1 files changed, 435 insertions, 0 deletions

diff --git a/arch/tile/kernel/compat_signal.c b/arch/tile/kernel/compat_signal.c
new file mode 100644
index 00000000000..d5efb215dd5
--- /dev/null
+++ b/arch/tile/kernel/compat_signal.c
@@ -0,0 +1,435 @@
+/*
+ * 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 <asm/syscalls.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 __packed;
+};
+
+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 __force __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 ? (stack_t __user __force *)&uss : NULL,
+                             (stack_t __user __force *)&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(&current->sighand->siglock);
+        current->blocked = set;
+        recalc_sigpending();
+        spin_unlock_irq(&current->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 __force *)-1UL;
+
+        /* 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;
+}