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() ...
2013-02-23 18:50:11 -08:00
parent 5ce1a70e2f 235b80226b
commit 9e2d59ad58
185 changed files with 1361 additions and 4823 deletions
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2399,6 +2399,15 @@ void signal_delivered(int sig, siginfo_t *info, struct k_sigaction *ka,
 	tracehook_signal_handler(sig, info, ka, regs, stepping);
 }

+void signal_setup_done(int failed, struct ksignal *ksig, int stepping)
+{
+	if (failed)
+		force_sigsegv(ksig->sig, current);
+	else
+		signal_delivered(ksig->sig, &ksig->info, &ksig->ka,
+			signal_pt_regs(), stepping);
+}
+
 /*
 * It could be that complete_signal() picked us to notify about the
 * group-wide signal. Other threads should be notified now to take
@@ -2616,28 +2625,58 @@ SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, nset,
 	return 0;
 }

-long do_sigpending(void __user *set, unsigned long sigsetsize)
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset,
+		compat_sigset_t __user *, oset, compat_size_t, sigsetsize)
 {
-	long error = -EINVAL;
-	sigset_t pending;
+#ifdef __BIG_ENDIAN
+	sigset_t old_set = current->blocked;

+	/* XXX: Don't preclude handling different sized sigset_t's.  */
+	if (sigsetsize != sizeof(sigset_t))
+		return -EINVAL;
+
+	if (nset) {
+		compat_sigset_t new32;
+		sigset_t new_set;
+		int error;
+		if (copy_from_user(&new32, nset, sizeof(compat_sigset_t)))
+			return -EFAULT;
+
+		sigset_from_compat(&new_set, &new32);
+		sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+		error = sigprocmask(how, &new_set, NULL);
+		if (error)
+			return error;
+	}
+	if (oset) {
+		compat_sigset_t old32;
+		sigset_to_compat(&old32, &old_set);
+		if (copy_to_user(oset, &old_set, sizeof(sigset_t)))
+			return -EFAULT;
+	}
+	return 0;
+#else
+	return sys_rt_sigprocmask(how, (sigset_t __user *)nset,
+				  (sigset_t __user *)oset, sigsetsize);
+#endif
+}
+#endif
+
+static int do_sigpending(void *set, unsigned long sigsetsize)
+{
 	if (sigsetsize > sizeof(sigset_t))
-		goto out;
+		return -EINVAL;

 	spin_lock_irq(&current->sighand->siglock);
-	sigorsets(&pending, &current->pending.signal,
+	sigorsets(set, &current->pending.signal,
 		  &current->signal->shared_pending.signal);
 	spin_unlock_irq(&current->sighand->siglock);

 	/* Outside the lock because only this thread touches it.  */
-	sigandsets(&pending, &current->blocked, &pending);
-
-	error = -EFAULT;
-	if (!copy_to_user(set, &pending, sigsetsize))
-		error = 0;
-
-out:
-	return error;
+	sigandsets(set, &current->blocked, set);
+	return 0;
 }

 /**
@@ -2646,11 +2685,36 @@ out:
 *  @set: stores pending signals
 *  @sigsetsize: size of sigset_t type or larger
 */
-SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, set, size_t, sigsetsize)
+SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize)
 {
-	return do_sigpending(set, sigsetsize);
+	sigset_t set;
+	int err = do_sigpending(&set, sigsetsize);
+	if (!err && copy_to_user(uset, &set, sigsetsize))
+		err = -EFAULT;
+	return err;
 }

+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset,
+		compat_size_t, sigsetsize)
+{
+#ifdef __BIG_ENDIAN
+	sigset_t set;
+	int err = do_sigpending(&set, sigsetsize);
+	if (!err) {
+		compat_sigset_t set32;
+		sigset_to_compat(&set32, &set);
+		/* we can get here only if sigsetsize <= sizeof(set) */
+		if (copy_to_user(uset, &set32, sigsetsize))
+			err = -EFAULT;
+	}
+	return err;
+#else
+	return sys_rt_sigpending((sigset_t __user *)uset, sigsetsize);
+#endif
+}
+#endif
+
 #ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER

 int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from)
@@ -2927,6 +2991,22 @@ SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig)
 	return do_tkill(0, pid, sig);
 }

+static int do_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t *info)
+{
+	/* Not even root can pretend to send signals from the kernel.
+	 * Nor can they impersonate a kill()/tgkill(), which adds source info.
+	 */
+	if (info->si_code >= 0 || info->si_code == SI_TKILL) {
+		/* We used to allow any < 0 si_code */
+		WARN_ON_ONCE(info->si_code < 0);
+		return -EPERM;
+	}
+	info->si_signo = sig;
+
+	/* POSIX.1b doesn't mention process groups.  */
+	return kill_proc_info(sig, info, pid);
+}
+
 /**
 *  sys_rt_sigqueueinfo - send signal information to a signal
 *  @pid: the PID of the thread
@@ -2937,25 +3017,26 @@ SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig,
 		siginfo_t __user *, uinfo)
 {
 	siginfo_t info;
-
 	if (copy_from_user(&info, uinfo, sizeof(siginfo_t)))
 		return -EFAULT;
-
-	/* Not even root can pretend to send signals from the kernel.
-	 * Nor can they impersonate a kill()/tgkill(), which adds source info.
-	 */
-	if (info.si_code >= 0 || info.si_code == SI_TKILL) {
-		/* We used to allow any < 0 si_code */
-		WARN_ON_ONCE(info.si_code < 0);
-		return -EPERM;
-	}
-	info.si_signo = sig;
-
-	/* POSIX.1b doesn't mention process groups.  */
-	return kill_proc_info(sig, &info, pid);
+	return do_rt_sigqueueinfo(pid, sig, &info);
 }

-long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info)
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo,
+			compat_pid_t, pid,
+			int, sig,
+			struct compat_siginfo __user *, uinfo)
+{
+	siginfo_t info;
+	int ret = copy_siginfo_from_user32(&info, uinfo);
+	if (unlikely(ret))
+		return ret;
+	return do_rt_sigqueueinfo(pid, sig, &info);
+}
+#endif
+
+static int do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info)
 {
 	/* This is only valid for single tasks */
 	if (pid <= 0 || tgid <= 0)
@@ -2985,6 +3066,21 @@ SYSCALL_DEFINE4(rt_tgsigqueueinfo, pid_t, tgid, pid_t, pid, int, sig,
 	return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
 }

+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo,
+			compat_pid_t, tgid,
+			compat_pid_t, pid,
+			int, sig,
+			struct compat_siginfo __user *, uinfo)
+{
+	siginfo_t info;
+
+	if (copy_siginfo_from_user32(&info, uinfo))
+		return -EFAULT;
+	return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
+}
+#endif
+
 int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact)
 {
 	struct task_struct *t = current;
@@ -3030,7 +3126,7 @@ int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact)
 	return 0;
 }

-int 
+static int 
 do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long sp)
 {
 	stack_t oss;
@@ -3095,12 +3191,10 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
 out:
 	return error;
 }
-#ifdef CONFIG_GENERIC_SIGALTSTACK
 SYSCALL_DEFINE2(sigaltstack,const stack_t __user *,uss, stack_t __user *,uoss)
 {
 	return do_sigaltstack(uss, uoss, current_user_stack_pointer());
 }
-#endif

 int restore_altstack(const stack_t __user *uss)
 {
@@ -3118,7 +3212,6 @@ int __save_altstack(stack_t __user *uss, unsigned long sp)
 }

 #ifdef CONFIG_COMPAT
-#ifdef CONFIG_GENERIC_SIGALTSTACK
 COMPAT_SYSCALL_DEFINE2(sigaltstack,
 			const compat_stack_t __user *, uss_ptr,
 			compat_stack_t __user *, uoss_ptr)
@@ -3168,7 +3261,6 @@ int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
 		__put_user(t->sas_ss_size, &uss->ss_size);
 }
 #endif
-#endif

 #ifdef __ARCH_WANT_SYS_SIGPENDING

@@ -3178,7 +3270,7 @@ int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
 */
 SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set)
 {
-	return do_sigpending(set, sizeof(*set));
+	return sys_rt_sigpending((sigset_t __user *)set, sizeof(old_sigset_t)); 
 }

 #endif
@@ -3234,7 +3326,7 @@ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset,
 }
 #endif /* __ARCH_WANT_SYS_SIGPROCMASK */

-#ifdef __ARCH_WANT_SYS_RT_SIGACTION
+#ifndef CONFIG_ODD_RT_SIGACTION
 /**
 *  sys_rt_sigaction - alter an action taken by a process
 *  @sig: signal to be sent
@@ -3268,7 +3360,132 @@ SYSCALL_DEFINE4(rt_sigaction, int, sig,
 out:
 	return ret;
 }
-#endif /* __ARCH_WANT_SYS_RT_SIGACTION */
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig,
+		const struct compat_sigaction __user *, act,
+		struct compat_sigaction __user *, oact,
+		compat_size_t, sigsetsize)
+{
+	struct k_sigaction new_ka, old_ka;
+	compat_sigset_t mask;
+#ifdef __ARCH_HAS_SA_RESTORER
+	compat_uptr_t restorer;
+#endif
+	int ret;
+
+	/* XXX: Don't preclude handling different sized sigset_t's.  */
+	if (sigsetsize != sizeof(compat_sigset_t))
+		return -EINVAL;
+
+	if (act) {
+		compat_uptr_t handler;
+		ret = get_user(handler, &act->sa_handler);
+		new_ka.sa.sa_handler = compat_ptr(handler);
+#ifdef __ARCH_HAS_SA_RESTORER
+		ret |= get_user(restorer, &act->sa_restorer);
+		new_ka.sa.sa_restorer = compat_ptr(restorer);
+#endif
+		ret |= copy_from_user(&mask, &act->sa_mask, sizeof(mask));
+		ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
+		if (ret)
+			return -EFAULT;
+		sigset_from_compat(&new_ka.sa.sa_mask, &mask);
+	}
+
+	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+	if (!ret && oact) {
+		sigset_to_compat(&mask, &old_ka.sa.sa_mask);
+		ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), 
+			       &oact->sa_handler);
+		ret |= copy_to_user(&oact->sa_mask, &mask, sizeof(mask));
+		ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
+#ifdef __ARCH_HAS_SA_RESTORER
+		ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer),
+				&oact->sa_restorer);
+#endif
+	}
+	return ret;
+}
+#endif
+#endif /* !CONFIG_ODD_RT_SIGACTION */
+
+#ifdef CONFIG_OLD_SIGACTION
+SYSCALL_DEFINE3(sigaction, int, sig,
+		const struct old_sigaction __user *, act,
+	        struct old_sigaction __user *, oact)
+{
+	struct k_sigaction new_ka, old_ka;
+	int ret;
+
+	if (act) {
+		old_sigset_t mask;
+		if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+		    __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
+		    __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
+		    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
+		    __get_user(mask, &act->sa_mask))
+			return -EFAULT;
+#ifdef __ARCH_HAS_KA_RESTORER
+		new_ka.ka_restorer = NULL;
+#endif
+		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)) ||
+		    __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
+		    __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
+		    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+		    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
+			return -EFAULT;
+	}
+
+	return ret;
+}
+#endif
+#ifdef CONFIG_COMPAT_OLD_SIGACTION
+COMPAT_SYSCALL_DEFINE3(sigaction, int, sig,
+		const struct compat_old_sigaction __user *, act,
+	        struct compat_old_sigaction __user *, oact)
+{
+	struct k_sigaction new_ka, old_ka;
+	int ret;
+	compat_old_sigset_t mask;
+	compat_uptr_t handler, restorer;
+
+	if (act) {
+		if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+		    __get_user(handler, &act->sa_handler) ||
+		    __get_user(restorer, &act->sa_restorer) ||
+		    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
+		    __get_user(mask, &act->sa_mask))
+			return -EFAULT;
+
+#ifdef __ARCH_HAS_KA_RESTORER
+		new_ka.ka_restorer = NULL;
+#endif
+		new_ka.sa.sa_handler = compat_ptr(handler);
+		new_ka.sa.sa_restorer = compat_ptr(restorer);
+		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)) ||
+		    __put_user(ptr_to_compat(old_ka.sa.sa_handler),
+			       &oact->sa_handler) ||
+		    __put_user(ptr_to_compat(old_ka.sa.sa_restorer),
+			       &oact->sa_restorer) ||
+		    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+		    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
+			return -EFAULT;
+	}
+	return ret;
+}
+#endif

 #ifdef __ARCH_WANT_SYS_SGETMASK

@@ -3336,7 +3553,6 @@ int sigsuspend(sigset_t *set)
 	return -ERESTARTNOHAND;
 }

-#ifdef __ARCH_WANT_SYS_RT_SIGSUSPEND
 /**
 *  sys_rt_sigsuspend - replace the signal mask for a value with the
 *	@unewset value until a signal is received
@@ -3355,7 +3571,45 @@ SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize)
 		return -EFAULT;
 	return sigsuspend(&newset);
 }
-#endif /* __ARCH_WANT_SYS_RT_SIGSUSPEND */
+ 
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_size_t, sigsetsize)
+{
+#ifdef __BIG_ENDIAN
+	sigset_t newset;
+	compat_sigset_t newset32;
+
+	/* XXX: Don't preclude handling different sized sigset_t's.  */
+	if (sigsetsize != sizeof(sigset_t))
+		return -EINVAL;
+
+	if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
+		return -EFAULT;
+	sigset_from_compat(&newset, &newset32);
+	return sigsuspend(&newset);
+#else
+	/* on little-endian bitmaps don't care about granularity */
+	return sys_rt_sigsuspend((sigset_t __user *)unewset, sigsetsize);
+#endif
+}
+#endif
+
+#ifdef CONFIG_OLD_SIGSUSPEND
+SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask)
+{
+	sigset_t blocked;
+	siginitset(&blocked, mask);
+	return sigsuspend(&blocked);
+}
+#endif
+#ifdef CONFIG_OLD_SIGSUSPEND3
+SYSCALL_DEFINE3(sigsuspend, int, unused1, int, unused2, old_sigset_t, mask)
+{
+	sigset_t blocked;
+	siginitset(&blocked, mask);
+	return sigsuspend(&blocked);
+}
+#endif

 __attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma)
 {