sa_handler = (void __user *)(s64)handler; err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags); err |= __get_user(mask, &act->sa_mask.sig[0]); 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((u32)(u64)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]); if (err) return -EFAULT; } return ret; } int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from) { int err; if (!access_ok (VERIFY_WRITE, to, sizeof(compat_siginfo_t))) return -EFAULT; /* If you change siginfo_t structure, please be sure this code is fixed accordingly. It should never copy any pad contained in the structure to avoid security leaks, but must copy the generic 3 ints plus the relevant union member. This routine must convert siginfo from 64bit to 32bit as well at the same time. */ err = __put_user(from->si_signo, &to->si_signo); err |= __put_user(from->si_errno, &to->si_errno); err |= __put_user((short)from->si_code, &to->si_code); if (from->si_code < 0) err |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE); else { switch (from->si_code >> 16) { case __SI_TIMER >> 16: err |= __put_user(from->si_tid, &to->si_tid); err |= __put_user(from->si_overrun, &to->si_overrun); err |= __put_user(from->si_int, &to->si_int); break; case __SI_CHLD >> 16: err |= __put_user(from->si_utime, &to->si_utime); err |= __put_user(from->si_stime, &to->si_stime); err |= __put_user(from->si_status, &to->si_status); default: err |= __put_user(from->si_pid, &to->si_pid); err |= __put_user(from->si_uid, &to->si_uid); break; case __SI_FAULT >> 16: err |= __put_user((unsigned long)from->si_addr, &to->si_addr); break; case __SI_POLL >> 16: err |= __put_user(from->si_band, &to->si_band); err |= __put_user(from->si_fd, &to->si_fd); break; case __SI_RT >> 16: /* This is not generated by the kernel as of now. */ case __SI_MESGQ >> 16: err |= __put_user(from->si_pid, &to->si_pid); err |= __put_user(from->si_uid, &to->si_uid); err |= __put_user(from->si_int, &to->si_int); break; } } return err; } int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from) { memset(to, 0, sizeof *to); if (copy_from_user(to, from, 3*sizeof(int)) || copy_from_user(to->_sifields._pad, from->_sifields._pad, SI_PAD_SIZE32)) return -EFAULT; return 0; } asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs) { struct sigframe32 __user *frame; sigset_t blocked; int sig; frame = (struct sigframe32 __user *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) goto badframe; if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask)) goto badframe; set_current_blocked(&blocked); sig = restore_sigcontext32(®s, &frame->sf_sc); if (sig < 0) goto badframe; else if (sig) force_sig(sig, current); /* * Don't let your children do this ... */ __asm__ __volatile__( "move\t$29, %0\n\t" "j\tsyscall_exit" :/* no outputs */ :"r" (®s)); /* Unreached */ badframe: force_sig(SIGSEGV, current); } asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs) { struct rt_sigframe32 __user *frame; sigset_t set; int sig; frame = (struct rt_sigframe32 __user *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) goto badframe; if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask)) goto badframe; set_current_blocked(&set); sig = restore_sigcontext32(®s, &frame->rs_uc.uc_mcontext); if (sig < 0) goto badframe; else if (sig) force_sig(sig, current); if (compat_restore_altstack(&frame->rs_uc.uc_stack)) goto badframe; /* * Don't let your children do this ... */ __asm__ __volatile__( "move\t$29, %0\n\t" "j\tsyscall_exit" :/* no outputs */ :"r" (®s)); /* Unreached */ badframe: force_sig(SIGSEGV, current); } static int setup_frame_32(void *sig_return, struct k_sigaction *ka, struct pt_regs *regs, int signr, sigset_t *set) { struct sigframe32 __user *frame; int err = 0; frame = get_sigframe(ka, regs, sizeof(*frame)); if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) goto give_sigsegv; err |= setup_sigcontext32(regs, &frame->sf_sc); err |= __copy_conv_sigset_to_user(&frame->sf_mask, 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) sig_return; regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler; DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", current->comm, current->pid, frame, regs->cp0_epc, regs->regs[31]); return 0; give_sigsegv: force_sigsegv(signr, current); return -EFAULT; } static int setup_rt_frame_32(void *sig_return, struct k_sigaction *ka, struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info) { struct rt_sigframe32 __user *frame; int err = 0; frame = get_sigframe(ka, regs, sizeof(*frame)); if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) goto give_sigsegv; /* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */ err |= copy_siginfo_to_user32(&frame->rs_info, info); /* Create the ucontext. */ err |= __put_user(0, &frame->rs_uc.uc_flags); err |= __put_user(0, &frame->rs_uc.uc_link); err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]); err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext); err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, 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_sigframe32. */ 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) sig_return; regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler; DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", current->comm, current->pid, frame, regs->cp0_epc, regs->regs[31]); return 0; give_sigsegv: force_sigsegv(signr, current); return -EFAULT; } /* * o32 compatibility on 64-bit kernels, without DSP ASE */ struct mips_abi mips_abi_32 = { .setup_frame = setup_frame_32, .signal_return_offset = offsetof(struct mips_vdso, o32_signal_trampoline), .setup_rt_frame = setup_rt_frame_32, .rt_signal_return_offset = offsetof(struct mips_vdso, o32_rt_signal_trampoline), .restart = __NR_O32_restart_syscall }; SYSCALL_DEFINE4(32_rt_sigaction, int, sig, const struct sigaction32 __user *, act, struct sigaction32 __user *, oact, unsigned int, sigsetsize) { struct k_sigaction new_sa, old_sa; int ret = -EINVAL; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) goto out; if (act) { s32 handler; int err = 0; if (!access_ok(VERIFY_READ, act, sizeof(*act))) return -EFAULT; err |= __get_user(handler, &act->sa_handler); new_sa.sa.sa_handler = (void __user *)(s64)handler; err |= __get_user(new_sa.sa.sa_flags, &act->sa_flags); err |= get_sigset(&new_sa.sa.sa_mask, &act->sa_mask); if (err) return -EFAULT; } ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL); if (!ret && oact) { int err = 0; if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact))) return -EFAULT; err |= __put_user((u32)(u64)old_sa.sa.sa_handler, &oact->sa_handler); err |= __put_user(old_sa.sa.sa_flags, &oact->sa_flags); err |= put_sigset(&old_sa.sa.sa_mask, &oact->sa_mask); if (err) return -EFAULT; } out: return ret; } SYSCALL_DEFINE3(32_rt_sigqueueinfo, int, pid, int, sig, compat_siginfo_t __user *, uinfo) { siginfo_t info; int ret; mm_segment_t old_fs = get_fs(); if (copy_from_user(&info, uinfo, 3*sizeof(int)) || copy_from_user(info._sifields._pad, uinfo->_sifields._pad, SI_PAD_SIZE)) return -EFAULT; set_fs(KERNEL_DS); ret = sys_rt_sigqueueinfo(pid, sig, (siginfo_t __user *)&info); set_fs(old_fs); return ret; } static int signal32_init(void) { if (cpu_has_fpu) { save_fp_context32 = _save_fp_context32; restore_fp_context32 = _restore_fp_context32; } else { save_fp_context32 = fpu_emulator_save_context32; restore_fp_context32 = fpu_emulator_restore_context32; } return 0; } arch_initcall(signal32_init);