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linux/arch/sparc64/kernel/signal32.c
David S. Miller 28e6103665 sparc: Fix debugger syscall restart interactions. 
So, forever, we've had this ptrace_signal_deliver implementation
which tries to handle all of the nasties that can occur when the
debugger looks at a process about to take a signal.  It's meant
to address all of these issues inside of the kernel so that the
debugger need not be mindful of such things.

Problem is, this doesn't work.

The idea was that we should do the syscall restart business first, so
that the debugger captures that state.  Otherwise, if the debugger for
example saves the child's state, makes the child execute something
else, then restores the saved state, we won't handle the syscall
restart properly because we lose the "we're in a syscall" state.

The code here worked for most cases, but if the debugger actually
passes the signal through to the child unaltered, it's possible that
we would do a syscall restart when we shouldn't have.

In particular this breaks the case of debugging a process under a gdb
which is being debugged by yet another gdb.  gdb uses sigsuspend
to wait for SIGCHLD of the inferior, but if gdb itself is being
debugged by a top-level gdb we get a ptrace_stop().  The top-level gdb
does a PTRACE_CONT with SIGCHLD to let the inferior gdb see the
signal.  But ptrace_signal_deliver() assumed the debugger would cancel
out the signal and therefore did a syscall restart, because the return
error was ERESTARTNOHAND.

Fix this by simply making ptrace_signal_deliver() a nop, and providing
a way for the debugger to control system call restarting properly:

1) Report a "in syscall" software bit in regs->{tstate,psr}.
   It is set early on in trap entry to a system call and is fully
   visible to the debugger via ptrace() and regsets.

2) Test this bit right before doing a syscall restart.  We have
   to do a final recheck right after get_signal_to_deliver() in
   case the debugger cleared the bit during ptrace_stop().

3) Clear the bit in trap return so we don't accidently try to set
   that bit in the real register.

As a result we also get a ptrace_{is,clear}_syscall() for sparc32 just
like sparc64 has.

M68K has this same exact bug, and is now the only other user of the
ptrace_signal_deliver hook.  It needs to be fixed in the same exact
way as sparc.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-11 02:07:19 -07:00

898 lines
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/* arch/sparc64/kernel/signal32.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#include <linux/sched.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/mm.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
#include <linux/compat.h>
#include <linux/bitops.h>
#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/pgtable.h>
#include <asm/psrcompat.h>
#include <asm/fpumacro.h>
#include <asm/visasm.h>
#include <asm/compat_signal.h>
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
/* This magic should be in g_upper[0] for all upper parts
* to be valid.
*/
#define SIGINFO_EXTRA_V8PLUS_MAGIC 0x130e269
typedef struct {
unsigned int g_upper[8];
unsigned int o_upper[8];
unsigned int asi;
} siginfo_extra_v8plus_t;
struct signal_frame32 {
struct sparc_stackf32 ss;
__siginfo32_t info;
/* __siginfo_fpu32_t * */ u32 fpu_save;
unsigned int insns[2];
unsigned int extramask[_COMPAT_NSIG_WORDS - 1];
unsigned int extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
/* Only valid if (info.si_regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
siginfo_extra_v8plus_t v8plus;
__siginfo_fpu_t fpu_state;
};
typedef struct compat_siginfo{
int si_signo;
int si_errno;
int si_code;
union {
int _pad[SI_PAD_SIZE32];
/* kill() */
struct {
compat_pid_t _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 */
} _timer;
/* POSIX.1b signals */
struct {
compat_pid_t _pid; /* sender's pid */
unsigned int _uid; /* sender's uid */
compat_sigval_t _sigval;
} _rt;
/* SIGCHLD */
struct {
compat_pid_t _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, SIGEMT */
struct {
u32 _addr; /* faulting insn/memory ref. */
int _trapno;
} _sigfault;
/* SIGPOLL */
struct {
int _band; /* POLL_IN, POLL_OUT, POLL_MSG */
int _fd;
} _sigpoll;
} _sifields;
}compat_siginfo_t;
struct rt_signal_frame32 {
struct sparc_stackf32 ss;
compat_siginfo_t info;
struct pt_regs32 regs;
compat_sigset_t mask;
/* __siginfo_fpu32_t * */ u32 fpu_save;
unsigned int insns[2];
stack_t32 stack;
unsigned int extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
/* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
siginfo_extra_v8plus_t v8plus;
__siginfo_fpu_t fpu_state;
};
/* Align macros */
#define SF_ALIGNEDSZ (((sizeof(struct signal_frame32) + 7) & (~7)))
#define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame32) + 7) & (~7)))
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(from->si_trapno, &to->si_trapno);
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;
}
/* CAUTION: This is just a very minimalist implementation for the
* sake of compat_sys_rt_sigqueueinfo()
*/
int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
{
if (!access_ok(VERIFY_WRITE, from, sizeof(compat_siginfo_t)))
return -EFAULT;
if (copy_from_user(to, from, 3*sizeof(int)) ||
copy_from_user(to->_sifields._pad, from->_sifields._pad,
SI_PAD_SIZE))
return -EFAULT;
return 0;
}
static int restore_fpu_state32(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
unsigned long *fpregs = current_thread_info()->fpregs;
unsigned long fprs;
int err;
err = __get_user(fprs, &fpu->si_fprs);
fprs_write(0);
regs->tstate &= ~TSTATE_PEF;
if (fprs & FPRS_DL)
err |= copy_from_user(fpregs, &fpu->si_float_regs[0], (sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_from_user(fpregs+16, &fpu->si_float_regs[32], (sizeof(unsigned int) * 32));
err |= __get_user(current_thread_info()->xfsr[0], &fpu->si_fsr);
err |= __get_user(current_thread_info()->gsr[0], &fpu->si_gsr);
current_thread_info()->fpsaved[0] |= fprs;
return err;
}
void do_sigreturn32(struct pt_regs *regs)
{
struct signal_frame32 __user *sf;
unsigned int psr;
unsigned pc, npc, fpu_save;
sigset_t set;
unsigned seta[_COMPAT_NSIG_WORDS];
int err, i;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
synchronize_user_stack();
regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
sf = (struct signal_frame32 __user *) regs->u_regs[UREG_FP];
/* 1. Make sure we are not getting garbage from the user */
if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
(((unsigned long) sf) & 3))
goto segv;
get_user(pc, &sf->info.si_regs.pc);
__get_user(npc, &sf->info.si_regs.npc);
if ((pc | npc) & 3)
goto segv;
if (test_thread_flag(TIF_32BIT)) {
pc &= 0xffffffff;
npc &= 0xffffffff;
}
regs->tpc = pc;
regs->tnpc = npc;
/* 2. Restore the state */
err = __get_user(regs->y, &sf->info.si_regs.y);
err |= __get_user(psr, &sf->info.si_regs.psr);
for (i = UREG_G1; i <= UREG_I7; i++)
err |= __get_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
err |= __get_user(i, &sf->v8plus.g_upper[0]);
if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
unsigned long asi;
for (i = UREG_G1; i <= UREG_I7; i++)
err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
err |= __get_user(asi, &sf->v8plus.asi);
regs->tstate &= ~TSTATE_ASI;
regs->tstate |= ((asi & 0xffUL) << 24UL);
}
}
/* User can only change condition codes in %tstate. */
regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
regs->tstate |= psr_to_tstate_icc(psr);
/* Prevent syscall restart. */
pt_regs_clear_syscall(regs);
err |= __get_user(fpu_save, &sf->fpu_save);
if (fpu_save)
err |= restore_fpu_state32(regs, &sf->fpu_state);
err |= __get_user(seta[0], &sf->info.si_mask);
err |= copy_from_user(seta+1, &sf->extramask,
(_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
if (err)
goto segv;
switch (_NSIG_WORDS) {
case 4: set.sig[3] = seta[6] + (((long)seta[7]) << 32);
case 3: set.sig[2] = seta[4] + (((long)seta[5]) << 32);
case 2: set.sig[1] = seta[2] + (((long)seta[3]) << 32);
case 1: set.sig[0] = seta[0] + (((long)seta[1]) << 32);
}
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
return;
segv:
force_sig(SIGSEGV, current);
}
asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
{
struct rt_signal_frame32 __user *sf;
unsigned int psr, pc, npc, fpu_save, u_ss_sp;
mm_segment_t old_fs;
sigset_t set;
compat_sigset_t seta;
stack_t st;
int err, i;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
synchronize_user_stack();
regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
sf = (struct rt_signal_frame32 __user *) regs->u_regs[UREG_FP];
/* 1. Make sure we are not getting garbage from the user */
if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
(((unsigned long) sf) & 3))
goto segv;
get_user(pc, &sf->regs.pc);
__get_user(npc, &sf->regs.npc);
if ((pc | npc) & 3)
goto segv;
if (test_thread_flag(TIF_32BIT)) {
pc &= 0xffffffff;
npc &= 0xffffffff;
}
regs->tpc = pc;
regs->tnpc = npc;
/* 2. Restore the state */
err = __get_user(regs->y, &sf->regs.y);
err |= __get_user(psr, &sf->regs.psr);
for (i = UREG_G1; i <= UREG_I7; i++)
err |= __get_user(regs->u_regs[i], &sf->regs.u_regs[i]);
if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
err |= __get_user(i, &sf->v8plus.g_upper[0]);
if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
unsigned long asi;
for (i = UREG_G1; i <= UREG_I7; i++)
err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
err |= __get_user(asi, &sf->v8plus.asi);
regs->tstate &= ~TSTATE_ASI;
regs->tstate |= ((asi & 0xffUL) << 24UL);
}
}
/* User can only change condition codes in %tstate. */
regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
regs->tstate |= psr_to_tstate_icc(psr);
/* Prevent syscall restart. */
pt_regs_clear_syscall(regs);
err |= __get_user(fpu_save, &sf->fpu_save);
if (fpu_save)
err |= restore_fpu_state32(regs, &sf->fpu_state);
err |= copy_from_user(&seta, &sf->mask, sizeof(compat_sigset_t));
err |= __get_user(u_ss_sp, &sf->stack.ss_sp);
st.ss_sp = compat_ptr(u_ss_sp);
err |= __get_user(st.ss_flags, &sf->stack.ss_flags);
err |= __get_user(st.ss_size, &sf->stack.ss_size);
if (err)
goto segv;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
old_fs = get_fs();
set_fs(KERNEL_DS);
do_sigaltstack((stack_t __user *) &st, NULL, (unsigned long)sf);
set_fs(old_fs);
switch (_NSIG_WORDS) {
case 4: set.sig[3] = seta.sig[6] + (((long)seta.sig[7]) << 32);
case 3: set.sig[2] = seta.sig[4] + (((long)seta.sig[5]) << 32);
case 2: set.sig[1] = seta.sig[2] + (((long)seta.sig[3]) << 32);
case 1: set.sig[0] = seta.sig[0] + (((long)seta.sig[1]) << 32);
}
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
return;
segv:
force_sig(SIGSEGV, current);
}
/* Checks if the fp is valid */
static int invalid_frame_pointer(void __user *fp, int fplen)
{
if ((((unsigned long) fp) & 7) || ((unsigned long)fp) > 0x100000000ULL - fplen)
return 1;
return 0;
}
static void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize)
{
unsigned long sp;
regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
sp = regs->u_regs[UREG_FP];
/*
* 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 - framesize)))
return (void __user *) -1L;
/* This is the X/Open sanctioned signal stack switching. */
if (sa->sa_flags & SA_ONSTACK) {
if (sas_ss_flags(sp) == 0)
sp = current->sas_ss_sp + current->sas_ss_size;
}
/* Always align the stack frame. This handles two cases. First,
* sigaltstack need not be mindful of platform specific stack
* alignment. Second, if we took this signal because the stack
* is not aligned properly, we'd like to take the signal cleanly
* and report that.
*/
sp &= ~7UL;
return (void __user *)(sp - framesize);
}
static int save_fpu_state32(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
unsigned long *fpregs = current_thread_info()->fpregs;
unsigned long fprs;
int err = 0;
fprs = current_thread_info()->fpsaved[0];
if (fprs & FPRS_DL)
err |= copy_to_user(&fpu->si_float_regs[0], fpregs,
(sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_to_user(&fpu->si_float_regs[32], fpregs+16,
(sizeof(unsigned int) * 32));
err |= __put_user(current_thread_info()->xfsr[0], &fpu->si_fsr);
err |= __put_user(current_thread_info()->gsr[0], &fpu->si_gsr);
err |= __put_user(fprs, &fpu->si_fprs);
return err;
}
static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
int signo, sigset_t *oldset)
{
struct signal_frame32 __user *sf;
int sigframe_size;
u32 psr;
int i, err;
unsigned int seta[_COMPAT_NSIG_WORDS];
/* 1. Make sure everything is clean */
synchronize_user_stack();
save_and_clear_fpu();
sigframe_size = SF_ALIGNEDSZ;
if (!(current_thread_info()->fpsaved[0] & FPRS_FEF))
sigframe_size -= sizeof(__siginfo_fpu_t);
sf = (struct signal_frame32 __user *)
get_sigframe(&ka->sa, regs, sigframe_size);
if (invalid_frame_pointer(sf, sigframe_size))
goto sigill;
if (get_thread_wsaved() != 0)
goto sigill;
/* 2. Save the current process state */
if (test_thread_flag(TIF_32BIT)) {
regs->tpc &= 0xffffffff;
regs->tnpc &= 0xffffffff;
}
err = put_user(regs->tpc, &sf->info.si_regs.pc);
err |= __put_user(regs->tnpc, &sf->info.si_regs.npc);
err |= __put_user(regs->y, &sf->info.si_regs.y);
psr = tstate_to_psr(regs->tstate);
if (current_thread_info()->fpsaved[0] & FPRS_FEF)
psr |= PSR_EF;
err |= __put_user(psr, &sf->info.si_regs.psr);
for (i = 0; i < 16; i++)
err |= __put_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
for (i = 1; i < 16; i++)
err |= __put_user(((u32 *)regs->u_regs)[2*i],
&sf->v8plus.g_upper[i]);
err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
&sf->v8plus.asi);
if (psr & PSR_EF) {
err |= save_fpu_state32(regs, &sf->fpu_state);
err |= __put_user((u64)&sf->fpu_state, &sf->fpu_save);
} else {
err |= __put_user(0, &sf->fpu_save);
}
switch (_NSIG_WORDS) {
case 4: seta[7] = (oldset->sig[3] >> 32);
seta[6] = oldset->sig[3];
case 3: seta[5] = (oldset->sig[2] >> 32);
seta[4] = oldset->sig[2];
case 2: seta[3] = (oldset->sig[1] >> 32);
seta[2] = oldset->sig[1];
case 1: seta[1] = (oldset->sig[0] >> 32);
seta[0] = oldset->sig[0];
}
err |= __put_user(seta[0], &sf->info.si_mask);
err |= __copy_to_user(sf->extramask, seta + 1,
(_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
err |= copy_in_user((u32 __user *)sf,
(u32 __user *)(regs->u_regs[UREG_FP]),
sizeof(struct reg_window32));
if (err)
goto sigsegv;
/* 3. signal handler back-trampoline and parameters */
regs->u_regs[UREG_FP] = (unsigned long) sf;
regs->u_regs[UREG_I0] = signo;
regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
/* 4. signal handler */
regs->tpc = (unsigned long) ka->sa.sa_handler;
regs->tnpc = (regs->tpc + 4);
if (test_thread_flag(TIF_32BIT)) {
regs->tpc &= 0xffffffff;
regs->tnpc &= 0xffffffff;
}
/* 5. return to kernel instructions */
if (ka->ka_restorer) {
regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
} else {
/* Flush instruction space. */
unsigned long address = ((unsigned long)&(sf->insns[0]));
pgd_t *pgdp = pgd_offset(current->mm, address);
pud_t *pudp = pud_offset(pgdp, address);
pmd_t *pmdp = pmd_offset(pudp, address);
pte_t *ptep;
pte_t pte;
regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
err = __put_user(0x821020d8, &sf->insns[0]); /*mov __NR_sigreturn, %g1*/
err |= __put_user(0x91d02010, &sf->insns[1]); /*t 0x10*/
if (err)
goto sigsegv;
preempt_disable();
ptep = pte_offset_map(pmdp, address);
pte = *ptep;
if (pte_present(pte)) {
unsigned long page = (unsigned long)
page_address(pte_page(pte));
wmb();
__asm__ __volatile__("flush %0 + %1"
: /* no outputs */
: "r" (page),
"r" (address & (PAGE_SIZE - 1))
: "memory");
}
pte_unmap(ptep);
preempt_enable();
}
return;
sigill:
do_exit(SIGILL);
sigsegv:
force_sigsegv(signo, current);
}
static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
unsigned long signr, sigset_t *oldset,
siginfo_t *info)
{
struct rt_signal_frame32 __user *sf;
int sigframe_size;
u32 psr;
int i, err;
compat_sigset_t seta;
/* 1. Make sure everything is clean */
synchronize_user_stack();
save_and_clear_fpu();
sigframe_size = RT_ALIGNEDSZ;
if (!(current_thread_info()->fpsaved[0] & FPRS_FEF))
sigframe_size -= sizeof(__siginfo_fpu_t);
sf = (struct rt_signal_frame32 __user *)
get_sigframe(&ka->sa, regs, sigframe_size);
if (invalid_frame_pointer(sf, sigframe_size))
goto sigill;
if (get_thread_wsaved() != 0)
goto sigill;
/* 2. Save the current process state */
if (test_thread_flag(TIF_32BIT)) {
regs->tpc &= 0xffffffff;
regs->tnpc &= 0xffffffff;
}
err = put_user(regs->tpc, &sf->regs.pc);
err |= __put_user(regs->tnpc, &sf->regs.npc);
err |= __put_user(regs->y, &sf->regs.y);
psr = tstate_to_psr(regs->tstate);
if (current_thread_info()->fpsaved[0] & FPRS_FEF)
psr |= PSR_EF;
err |= __put_user(psr, &sf->regs.psr);
for (i = 0; i < 16; i++)
err |= __put_user(regs->u_regs[i], &sf->regs.u_regs[i]);
err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
for (i = 1; i < 16; i++)
err |= __put_user(((u32 *)regs->u_regs)[2*i],
&sf->v8plus.g_upper[i]);
err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
&sf->v8plus.asi);
if (psr & PSR_EF) {
err |= save_fpu_state32(regs, &sf->fpu_state);
err |= __put_user((u64)&sf->fpu_state, &sf->fpu_save);
} else {
err |= __put_user(0, &sf->fpu_save);
}
/* Update the siginfo structure. */
err |= copy_siginfo_to_user32(&sf->info, info);
/* Setup sigaltstack */
err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
switch (_NSIG_WORDS) {
case 4: seta.sig[7] = (oldset->sig[3] >> 32);
seta.sig[6] = oldset->sig[3];
case 3: seta.sig[5] = (oldset->sig[2] >> 32);
seta.sig[4] = oldset->sig[2];
case 2: seta.sig[3] = (oldset->sig[1] >> 32);
seta.sig[2] = oldset->sig[1];
case 1: seta.sig[1] = (oldset->sig[0] >> 32);
seta.sig[0] = oldset->sig[0];
}
err |= __copy_to_user(&sf->mask, &seta, sizeof(compat_sigset_t));
err |= copy_in_user((u32 __user *)sf,
(u32 __user *)(regs->u_regs[UREG_FP]),
sizeof(struct reg_window32));
if (err)
goto sigsegv;
/* 3. signal handler back-trampoline and parameters */
regs->u_regs[UREG_FP] = (unsigned long) sf;
regs->u_regs[UREG_I0] = signr;
regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
/* 4. signal handler */
regs->tpc = (unsigned long) ka->sa.sa_handler;
regs->tnpc = (regs->tpc + 4);
if (test_thread_flag(TIF_32BIT)) {
regs->tpc &= 0xffffffff;
regs->tnpc &= 0xffffffff;
}
/* 5. return to kernel instructions */
if (ka->ka_restorer)
regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
else {
/* Flush instruction space. */
unsigned long address = ((unsigned long)&(sf->insns[0]));
pgd_t *pgdp = pgd_offset(current->mm, address);
pud_t *pudp = pud_offset(pgdp, address);
pmd_t *pmdp = pmd_offset(pudp, address);
pte_t *ptep;
regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
/* mov __NR_rt_sigreturn, %g1 */
err |= __put_user(0x82102065, &sf->insns[0]);
/* t 0x10 */
err |= __put_user(0x91d02010, &sf->insns[1]);
if (err)
goto sigsegv;
preempt_disable();
ptep = pte_offset_map(pmdp, address);
if (pte_present(*ptep)) {
unsigned long page = (unsigned long)
page_address(pte_page(*ptep));
wmb();
__asm__ __volatile__("flush %0 + %1"
: /* no outputs */
: "r" (page),
"r" (address & (PAGE_SIZE - 1))
: "memory");
}
pte_unmap(ptep);
preempt_enable();
}
return;
sigill:
do_exit(SIGILL);
sigsegv:
force_sigsegv(signr, current);
}
static inline void handle_signal32(unsigned long signr, struct k_sigaction *ka,
siginfo_t *info,
sigset_t *oldset, struct pt_regs *regs)
{
if (ka->sa.sa_flags & SA_SIGINFO)
setup_rt_frame32(ka, regs, signr, oldset, info);
else
setup_frame32(ka, regs, signr, oldset);
spin_lock_irq(&current->sighand->siglock);
sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NOMASK))
sigaddset(&current->blocked,signr);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
}
static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
struct sigaction *sa)
{
switch (regs->u_regs[UREG_I0]) {
case ERESTART_RESTARTBLOCK:
case ERESTARTNOHAND:
no_system_call_restart:
regs->u_regs[UREG_I0] = EINTR;
regs->tstate |= TSTATE_ICARRY;
break;
case ERESTARTSYS:
if (!(sa->sa_flags & SA_RESTART))
goto no_system_call_restart;
/* fallthrough */
case ERESTARTNOINTR:
regs->u_regs[UREG_I0] = orig_i0;
regs->tpc -= 4;
regs->tnpc -= 4;
}
}
/* 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.
*/
void do_signal32(sigset_t *oldset, struct pt_regs * regs,
int restart_syscall, unsigned long orig_i0)
{
struct k_sigaction ka;
siginfo_t info;
int signr;
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
/* If the debugger messes with the program counter, it clears
* the "in syscall" bit, directing us to not perform a syscall
* restart.
*/
if (restart_syscall && !pt_regs_is_syscall(regs))
restart_syscall = 0;
if (signr > 0) {
if (restart_syscall)
syscall_restart32(orig_i0, regs, &ka.sa);
handle_signal32(signr, &ka, &info, oldset, regs);
/* a signal was successfully delivered; the saved
* sigmask will have been stored in the signal frame,
* and will be restored by sigreturn, so we can simply
* clear the TIF_RESTORE_SIGMASK flag.
*/
if (test_thread_flag(TIF_RESTORE_SIGMASK))
clear_thread_flag(TIF_RESTORE_SIGMASK);
return;
}
if (restart_syscall &&
(regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
regs->u_regs[UREG_I0] == ERESTARTSYS ||
regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
/* replay the system call when we are done */
regs->u_regs[UREG_I0] = orig_i0;
regs->tpc -= 4;
regs->tnpc -= 4;
}
if (restart_syscall &&
regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
regs->u_regs[UREG_G1] = __NR_restart_syscall;
regs->tpc -= 4;
regs->tnpc -= 4;
}
/* if there's no signal to deliver, we just put the saved sigmask
* back
*/
if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
clear_thread_flag(TIF_RESTORE_SIGMASK);
sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
}
}
struct sigstack32 {
u32 the_stack;
int cur_status;
};
asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
{
struct sigstack32 __user *ssptr =
(struct sigstack32 __user *)((unsigned long)(u_ssptr));
struct sigstack32 __user *ossptr =
(struct sigstack32 __user *)((unsigned long)(u_ossptr));
int ret = -EFAULT;
/* First see if old state is wanted. */
if (ossptr) {
if (put_user(current->sas_ss_sp + current->sas_ss_size,
&ossptr->the_stack) ||
__put_user(on_sig_stack(sp), &ossptr->cur_status))
goto out;
}
/* Now see if we want to update the new state. */
if (ssptr) {
u32 ss_sp;
if (get_user(ss_sp, &ssptr->the_stack))
goto out;
/* If the current stack was set with sigaltstack, don't
* swap stacks while we are on it.
*/
ret = -EPERM;
if (current->sas_ss_sp && on_sig_stack(sp))
goto out;
/* Since we don't know the extent of the stack, and we don't
* track onstack-ness, but rather calculate it, we must
* presume a size. Ho hum this interface is lossy.
*/
current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
current->sas_ss_size = SIGSTKSZ;
}
ret = 0;
out:
return ret;
}
asmlinkage long do_sys32_sigaltstack(u32 ussa, u32 uossa, unsigned long sp)
{
stack_t uss, uoss;
u32 u_ss_sp = 0;
int ret;
mm_segment_t old_fs;
stack_t32 __user *uss32 = compat_ptr(ussa);
stack_t32 __user *uoss32 = compat_ptr(uossa);
if (ussa && (get_user(u_ss_sp, &uss32->ss_sp) ||
__get_user(uss.ss_flags, &uss32->ss_flags) ||
__get_user(uss.ss_size, &uss32->ss_size)))
return -EFAULT;
uss.ss_sp = compat_ptr(u_ss_sp);
old_fs = get_fs();
set_fs(KERNEL_DS);
ret = do_sigaltstack(ussa ? (stack_t __user *) &uss : NULL,
uossa ? (stack_t __user *) &uoss : NULL, sp);
set_fs(old_fs);
if (!ret && uossa && (put_user(ptr_to_compat(uoss.ss_sp), &uoss32->ss_sp) ||
__put_user(uoss.ss_flags, &uoss32->ss_flags) ||
__put_user(uoss.ss_size, &uoss32->ss_size)))
return -EFAULT;
return ret;
}
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