CRIS v10: correct do_signal to fix oops and clean up signal handling in general
This fixes a kernel panic on boot due to do_signal not being compatible with it's callers. - do_signal now returns void, and does not have the previous signal set as a parameter. - Remove sys_rt_sigsuspend, we can use the common one instead. - Change sys_sigsuspend to be more like x86, don't call do_signal here. - handle_signal, setup_frame and setup_rt_frame now return -EFAULT if we've delivered a segfault, which is used by callers to perform necessary cleanup. - Break long lines, correct whitespace and formatting errors. Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Mikael Starvik <mikael.starvik@axis.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
3ea0345be3
commit
a4858d4dab
|
@ -7,7 +7,7 @@
|
|||
*
|
||||
* Ideas also taken from arch/arm.
|
||||
*
|
||||
* Copyright (C) 2000, 2001 Axis Communications AB
|
||||
* Copyright (C) 2000-2007 Axis Communications AB
|
||||
*
|
||||
* Authors: Bjorn Wesen (bjornw@axis.com)
|
||||
*
|
||||
|
@ -40,84 +40,30 @@
|
|||
*/
|
||||
#define RESTART_CRIS_SYS(regs) regs->r10 = regs->orig_r10; regs->irp -= 2;
|
||||
|
||||
int do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs);
|
||||
void do_signal(int canrestart, struct pt_regs *regs);
|
||||
|
||||
/*
|
||||
* Atomically swap in the new signal mask, and wait for a signal. Define
|
||||
* Atomically swap in the new signal mask, and wait for a signal. Define
|
||||
* dummy arguments to be able to reach the regs argument. (Note that this
|
||||
* arrangement relies on old_sigset_t occupying one register.)
|
||||
*/
|
||||
int
|
||||
sys_sigsuspend(old_sigset_t mask, long r11, long r12, long r13, long mof,
|
||||
long srp, struct pt_regs *regs)
|
||||
int sys_sigsuspend(old_sigset_t mask, long r11, long r12, long r13, long mof,
|
||||
long srp, struct pt_regs *regs)
|
||||
{
|
||||
sigset_t saveset;
|
||||
|
||||
mask &= _BLOCKABLE;
|
||||
spin_lock_irq(¤t->sighand->siglock);
|
||||
saveset = current->blocked;
|
||||
current->saved_sigmask = current->blocked;
|
||||
siginitset(¤t->blocked, mask);
|
||||
recalc_sigpending();
|
||||
spin_unlock_irq(¤t->sighand->siglock);
|
||||
|
||||
regs->r10 = -EINTR;
|
||||
while (1) {
|
||||
current->state = TASK_INTERRUPTIBLE;
|
||||
schedule();
|
||||
if (do_signal(0, &saveset, regs))
|
||||
/* We will get here twice: once to call the signal
|
||||
handler, then again to return from the
|
||||
sigsuspend system call. When calling the
|
||||
signal handler, R10 holds the signal number as
|
||||
set through do_signal. The sigsuspend call
|
||||
will return with the restored value set above;
|
||||
always -EINTR. */
|
||||
return regs->r10;
|
||||
}
|
||||
current->state = TASK_INTERRUPTIBLE;
|
||||
schedule();
|
||||
set_thread_flag(TIF_RESTORE_SIGMASK);
|
||||
return -ERESTARTNOHAND;
|
||||
}
|
||||
|
||||
/* Define dummy arguments to be able to reach the regs argument. (Note that
|
||||
* this arrangement relies on size_t occupying one register.)
|
||||
*/
|
||||
int
|
||||
sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, long r12, long r13,
|
||||
long mof, long srp, struct pt_regs *regs)
|
||||
{
|
||||
sigset_t saveset, newset;
|
||||
|
||||
/* XXX: Don't preclude handling different sized sigset_t's. */
|
||||
if (sigsetsize != sizeof(sigset_t))
|
||||
return -EINVAL;
|
||||
|
||||
if (copy_from_user(&newset, unewset, sizeof(newset)))
|
||||
return -EFAULT;
|
||||
sigdelsetmask(&newset, ~_BLOCKABLE);
|
||||
|
||||
spin_lock_irq(¤t->sighand->siglock);
|
||||
saveset = current->blocked;
|
||||
current->blocked = newset;
|
||||
recalc_sigpending();
|
||||
spin_unlock_irq(¤t->sighand->siglock);
|
||||
|
||||
regs->r10 = -EINTR;
|
||||
while (1) {
|
||||
current->state = TASK_INTERRUPTIBLE;
|
||||
schedule();
|
||||
if (do_signal(0, &saveset, regs))
|
||||
/* We will get here twice: once to call the signal
|
||||
handler, then again to return from the
|
||||
sigsuspend system call. When calling the
|
||||
signal handler, R10 holds the signal number as
|
||||
set through do_signal. The sigsuspend call
|
||||
will return with the restored value set above;
|
||||
always -EINTR. */
|
||||
return regs->r10;
|
||||
}
|
||||
}
|
||||
|
||||
int
|
||||
sys_sigaction(int sig, const struct old_sigaction __user *act,
|
||||
struct old_sigaction *oact)
|
||||
int sys_sigaction(int sig, const struct old_sigaction __user *act,
|
||||
struct old_sigaction *oact)
|
||||
{
|
||||
struct k_sigaction new_ka, old_ka;
|
||||
int ret;
|
||||
|
@ -147,8 +93,7 @@ sys_sigaction(int sig, const struct old_sigaction __user *act,
|
|||
return ret;
|
||||
}
|
||||
|
||||
int
|
||||
sys_sigaltstack(const stack_t *uss, stack_t __user *uoss)
|
||||
int sys_sigaltstack(const stack_t *uss, stack_t __user *uoss)
|
||||
{
|
||||
return do_sigaltstack(uss, uoss, rdusp());
|
||||
}
|
||||
|
@ -205,7 +150,7 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
|
|||
|
||||
/* TODO: the other ports use regs->orig_XX to disable syscall checks
|
||||
* after this completes, but we don't use that mechanism. maybe we can
|
||||
* use it now ?
|
||||
* use it now ?
|
||||
*/
|
||||
|
||||
return err;
|
||||
|
@ -216,7 +161,7 @@ badframe:
|
|||
|
||||
/* Define dummy arguments to be able to reach the regs argument. */
|
||||
|
||||
asmlinkage int sys_sigreturn(long r10, long r11, long r12, long r13, long mof,
|
||||
asmlinkage int sys_sigreturn(long r10, long r11, long r12, long r13, long mof,
|
||||
long srp, struct pt_regs *regs)
|
||||
{
|
||||
struct sigframe __user *frame = (struct sigframe *)rdusp();
|
||||
|
@ -243,7 +188,7 @@ asmlinkage int sys_sigreturn(long r10, long r11, long r12, long r13, long mof,
|
|||
current->blocked = set;
|
||||
recalc_sigpending();
|
||||
spin_unlock_irq(¤t->sighand->siglock);
|
||||
|
||||
|
||||
if (restore_sigcontext(regs, &frame->sc))
|
||||
goto badframe;
|
||||
|
||||
|
@ -254,11 +199,11 @@ asmlinkage int sys_sigreturn(long r10, long r11, long r12, long r13, long mof,
|
|||
badframe:
|
||||
force_sig(SIGSEGV, current);
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
/* Define dummy arguments to be able to reach the regs argument. */
|
||||
|
||||
asmlinkage int sys_rt_sigreturn(long r10, long r11, long r12, long r13,
|
||||
asmlinkage int sys_rt_sigreturn(long r10, long r11, long r12, long r13,
|
||||
long mof, long srp, struct pt_regs *regs)
|
||||
{
|
||||
struct rt_sigframe __user *frame = (struct rt_sigframe *)rdusp();
|
||||
|
@ -282,7 +227,7 @@ asmlinkage int sys_rt_sigreturn(long r10, long r11, long r12, long r13,
|
|||
current->blocked = set;
|
||||
recalc_sigpending();
|
||||
spin_unlock_irq(¤t->sighand->siglock);
|
||||
|
||||
|
||||
if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
|
||||
goto badframe;
|
||||
|
||||
|
@ -294,14 +239,14 @@ asmlinkage int sys_rt_sigreturn(long r10, long r11, long r12, long r13,
|
|||
badframe:
|
||||
force_sig(SIGSEGV, current);
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Set up a signal frame.
|
||||
*/
|
||||
|
||||
static int
|
||||
setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, unsigned long mask)
|
||||
static int setup_sigcontext(struct sigcontext __user *sc,
|
||||
struct pt_regs *regs, unsigned long mask)
|
||||
{
|
||||
int err = 0;
|
||||
unsigned long usp = rdusp();
|
||||
|
@ -324,10 +269,11 @@ setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, unsigned lo
|
|||
return err;
|
||||
}
|
||||
|
||||
/* figure out where we want to put the new signal frame - usually on the stack */
|
||||
/* Figure out where we want to put the new signal frame
|
||||
* - usually on the stack. */
|
||||
|
||||
static inline void __user *
|
||||
get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
|
||||
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
|
||||
{
|
||||
unsigned long sp = rdusp();
|
||||
|
||||
|
@ -345,15 +291,15 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
|
|||
}
|
||||
|
||||
/* grab and setup a signal frame.
|
||||
*
|
||||
*
|
||||
* basically we stack a lot of state info, and arrange for the
|
||||
* user-mode program to return to the kernel using either a
|
||||
* trampoline which performs the syscall sigreturn, or a provided
|
||||
* user-mode trampoline.
|
||||
*/
|
||||
|
||||
static void setup_frame(int sig, struct k_sigaction *ka,
|
||||
sigset_t *set, struct pt_regs * regs)
|
||||
static int setup_frame(int sig, struct k_sigaction *ka,
|
||||
sigset_t *set, struct pt_regs *regs)
|
||||
{
|
||||
struct sigframe __user *frame;
|
||||
unsigned long return_ip;
|
||||
|
@ -401,14 +347,15 @@ static void setup_frame(int sig, struct k_sigaction *ka,
|
|||
|
||||
wrusp((unsigned long)frame);
|
||||
|
||||
return;
|
||||
return 0;
|
||||
|
||||
give_sigsegv:
|
||||
force_sigsegv(sig, current);
|
||||
return -EFAULT;
|
||||
}
|
||||
|
||||
static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
|
||||
sigset_t *set, struct pt_regs * regs)
|
||||
static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
|
||||
sigset_t *set, struct pt_regs *regs)
|
||||
{
|
||||
struct rt_sigframe __user *frame;
|
||||
unsigned long return_ip;
|
||||
|
@ -443,9 +390,10 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
|
|||
/* trampoline - the desired return ip is the retcode itself */
|
||||
return_ip = (unsigned long)&frame->retcode;
|
||||
/* This is movu.w __NR_rt_sigreturn, r9; break 13; */
|
||||
err |= __put_user(0x9c5f, (short __user*)(frame->retcode+0));
|
||||
err |= __put_user(__NR_rt_sigreturn, (short __user*)(frame->retcode+2));
|
||||
err |= __put_user(0xe93d, (short __user*)(frame->retcode+4));
|
||||
err |= __put_user(0x9c5f, (short __user *)(frame->retcode+0));
|
||||
err |= __put_user(__NR_rt_sigreturn,
|
||||
(short __user *)(frame->retcode+2));
|
||||
err |= __put_user(0xe93d, (short __user *)(frame->retcode+4));
|
||||
}
|
||||
|
||||
if (err)
|
||||
|
@ -455,73 +403,81 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
|
|||
|
||||
/* Set up registers for signal handler */
|
||||
|
||||
regs->irp = (unsigned long) ka->sa.sa_handler; /* what we enter NOW */
|
||||
regs->srp = return_ip; /* what we enter LATER */
|
||||
regs->r10 = sig; /* first argument is signo */
|
||||
regs->r11 = (unsigned long) &frame->info; /* second argument is (siginfo_t *) */
|
||||
regs->r12 = 0; /* third argument is unused */
|
||||
|
||||
/* actually move the usp to reflect the stacked frame */
|
||||
/* What we enter NOW */
|
||||
regs->irp = (unsigned long) ka->sa.sa_handler;
|
||||
/* What we enter LATER */
|
||||
regs->srp = return_ip;
|
||||
/* First argument is signo */
|
||||
regs->r10 = sig;
|
||||
/* Second argument is (siginfo_t *) */
|
||||
regs->r11 = (unsigned long)&frame->info;
|
||||
/* Third argument is unused */
|
||||
regs->r12 = 0;
|
||||
|
||||
/* Actually move the usp to reflect the stacked frame */
|
||||
wrusp((unsigned long)frame);
|
||||
|
||||
return;
|
||||
return 0;
|
||||
|
||||
give_sigsegv:
|
||||
force_sigsegv(sig, current);
|
||||
return -EFAULT;
|
||||
}
|
||||
|
||||
/*
|
||||
* OK, we're invoking a handler
|
||||
*/
|
||||
*/
|
||||
|
||||
static inline void
|
||||
handle_signal(int canrestart, unsigned long sig,
|
||||
siginfo_t *info, struct k_sigaction *ka,
|
||||
sigset_t *oldset, struct pt_regs * regs)
|
||||
static inline int handle_signal(int canrestart, unsigned long sig,
|
||||
siginfo_t *info, struct k_sigaction *ka,
|
||||
sigset_t *oldset, struct pt_regs *regs)
|
||||
{
|
||||
int ret;
|
||||
|
||||
/* Are we from a system call? */
|
||||
if (canrestart) {
|
||||
/* If so, check system call restarting.. */
|
||||
switch (regs->r10) {
|
||||
case -ERESTART_RESTARTBLOCK:
|
||||
case -ERESTARTNOHAND:
|
||||
/* ERESTARTNOHAND means that the syscall should only be
|
||||
restarted if there was no handler for the signal, and since
|
||||
we only get here if there is a handler, we don't restart */
|
||||
case -ERESTART_RESTARTBLOCK:
|
||||
case -ERESTARTNOHAND:
|
||||
/* ERESTARTNOHAND means that the syscall should
|
||||
* only be restarted if there was no handler for
|
||||
* the signal, and since we only get here if there
|
||||
* is a handler, we don't restart */
|
||||
regs->r10 = -EINTR;
|
||||
break;
|
||||
case -ERESTARTSYS:
|
||||
/* ERESTARTSYS means to restart the syscall if
|
||||
* there is no handler or the handler was
|
||||
* registered with SA_RESTART */
|
||||
if (!(ka->sa.sa_flags & SA_RESTART)) {
|
||||
regs->r10 = -EINTR;
|
||||
break;
|
||||
|
||||
case -ERESTARTSYS:
|
||||
/* ERESTARTSYS means to restart the syscall if there is no
|
||||
handler or the handler was registered with SA_RESTART */
|
||||
if (!(ka->sa.sa_flags & SA_RESTART)) {
|
||||
regs->r10 = -EINTR;
|
||||
break;
|
||||
}
|
||||
/* fallthrough */
|
||||
case -ERESTARTNOINTR:
|
||||
/* ERESTARTNOINTR means that the syscall should be called again
|
||||
after the signal handler returns. */
|
||||
RESTART_CRIS_SYS(regs);
|
||||
}
|
||||
/* fallthrough */
|
||||
case -ERESTARTNOINTR:
|
||||
/* ERESTARTNOINTR means that the syscall should
|
||||
* be called again after the signal handler returns. */
|
||||
RESTART_CRIS_SYS(regs);
|
||||
}
|
||||
}
|
||||
|
||||
/* Set up the stack frame */
|
||||
if (ka->sa.sa_flags & SA_SIGINFO)
|
||||
setup_rt_frame(sig, ka, info, oldset, regs);
|
||||
ret = setup_rt_frame(sig, ka, info, oldset, regs);
|
||||
else
|
||||
setup_frame(sig, ka, oldset, regs);
|
||||
ret = setup_frame(sig, ka, oldset, regs);
|
||||
|
||||
if (ka->sa.sa_flags & SA_ONESHOT)
|
||||
ka->sa.sa_handler = SIG_DFL;
|
||||
|
||||
spin_lock_irq(¤t->sighand->siglock);
|
||||
sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
|
||||
if (!(ka->sa.sa_flags & SA_NODEFER))
|
||||
sigaddset(¤t->blocked,sig);
|
||||
recalc_sigpending();
|
||||
spin_unlock_irq(¤t->sighand->siglock);
|
||||
if (ret == 0) {
|
||||
spin_lock_irq(¤t->sighand->siglock);
|
||||
sigorsets(¤t->blocked, ¤t->blocked,
|
||||
&ka->sa.sa_mask);
|
||||
if (!(ka->sa.sa_flags & SA_NODEFER))
|
||||
sigaddset(¤t->blocked, sig);
|
||||
recalc_sigpending();
|
||||
spin_unlock_irq(¤t->sighand->siglock);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
|
@ -536,11 +492,12 @@ handle_signal(int canrestart, unsigned long sig,
|
|||
* mode below.
|
||||
*/
|
||||
|
||||
int do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs)
|
||||
void do_signal(int canrestart, struct pt_regs *regs)
|
||||
{
|
||||
siginfo_t info;
|
||||
int signr;
|
||||
struct k_sigaction ka;
|
||||
sigset_t *oldset;
|
||||
|
||||
/*
|
||||
* We want the common case to go fast, which
|
||||
|
@ -549,16 +506,26 @@ int do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs)
|
|||
* if so.
|
||||
*/
|
||||
if (!user_mode(regs))
|
||||
return 1;
|
||||
return;
|
||||
|
||||
if (!oldset)
|
||||
if (test_thread_flag(TIF_RESTORE_SIGMASK))
|
||||
oldset = ¤t->saved_sigmask;
|
||||
else
|
||||
oldset = ¤t->blocked;
|
||||
|
||||
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
|
||||
if (signr > 0) {
|
||||
/* Whee! Actually deliver the signal. */
|
||||
handle_signal(canrestart, signr, &info, &ka, oldset, regs);
|
||||
return 1;
|
||||
if (handle_signal(canrestart, signr, &info, &ka,
|
||||
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;
|
||||
}
|
||||
|
||||
/* Did we come from a system call? */
|
||||
|
@ -569,10 +536,16 @@ int do_signal(int canrestart, sigset_t *oldset, struct pt_regs *regs)
|
|||
regs->r10 == -ERESTARTNOINTR) {
|
||||
RESTART_CRIS_SYS(regs);
|
||||
}
|
||||
if (regs->r10 == -ERESTART_RESTARTBLOCK){
|
||||
if (regs->r10 == -ERESTART_RESTARTBLOCK) {
|
||||
regs->r10 = __NR_restart_syscall;
|
||||
regs->irp -= 2;
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
|
||||
/* 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, ¤t->saved_sigmask, NULL);
|
||||
}
|
||||
}
|
||||
|
|
Loading…
Reference in a new issue