Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

Pull signal handling cleanups from Al Viro:
 "This is the first pile; another one will come a bit later and will
  contain SYSCALL_DEFINE-related patches.

   - a bunch of signal-related syscalls (both native and compat)
     unified.

   - a bunch of compat syscalls switched to COMPAT_SYSCALL_DEFINE
     (fixing several potential problems with missing argument
     validation, while we are at it)

   - a lot of now-pointless wrappers killed

   - a couple of architectures (cris and hexagon) forgot to save
     altstack settings into sigframe, even though they used the
     (uninitialized) values in sigreturn; fixed.

   - microblaze fixes for delivery of multiple signals arriving at once

   - saner set of helpers for signal delivery introduced, several
     architectures switched to using those."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (143 commits)
  x86: convert to ksignal
  sparc: convert to ksignal
  arm: switch to struct ksignal * passing
  alpha: pass k_sigaction and siginfo_t using ksignal pointer
  burying unused conditionals
  make do_sigaltstack() static
  arm64: switch to generic old sigaction() (compat-only)
  arm64: switch to generic compat rt_sigaction()
  arm64: switch compat to generic old sigsuspend
  arm64: switch to generic compat rt_sigqueueinfo()
  arm64: switch to generic compat rt_sigpending()
  arm64: switch to generic compat rt_sigprocmask()
  arm64: switch to generic sigaltstack
  sparc: switch to generic old sigsuspend
  sparc: COMPAT_SYSCALL_DEFINE does all sign-extension as well as SYSCALL_DEFINE
  sparc: kill sign-extending wrappers for native syscalls
  kill sparc32_open()
  sparc: switch to use of generic old sigaction
  sparc: switch sys_compat_rt_sigaction() to COMPAT_SYSCALL_DEFINE
  mips: switch to generic sys_fork() and sys_clone()
  ...

1 files changed, 46 insertions, 96 deletions

diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
index 689e1ba62809..35923e8abd82 100644
--- a/arch/sparc/kernel/signal_64.c
+++ b/arch/sparc/kernel/signal_64.c
@@ -236,23 +236,6 @@ struct rt_signal_frame {
 	__siginfo_rwin_t	*rwin_save;
 };
 
-static long _sigpause_common(old_sigset_t set)
-{
-	sigset_t blocked;
-	siginitset(&blocked, set);
-	return sigsuspend(&blocked);
-}
-
-asmlinkage long sys_sigpause(unsigned int set)
-{
-	return _sigpause_common(set);
-}
-
-asmlinkage long sys_sigsuspend(old_sigset_t set)
-{
-	return _sigpause_common(set);
-}
-
 void do_rt_sigreturn(struct pt_regs *regs)
 {
 	struct rt_signal_frame __user *sf;
@@ -295,7 +278,8 @@ void do_rt_sigreturn(struct pt_regs *regs)
 		err |= restore_fpu_state(regs, fpu_save);
 
 	err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
-	if (err || do_sigaltstack(&sf->stack, NULL, (unsigned long)sf) == -EFAULT)
+	err |= restore_altstack(&sf->stack);
+	if (err)
 		goto segv;
 
 	err |= __get_user(rwin_save, &sf->rwin_save);
@@ -324,7 +308,7 @@ static int invalid_frame_pointer(void __user *fp)
 	return 0;
 }
 
-static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, unsigned long framesize)
+static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
 {
 	unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
 
@@ -336,12 +320,7 @@ static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *
 		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 -= framesize;
+	sp = sigsp(sp, ksig) - framesize;
 
 	/* Always align the stack frame.  This handles two cases.  First,
 	 * sigaltstack need not be mindful of platform specific stack
@@ -355,8 +334,7 @@ static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *
 }
 
 static inline int
-setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
-	       int signo, sigset_t *oldset, siginfo_t *info)
+setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
 {
 	struct rt_signal_frame __user *sf;
 	int wsaved, err, sf_size;
@@ -374,10 +352,12 @@ setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
 	if (wsaved)
 		sf_size += sizeof(__siginfo_rwin_t);
 	sf = (struct rt_signal_frame __user *)
-		get_sigframe(ka, regs, sf_size);
+		get_sigframe(ksig, regs, sf_size);
 
-	if (invalid_frame_pointer (sf))
-		goto sigill;
+	if (invalid_frame_pointer (sf)) {
+		do_exit(SIGILL);	/* won't return, actually */
+		return -EINVAL;
+	}
 
 	tail = (sf + 1);
 
@@ -403,11 +383,9 @@ setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
 	}
 	
 	/* 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);
+	err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 
-	err |= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));
+	err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
 
 	if (!wsaved) {
 		err |= copy_in_user((u64 __user *)sf,
@@ -420,18 +398,18 @@ setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
 		rp = &current_thread_info()->reg_window[wsaved - 1];
 		err |= copy_to_user(sf, rp, sizeof(struct reg_window));
 	}
-	if (info)
-		err |= copy_siginfo_to_user(&sf->info, info);
+	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+		err |= copy_siginfo_to_user(&sf->info, &ksig->info);
 	else {
-		err |= __put_user(signo, &sf->info.si_signo);
+		err |= __put_user(ksig->sig, &sf->info.si_signo);
 		err |= __put_user(SI_NOINFO, &sf->info.si_code);
 	}
 	if (err)
-		goto sigsegv;
+		return err;
 	
 	/* 3. signal handler back-trampoline and parameters */
 	regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
-	regs->u_regs[UREG_I0] = signo;
+	regs->u_regs[UREG_I0] = ksig->sig;
 	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 
 	/* The sigcontext is passed in this way because of how it
@@ -441,37 +419,15 @@ setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
 	regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
 
 	/* 5. signal handler */
-	regs->tpc = (unsigned long) ka->sa.sa_handler;
+	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 	regs->tnpc = (regs->tpc + 4);
 	if (test_thread_flag(TIF_32BIT)) {
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
 	/* 4. return to kernel instructions */
-	regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
+	regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 	return 0;
-
-sigill:
-	do_exit(SIGILL);
-	return -EINVAL;
-
-sigsegv:
-	force_sigsegv(signo, current);
-	return -EFAULT;
-}
-
-static inline void handle_signal(unsigned long signr, struct k_sigaction *ka,
-				siginfo_t *info,
-				sigset_t *oldset, struct pt_regs *regs)
-{
-	int err;
-
-	err = setup_rt_frame(ka, regs, signr, oldset,
-			     (ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
-	if (err)
-		return;
-
-	signal_delivered(signr, info, ka, regs, 0);
 }
 
 static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
@@ -501,11 +457,9 @@ static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
  */
 static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 {
-	struct k_sigaction ka;
+	struct ksignal ksig;
 	int restart_syscall;
-	sigset_t *oldset = sigmask_to_save();
-	siginfo_t info;
-	int signr;
+	bool has_handler;
 	
 	/* It's a lot of work and synchronization to add a new ptrace
 	 * register for GDB to save and restore in order to get
@@ -531,13 +485,13 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 
 #ifdef CONFIG_COMPAT
 	if (test_thread_flag(TIF_32BIT)) {
-		extern void do_signal32(sigset_t *, struct pt_regs *);
-		do_signal32(oldset, regs);
+		extern void do_signal32(struct pt_regs *);
+		do_signal32(regs);
 		return;
 	}
 #endif	
 
-	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+	has_handler = get_signal(&ksig);
 
 	restart_syscall = 0;
 	if (pt_regs_is_syscall(regs) &&
@@ -546,34 +500,30 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 		orig_i0 = regs->u_regs[UREG_G6];
 	}
 
-	if (signr > 0) {
+	if (has_handler) {
 		if (restart_syscall)
-			syscall_restart(orig_i0, regs, &ka.sa);
-		handle_signal(signr, &ka, &info, oldset, regs);
-		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;
-		pt_regs_clear_syscall(regs);
-	}
-	if (restart_syscall &&
-	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
-		regs->u_regs[UREG_G1] = __NR_restart_syscall;
-		regs->tpc -= 4;
-		regs->tnpc -= 4;
-		pt_regs_clear_syscall(regs);
+			syscall_restart(orig_i0, regs, &ksig.ka.sa);
+		signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
+	} else {
+		if (restart_syscall) {
+			switch (regs->u_regs[UREG_I0]) {
+			case ERESTARTNOHAND:
+	     		case ERESTARTSYS:
+			case ERESTARTNOINTR:
+				/* replay the system call when we are done */
+				regs->u_regs[UREG_I0] = orig_i0;
+				regs->tpc -= 4;
+				regs->tnpc -= 4;
+				pt_regs_clear_syscall(regs);
+			case ERESTART_RESTARTBLOCK:
+				regs->u_regs[UREG_G1] = __NR_restart_syscall;
+				regs->tpc -= 4;
+				regs->tnpc -= 4;
+				pt_regs_clear_syscall(regs);
+			}
+		}
+		restore_saved_sigmask();
 	}
-
-	/* If there's no signal to deliver, we just put the saved sigmask
-	 * back
-	 */
-	restore_saved_sigmask();
 }
 
 void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)