diff options
Diffstat (limited to 'arch/tile/kernel/compat_signal.c')
| -rw-r--r-- | arch/tile/kernel/compat_signal.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/arch/tile/kernel/compat_signal.c b/arch/tile/kernel/compat_signal.c new file mode 100644 index 000000000000..9fa4ba8ed5f4 --- /dev/null +++ b/arch/tile/kernel/compat_signal.c @@ -0,0 +1,433 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * 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, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#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/unistd.h> +#include <linux/stddef.h> +#include <linux/personality.h> +#include <linux/suspend.h> +#include <linux/ptrace.h> +#include <linux/elf.h> +#include <linux/compat.h> +#include <linux/syscalls.h> +#include <linux/uaccess.h> +#include <asm/processor.h> +#include <asm/ucontext.h> +#include <asm/sigframe.h> +#include <arch/interrupts.h> + +struct compat_sigaction { + compat_uptr_t sa_handler; + compat_ulong_t sa_flags; + compat_uptr_t sa_restorer; + sigset_t sa_mask; /* mask last for extensibility */ +}; + +struct compat_sigaltstack { + compat_uptr_t ss_sp; + int ss_flags; + compat_size_t ss_size; +}; + +struct compat_ucontext { + compat_ulong_t uc_flags; + compat_uptr_t uc_link; + struct compat_sigaltstack uc_stack; + struct sigcontext uc_mcontext; + sigset_t uc_sigmask; /* mask last for extensibility */ +}; + +struct compat_siginfo { + int si_signo; + int si_errno; + int si_code; + + union { + int _pad[SI_PAD_SIZE]; + + /* kill() */ + struct { + unsigned int _pid; /* sender's pid */ + unsigned int _uid; /* sender's uid */ + } _kill; + + /* POSIX.1b timers */ + struct { + compat_timer_t _tid; /* timer id */ + int _overrun; /* overrun count */ + compat_sigval_t _sigval; /* same as below */ + int _sys_private; /* not to be passed to user */ + int _overrun_incr; /* amount to add to overrun */ + } _timer; + + /* POSIX.1b signals */ + struct { + unsigned int _pid; /* sender's pid */ + unsigned int _uid; /* sender's uid */ + compat_sigval_t _sigval; + } _rt; + + /* SIGCHLD */ + struct { + unsigned int _pid; /* which child */ + unsigned int _uid; /* sender's uid */ + int _status; /* exit code */ + compat_clock_t _utime; + compat_clock_t _stime; + } _sigchld; + + /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */ + struct { + unsigned int _addr; /* faulting insn/memory ref. */ +#ifdef __ARCH_SI_TRAPNO + int _trapno; /* TRAP # which caused the signal */ +#endif + } _sigfault; + + /* SIGPOLL */ + struct { + int _band; /* POLL_IN, POLL_OUT, POLL_MSG */ + int _fd; + } _sigpoll; + } _sifields; +}; + +struct compat_rt_sigframe { + unsigned char save_area[C_ABI_SAVE_AREA_SIZE]; /* caller save area */ + struct compat_siginfo info; + struct compat_ucontext uc; +}; + +#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) + +long compat_sys_rt_sigaction(int sig, struct compat_sigaction __user *act, + struct compat_sigaction __user *oact, + size_t 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) { + compat_uptr_t handler, restorer; + + if (!access_ok(VERIFY_READ, act, sizeof(*act)) || + __get_user(handler, &act->sa_handler) || + __get_user(new_sa.sa.sa_flags, &act->sa_flags) || + __get_user(restorer, &act->sa_restorer) || + __copy_from_user(&new_sa.sa.sa_mask, &act->sa_mask, + sizeof(sigset_t))) + return -EFAULT; + new_sa.sa.sa_handler = compat_ptr(handler); + new_sa.sa.sa_restorer = compat_ptr(restorer); + } + + ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL); + + if (!ret && oact) { + if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || + __put_user(ptr_to_compat(old_sa.sa.sa_handler), + &oact->sa_handler) || + __put_user(ptr_to_compat(old_sa.sa.sa_restorer), + &oact->sa_restorer) || + __put_user(old_sa.sa.sa_flags, &oact->sa_flags) || + __copy_to_user(&oact->sa_mask, &old_sa.sa.sa_mask, + sizeof(sigset_t))) + return -EFAULT; + } +out: + return ret; +} + +long compat_sys_rt_sigqueueinfo(int pid, int sig, + struct compat_siginfo __user *uinfo) +{ + siginfo_t info; + int ret; + mm_segment_t old_fs = get_fs(); + + if (copy_siginfo_from_user32(&info, uinfo)) + return -EFAULT; + set_fs(KERNEL_DS); + ret = sys_rt_sigqueueinfo(pid, sig, (siginfo_t __user *)&info); + set_fs(old_fs); + return ret; +} + +int copy_siginfo_to_user32(struct compat_siginfo __user *to, siginfo_t *from) +{ + int err; + + if (!access_ok(VERIFY_WRITE, to, sizeof(struct compat_siginfo))) + return -EFAULT; + + /* If you change siginfo_t structure, please make sure that + 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. */ + 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 |= __put_user(from->si_pid, &to->si_pid); + err |= __put_user(from->si_uid, &to->si_uid); + err |= __put_user(ptr_to_compat(from->si_ptr), &to->si_ptr); + } else { + /* + * First 32bits of unions are always present: + * si_pid === si_band === si_tid === si_addr(LS half) + */ + err |= __put_user(from->_sifields._pad[0], + &to->_sifields._pad[0]); + switch (from->si_code >> 16) { + case __SI_FAULT >> 16: + 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); + /* FALL THROUGH */ + default: + case __SI_KILL >> 16: + err |= __put_user(from->si_uid, &to->si_uid); + break; + case __SI_POLL >> 16: + err |= __put_user(from->si_fd, &to->si_fd); + break; + case __SI_TIMER >> 16: + err |= __put_user(from->si_overrun, &to->si_overrun); + err |= __put_user(ptr_to_compat(from->si_ptr), + &to->si_ptr); + break; + /* This is not generated by the kernel as of now. */ + case __SI_RT >> 16: + case __SI_MESGQ >> 16: + 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, struct compat_siginfo __user *from) +{ + int err; + u32 ptr32; + + if (!access_ok(VERIFY_READ, from, sizeof(struct compat_siginfo))) + return -EFAULT; + + err = __get_user(to->si_signo, &from->si_signo); + err |= __get_user(to->si_errno, &from->si_errno); + err |= __get_user(to->si_code, &from->si_code); + + err |= __get_user(to->si_pid, &from->si_pid); + err |= __get_user(to->si_uid, &from->si_uid); + err |= __get_user(ptr32, &from->si_ptr); + to->si_ptr = compat_ptr(ptr32); + + return err; +} + +long _compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr, + struct compat_sigaltstack __user *uoss_ptr, + struct pt_regs *regs) +{ + stack_t uss, uoss; + int ret; + mm_segment_t seg; + + if (uss_ptr) { + u32 ptr; + + memset(&uss, 0, sizeof(stack_t)); + if (!access_ok(VERIFY_READ, uss_ptr, sizeof(*uss_ptr)) || + __get_user(ptr, &uss_ptr->ss_sp) || + __get_user(uss.ss_flags, &uss_ptr->ss_flags) || + __get_user(uss.ss_size, &uss_ptr->ss_size)) + return -EFAULT; + uss.ss_sp = compat_ptr(ptr); + } + seg = get_fs(); + set_fs(KERNEL_DS); + ret = do_sigaltstack(uss_ptr ? &uss : NULL, &uoss, + (unsigned long)compat_ptr(regs->sp)); + set_fs(seg); + if (ret >= 0 && uoss_ptr) { + if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(*uoss_ptr)) || + __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) || + __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) || + __put_user(uoss.ss_size, &uoss_ptr->ss_size)) + ret = -EFAULT; + } + return ret; +} + +long _compat_sys_rt_sigreturn(struct pt_regs *regs) +{ + struct compat_rt_sigframe __user *frame = + (struct compat_rt_sigframe __user *) compat_ptr(regs->sp); + sigset_t set; + long r0; + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + 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); + + if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0)) + goto badframe; + + if (_compat_sys_sigaltstack(&frame->uc.uc_stack, NULL, regs) != 0) + goto badframe; + + return r0; + +badframe: + force_sig(SIGSEGV, current); + return 0; +} + +/* + * Determine which stack to use.. + */ +static inline void __user *compat_get_sigframe(struct k_sigaction *ka, + struct pt_regs *regs, + size_t frame_size) +{ + unsigned long sp; + + /* Default to using normal stack */ + sp = (unsigned long)compat_ptr(regs->sp); + + /* + * If we are on the alternate signal stack and would overflow + * it, don't. Return an always-bogus address instead so we + * will die with SIGSEGV. + */ + if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size))) + return (void __user *) -1L; + + /* This is the X/Open sanctioned signal stack switching. */ + if (ka->sa.sa_flags & SA_ONSTACK) { + if (sas_ss_flags(sp) == 0) + sp = current->sas_ss_sp + current->sas_ss_size; + } + + sp -= frame_size; + /* + * Align the stack pointer according to the TILE ABI, + * i.e. so that on function entry (sp & 15) == 0. + */ + sp &= -16UL; + return (void __user *) sp; +} + +int compat_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, + sigset_t *set, struct pt_regs *regs) +{ + unsigned long restorer; + struct compat_rt_sigframe __user *frame; + int err = 0; + int usig; + + frame = compat_get_sigframe(ka, regs, sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + goto give_sigsegv; + + usig = current_thread_info()->exec_domain + && current_thread_info()->exec_domain->signal_invmap + && sig < 32 + ? current_thread_info()->exec_domain->signal_invmap[sig] + : sig; + + /* Always write at least the signal number for the stack backtracer. */ + if (ka->sa.sa_flags & SA_SIGINFO) { + /* At sigreturn time, restore the callee-save registers too. */ + err |= copy_siginfo_to_user32(&frame->info, info); + regs->flags |= PT_FLAGS_RESTORE_REGS; + } else { + err |= __put_user(info->si_signo, &frame->info.si_signo); + } + + /* Create the ucontext. */ + err |= __clear_user(&frame->save_area, sizeof(frame->save_area)); + err |= __put_user(0, &frame->uc.uc_flags); + err |= __put_user(0, &frame->uc.uc_link); + err |= __put_user(ptr_to_compat((void *)(current->sas_ss_sp)), + &frame->uc.uc_stack.ss_sp); + err |= __put_user(sas_ss_flags(regs->sp), + &frame->uc.uc_stack.ss_flags); + err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); + err |= setup_sigcontext(&frame->uc.uc_mcontext, regs); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + if (err) + goto give_sigsegv; + + restorer = VDSO_BASE; + if (ka->sa.sa_flags & SA_RESTORER) + restorer = ptr_to_compat_reg(ka->sa.sa_restorer); + + /* + * Set up registers for signal handler. + * Registers that we don't modify keep the value they had from + * user-space at the time we took the signal. + */ + regs->pc = ptr_to_compat_reg(ka->sa.sa_handler); + regs->ex1 = PL_ICS_EX1(USER_PL, 1); /* set crit sec in handler */ + regs->sp = ptr_to_compat_reg(frame); + regs->lr = restorer; + regs->regs[0] = (unsigned long) usig; + + if (ka->sa.sa_flags & SA_SIGINFO) { + /* Need extra arguments, so mark to restore caller-saves. */ + regs->regs[1] = ptr_to_compat_reg(&frame->info); + regs->regs[2] = ptr_to_compat_reg(&frame->uc); + regs->flags |= PT_FLAGS_CALLER_SAVES; + } + + /* + * Notify any tracer that was single-stepping it. + * The tracer may want to single-step inside the + * handler too. + */ + if (test_thread_flag(TIF_SINGLESTEP)) + ptrace_notify(SIGTRAP); + + return 0; + +give_sigsegv: + force_sigsegv(sig, current); + return -EFAULT; +} |