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, 60 insertions, 124 deletions

diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index d6bf1f34a6e9..69562992e457 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -278,7 +278,7 @@ static const struct {
 };
 
 static int
-__setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
+__setup_frame(int sig, struct ksignal *ksig, sigset_t *set,
 	      struct pt_regs *regs)
 {
 	struct sigframe __user *frame;
@@ -286,7 +286,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
 	int err = 0;
 	void __user *fpstate = NULL;
 
-	frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
+	frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate);
 
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		return -EFAULT;
@@ -307,8 +307,8 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
 		restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn);
 	else
 		restorer = &frame->retcode;
-	if (ka->sa.sa_flags & SA_RESTORER)
-		restorer = ka->sa.sa_restorer;
+	if (ksig->ka.sa.sa_flags & SA_RESTORER)
+		restorer = ksig->ka.sa.sa_restorer;
 
 	/* Set up to return from userspace.  */
 	err |= __put_user(restorer, &frame->pretcode);
@@ -327,7 +327,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
 
 	/* Set up registers for signal handler */
 	regs->sp = (unsigned long)frame;
-	regs->ip = (unsigned long)ka->sa.sa_handler;
+	regs->ip = (unsigned long)ksig->ka.sa.sa_handler;
 	regs->ax = (unsigned long)sig;
 	regs->dx = 0;
 	regs->cx = 0;
@@ -340,7 +340,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
 	return 0;
 }
 
-static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+static int __setup_rt_frame(int sig, struct ksignal *ksig,
 			    sigset_t *set, struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
@@ -348,7 +348,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	int err = 0;
 	void __user *fpstate = NULL;
 
-	frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
+	frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate);
 
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		return -EFAULT;
@@ -368,8 +368,8 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 
 		/* Set up to return from userspace.  */
 		restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
-		if (ka->sa.sa_flags & SA_RESTORER)
-			restorer = ka->sa.sa_restorer;
+		if (ksig->ka.sa.sa_flags & SA_RESTORER)
+			restorer = ksig->ka.sa.sa_restorer;
 		put_user_ex(restorer, &frame->pretcode);
 
 		/*
@@ -382,7 +382,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 		put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode);
 	} put_user_catch(err);
 	
-	err |= copy_siginfo_to_user(&frame->info, info);
+	err |= copy_siginfo_to_user(&frame->info, &ksig->info);
 	err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
 				regs, set->sig[0]);
 	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
@@ -392,7 +392,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 
 	/* Set up registers for signal handler */
 	regs->sp = (unsigned long)frame;
-	regs->ip = (unsigned long)ka->sa.sa_handler;
+	regs->ip = (unsigned long)ksig->ka.sa.sa_handler;
 	regs->ax = (unsigned long)sig;
 	regs->dx = (unsigned long)&frame->info;
 	regs->cx = (unsigned long)&frame->uc;
@@ -405,20 +405,20 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	return 0;
 }
 #else /* !CONFIG_X86_32 */
-static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+static int __setup_rt_frame(int sig, struct ksignal *ksig,
 			    sigset_t *set, struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
 	void __user *fp = NULL;
 	int err = 0;
 
-	frame = get_sigframe(ka, regs, sizeof(struct rt_sigframe), &fp);
+	frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp);
 
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		return -EFAULT;
 
-	if (ka->sa.sa_flags & SA_SIGINFO) {
-		if (copy_siginfo_to_user(&frame->info, info))
+	if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
+		if (copy_siginfo_to_user(&frame->info, &ksig->info))
 			return -EFAULT;
 	}
 
@@ -434,8 +434,8 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 		/* Set up to return from userspace.  If provided, use a stub
 		   already in userspace.  */
 		/* x86-64 should always use SA_RESTORER. */
-		if (ka->sa.sa_flags & SA_RESTORER) {
-			put_user_ex(ka->sa.sa_restorer, &frame->pretcode);
+		if (ksig->ka.sa.sa_flags & SA_RESTORER) {
+			put_user_ex(ksig->ka.sa.sa_restorer, &frame->pretcode);
 		} else {
 			/* could use a vstub here */
 			err |= -EFAULT;
@@ -457,7 +457,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	   next argument after the signal number on the stack. */
 	regs->si = (unsigned long)&frame->info;
 	regs->dx = (unsigned long)&frame->uc;
-	regs->ip = (unsigned long) ka->sa.sa_handler;
+	regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
 
 	regs->sp = (unsigned long)frame;
 
@@ -469,8 +469,8 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 }
 #endif /* CONFIG_X86_32 */
 
-static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
-			      siginfo_t *info, compat_sigset_t *set,
+static int x32_setup_rt_frame(struct ksignal *ksig,
+			      compat_sigset_t *set,
 			      struct pt_regs *regs)
 {
 #ifdef CONFIG_X86_X32_ABI
@@ -479,13 +479,13 @@ static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
 	int err = 0;
 	void __user *fpstate = NULL;
 
-	frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
+	frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate);
 
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		return -EFAULT;
 
-	if (ka->sa.sa_flags & SA_SIGINFO) {
-		if (copy_siginfo_to_user32(&frame->info, info))
+	if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
+		if (copy_siginfo_to_user32(&frame->info, &ksig->info))
 			return -EFAULT;
 	}
 
@@ -499,8 +499,8 @@ static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
 		err |= __compat_save_altstack(&frame->uc.uc_stack, regs->sp);
 		put_user_ex(0, &frame->uc.uc__pad0);
 
-		if (ka->sa.sa_flags & SA_RESTORER) {
-			restorer = ka->sa.sa_restorer;
+		if (ksig->ka.sa.sa_flags & SA_RESTORER) {
+			restorer = ksig->ka.sa.sa_restorer;
 		} else {
 			/* could use a vstub here */
 			restorer = NULL;
@@ -518,10 +518,10 @@ static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
 
 	/* Set up registers for signal handler */
 	regs->sp = (unsigned long) frame;
-	regs->ip = (unsigned long) ka->sa.sa_handler;
+	regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
 
 	/* We use the x32 calling convention here... */
-	regs->di = sig;
+	regs->di = ksig->sig;
 	regs->si = (unsigned long) &frame->info;
 	regs->dx = (unsigned long) &frame->uc;
 
@@ -535,70 +535,13 @@ static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
 	return 0;
 }
 
-#ifdef CONFIG_X86_32
-/*
- * Atomically swap in the new signal mask, and wait for a signal.
- */
-asmlinkage int
-sys_sigsuspend(int history0, int history1, old_sigset_t mask)
-{
-	sigset_t blocked;
-	siginitset(&blocked, mask);
-	return sigsuspend(&blocked);
-}
-
-asmlinkage int
-sys_sigaction(int sig, const struct old_sigaction __user *act,
-	      struct old_sigaction __user *oact)
-{
-	struct k_sigaction new_ka, old_ka;
-	int ret = 0;
-
-	if (act) {
-		old_sigset_t mask;
-
-		if (!access_ok(VERIFY_READ, act, sizeof(*act)))
-			return -EFAULT;
-
-		get_user_try {
-			get_user_ex(new_ka.sa.sa_handler, &act->sa_handler);
-			get_user_ex(new_ka.sa.sa_flags, &act->sa_flags);
-			get_user_ex(mask, &act->sa_mask);
-			get_user_ex(new_ka.sa.sa_restorer, &act->sa_restorer);
-		} get_user_catch(ret);
-
-		if (ret)
-			return -EFAULT;
-		siginitset(&new_ka.sa.sa_mask, mask);
-	}
-
-	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
-
-	if (!ret && oact) {
-		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
-			return -EFAULT;
-
-		put_user_try {
-			put_user_ex(old_ka.sa.sa_handler, &oact->sa_handler);
-			put_user_ex(old_ka.sa.sa_flags, &oact->sa_flags);
-			put_user_ex(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
-			put_user_ex(old_ka.sa.sa_restorer, &oact->sa_restorer);
-		} put_user_catch(ret);
-
-		if (ret)
-			return -EFAULT;
-	}
-
-	return ret;
-}
-#endif /* CONFIG_X86_32 */
-
 /*
  * Do a signal return; undo the signal stack.
  */
 #ifdef CONFIG_X86_32
-unsigned long sys_sigreturn(struct pt_regs *regs)
+unsigned long sys_sigreturn(void)
 {
+	struct pt_regs *regs = current_pt_regs();
 	struct sigframe __user *frame;
 	unsigned long ax;
 	sigset_t set;
@@ -625,8 +568,9 @@ badframe:
 }
 #endif /* CONFIG_X86_32 */
 
-long sys_rt_sigreturn(struct pt_regs *regs)
+long sys_rt_sigreturn(void)
 {
+	struct pt_regs *regs = current_pt_regs();
 	struct rt_sigframe __user *frame;
 	unsigned long ax;
 	sigset_t set;
@@ -667,30 +611,29 @@ static int signr_convert(int sig)
 }
 
 static int
-setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
-		struct pt_regs *regs)
+setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
 {
-	int usig = signr_convert(sig);
+	int usig = signr_convert(ksig->sig);
 	sigset_t *set = sigmask_to_save();
 	compat_sigset_t *cset = (compat_sigset_t *) set;
 
 	/* Set up the stack frame */
 	if (is_ia32_frame()) {
-		if (ka->sa.sa_flags & SA_SIGINFO)
-			return ia32_setup_rt_frame(usig, ka, info, cset, regs);
+		if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+			return ia32_setup_rt_frame(usig, ksig, cset, regs);
 		else
-			return ia32_setup_frame(usig, ka, cset, regs);
+			return ia32_setup_frame(usig, ksig, cset, regs);
 	} else if (is_x32_frame()) {
-		return x32_setup_rt_frame(usig, ka, info, cset, regs);
+		return x32_setup_rt_frame(ksig, cset, regs);
 	} else {
-		return __setup_rt_frame(sig, ka, info, set, regs);
+		return __setup_rt_frame(ksig->sig, ksig, set, regs);
 	}
 }
 
 static void
-handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
-		struct pt_regs *regs)
+handle_signal(struct ksignal *ksig, struct pt_regs *regs)
 {
+	bool failed;
 	/* Are we from a system call? */
 	if (syscall_get_nr(current, regs) >= 0) {
 		/* If so, check system call restarting.. */
@@ -701,7 +644,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 			break;
 
 		case -ERESTARTSYS:
-			if (!(ka->sa.sa_flags & SA_RESTART)) {
+			if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
 				regs->ax = -EINTR;
 				break;
 			}
@@ -721,26 +664,21 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	    likely(test_and_clear_thread_flag(TIF_FORCED_TF)))
 		regs->flags &= ~X86_EFLAGS_TF;
 
-	if (setup_rt_frame(sig, ka, info, regs) < 0) {
-		force_sigsegv(sig, current);
-		return;
+	failed = (setup_rt_frame(ksig, regs) < 0);
+	if (!failed) {
+		/*
+		 * Clear the direction flag as per the ABI for function entry.
+		 */
+		regs->flags &= ~X86_EFLAGS_DF;
+		/*
+		 * Clear TF when entering the signal handler, but
+		 * notify any tracer that was single-stepping it.
+		 * The tracer may want to single-step inside the
+		 * handler too.
+		 */
+		regs->flags &= ~X86_EFLAGS_TF;
 	}
-
-	/*
-	 * Clear the direction flag as per the ABI for function entry.
-	 */
-	regs->flags &= ~X86_EFLAGS_DF;
-
-	/*
-	 * Clear TF when entering the signal handler, but
-	 * notify any tracer that was single-stepping it.
-	 * The tracer may want to single-step inside the
-	 * handler too.
-	 */
-	regs->flags &= ~X86_EFLAGS_TF;
-
-	signal_delivered(sig, info, ka, regs,
-			 test_thread_flag(TIF_SINGLESTEP));
+	signal_setup_done(failed, ksig, test_thread_flag(TIF_SINGLESTEP));
 }
 
 #ifdef CONFIG_X86_32
@@ -757,14 +695,11 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
  */
 static void do_signal(struct pt_regs *regs)
 {
-	struct k_sigaction ka;
-	siginfo_t info;
-	int signr;
+	struct ksignal ksig;
 
-	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
-	if (signr > 0) {
+	if (get_signal(&ksig)) {
 		/* Whee! Actually deliver the signal.  */
-		handle_signal(signr, &info, &ka, regs);
+		handle_signal(&ksig, regs);
 		return;
 	}
 
@@ -843,8 +778,9 @@ void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
 }
 
 #ifdef CONFIG_X86_X32_ABI
-asmlinkage long sys32_x32_rt_sigreturn(struct pt_regs *regs)
+asmlinkage long sys32_x32_rt_sigreturn(void)
 {
+	struct pt_regs *regs = current_pt_regs();
 	struct rt_sigframe_x32 __user *frame;
 	sigset_t set;
 	unsigned long ax;