Merge tag 'v4.9.127' into imx_4.9.x_2.3.0_ga

This is the 4.9.127 stable release

Conflicts:
	drivers/gpu/drm/imx/imx-ldb.c
	drivers/staging/android/ion/ion_priv.h

12 files changed, 108 insertions, 93 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 2c98b987808d..5d0e2f366766 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1304,7 +1304,9 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
 		return -ENOMEM;
 
 	atomic_set(&sig->count, 1);
+	spin_lock_irq(&current->sighand->siglock);
 	memcpy(sig->action, current->sighand->action, sizeof(sig->action));
+	spin_unlock_irq(&current->sighand->siglock);
 	return 0;
 }
 
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 69485183af79..b9e966bcdd20 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2441,7 +2441,7 @@ static int __init debugfs_kprobe_init(void)
 	if (!dir)
 		return -ENOMEM;
 
-	file = debugfs_create_file("list", 0444, dir, NULL,
+	file = debugfs_create_file("list", 0400, dir, NULL,
 				&debugfs_kprobes_operations);
 	if (!file)
 		goto error;
@@ -2451,7 +2451,7 @@ static int __init debugfs_kprobe_init(void)
 	if (!file)
 		goto error;
 
-	file = debugfs_create_file("blacklist", 0444, dir, NULL,
+	file = debugfs_create_file("blacklist", 0400, dir, NULL,
 				&debugfs_kprobe_blacklist_ops);
 	if (!file)
 		goto error;
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 6599c7f3071d..61a15e538435 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1240,11 +1240,11 @@ unsigned long lockdep_count_forward_deps(struct lock_class *class)
 	this.parent = NULL;
 	this.class = class;
 
-	local_irq_save(flags);
+	raw_local_irq_save(flags);
 	arch_spin_lock(&lockdep_lock);
 	ret = __lockdep_count_forward_deps(&this);
 	arch_spin_unlock(&lockdep_lock);
-	local_irq_restore(flags);
+	raw_local_irq_restore(flags);
 
 	return ret;
 }
@@ -1267,11 +1267,11 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class)
 	this.parent = NULL;
 	this.class = class;
 
-	local_irq_save(flags);
+	raw_local_irq_save(flags);
 	arch_spin_lock(&lockdep_lock);
 	ret = __lockdep_count_backward_deps(&this);
 	arch_spin_unlock(&lockdep_lock);
-	local_irq_restore(flags);
+	raw_local_irq_restore(flags);
 
 	return ret;
 }
@@ -4273,7 +4273,7 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
 	if (unlikely(!debug_locks))
 		return;
 
-	local_irq_save(flags);
+	raw_local_irq_save(flags);
 	for (i = 0; i < curr->lockdep_depth; i++) {
 		hlock = curr->held_locks + i;
 
@@ -4284,7 +4284,7 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
 		print_freed_lock_bug(curr, mem_from, mem_from + mem_len, hlock);
 		break;
 	}
-	local_irq_restore(flags);
+	raw_local_irq_restore(flags);
 }
 EXPORT_SYMBOL_GPL(debug_check_no_locks_freed);
 
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index e8517b63eb37..dd2b5a4d89a5 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -105,6 +105,7 @@ config PM_SLEEP
 	def_bool y
 	depends on SUSPEND || HIBERNATE_CALLBACKS
 	select PM
+	select SRCU
 
 config PM_SLEEP_SMP
 	def_bool y
diff --git a/kernel/printk/nmi.c b/kernel/printk/nmi.c
index 5fa65aa904d3..2c3e7f024c15 100644
--- a/kernel/printk/nmi.c
+++ b/kernel/printk/nmi.c
@@ -260,12 +260,12 @@ void __init printk_nmi_init(void)
 	printk_nmi_flush();
 }
 
-void printk_nmi_enter(void)
+void notrace printk_nmi_enter(void)
 {
 	this_cpu_write(printk_func, vprintk_nmi);
 }
 
-void printk_nmi_exit(void)
+void notrace printk_nmi_exit(void)
 {
 	this_cpu_write(printk_func, vprintk_default);
 }
diff --git a/kernel/sys.c b/kernel/sys.c
index b13b530b5e0f..6c4e9b533258 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1142,18 +1142,19 @@ static int override_release(char __user *release, size_t len)
 
 SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
 {
-	int errno = 0;
+	struct new_utsname tmp;
 
 	down_read(&uts_sem);
-	if (copy_to_user(name, utsname(), sizeof *name))
-		errno = -EFAULT;
+	memcpy(&tmp, utsname(), sizeof(tmp));
 	up_read(&uts_sem);
+	if (copy_to_user(name, &tmp, sizeof(tmp)))
+		return -EFAULT;
 
-	if (!errno && override_release(name->release, sizeof(name->release)))
-		errno = -EFAULT;
-	if (!errno && override_architecture(name))
-		errno = -EFAULT;
-	return errno;
+	if (override_release(name->release, sizeof(name->release)))
+		return -EFAULT;
+	if (override_architecture(name))
+		return -EFAULT;
+	return 0;
 }
 
 #ifdef __ARCH_WANT_SYS_OLD_UNAME
@@ -1162,55 +1163,46 @@ SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
  */
 SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
 {
-	int error = 0;
+	struct old_utsname tmp;
 
 	if (!name)
 		return -EFAULT;
 
 	down_read(&uts_sem);
-	if (copy_to_user(name, utsname(), sizeof(*name)))
-		error = -EFAULT;
+	memcpy(&tmp, utsname(), sizeof(tmp));
 	up_read(&uts_sem);
+	if (copy_to_user(name, &tmp, sizeof(tmp)))
+		return -EFAULT;
 
-	if (!error && override_release(name->release, sizeof(name->release)))
-		error = -EFAULT;
-	if (!error && override_architecture(name))
-		error = -EFAULT;
-	return error;
+	if (override_release(name->release, sizeof(name->release)))
+		return -EFAULT;
+	if (override_architecture(name))
+		return -EFAULT;
+	return 0;
 }
 
 SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
 {
-	int error;
+	struct oldold_utsname tmp = {};
 
 	if (!name)
 		return -EFAULT;
-	if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
-		return -EFAULT;
 
 	down_read(&uts_sem);
-	error = __copy_to_user(&name->sysname, &utsname()->sysname,
-			       __OLD_UTS_LEN);
-	error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
-	error |= __copy_to_user(&name->nodename, &utsname()->nodename,
-				__OLD_UTS_LEN);
-	error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
-	error |= __copy_to_user(&name->release, &utsname()->release,
-				__OLD_UTS_LEN);
-	error |= __put_user(0, name->release + __OLD_UTS_LEN);
-	error |= __copy_to_user(&name->version, &utsname()->version,
-				__OLD_UTS_LEN);
-	error |= __put_user(0, name->version + __OLD_UTS_LEN);
-	error |= __copy_to_user(&name->machine, &utsname()->machine,
-				__OLD_UTS_LEN);
-	error |= __put_user(0, name->machine + __OLD_UTS_LEN);
+	memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
+	memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);
+	memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN);
+	memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN);
+	memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN);
 	up_read(&uts_sem);
+	if (copy_to_user(name, &tmp, sizeof(tmp)))
+		return -EFAULT;
 
-	if (!error && override_architecture(name))
-		error = -EFAULT;
-	if (!error && override_release(name->release, sizeof(name->release)))
-		error = -EFAULT;
-	return error ? -EFAULT : 0;
+	if (override_architecture(name))
+		return -EFAULT;
+	if (override_release(name->release, sizeof(name->release)))
+		return -EFAULT;
+	return 0;
 }
 #endif
 
@@ -1224,17 +1216,18 @@ SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
 
 	if (len < 0 || len > __NEW_UTS_LEN)
 		return -EINVAL;
-	down_write(&uts_sem);
 	errno = -EFAULT;
 	if (!copy_from_user(tmp, name, len)) {
-		struct new_utsname *u = utsname();
+		struct new_utsname *u;
 
+		down_write(&uts_sem);
+		u = utsname();
 		memcpy(u->nodename, tmp, len);
 		memset(u->nodename + len, 0, sizeof(u->nodename) - len);
 		errno = 0;
 		uts_proc_notify(UTS_PROC_HOSTNAME);
+		up_write(&uts_sem);
 	}
-	up_write(&uts_sem);
 	return errno;
 }
 
@@ -1242,8 +1235,9 @@ SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
 
 SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
 {
-	int i, errno;
+	int i;
 	struct new_utsname *u;
+	char tmp[__NEW_UTS_LEN + 1];
 
 	if (len < 0)
 		return -EINVAL;
@@ -1252,11 +1246,11 @@ SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
 	i = 1 + strlen(u->nodename);
 	if (i > len)
 		i = len;
-	errno = 0;
-	if (copy_to_user(name, u->nodename, i))
-		errno = -EFAULT;
+	memcpy(tmp, u->nodename, i);
 	up_read(&uts_sem);
-	return errno;
+	if (copy_to_user(name, tmp, i))
+		return -EFAULT;
+	return 0;
 }
 
 #endif
@@ -1275,17 +1269,18 @@ SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
 	if (len < 0 || len > __NEW_UTS_LEN)
 		return -EINVAL;
 
-	down_write(&uts_sem);
 	errno = -EFAULT;
 	if (!copy_from_user(tmp, name, len)) {
-		struct new_utsname *u = utsname();
+		struct new_utsname *u;
 
+		down_write(&uts_sem);
+		u = utsname();
 		memcpy(u->domainname, tmp, len);
 		memset(u->domainname + len, 0, sizeof(u->domainname) - len);
 		errno = 0;
 		uts_proc_notify(UTS_PROC_DOMAINNAME);
+		up_write(&uts_sem);
 	}
-	up_write(&uts_sem);
 	return errno;
 }
 
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 24d603d29512..7df6be31be36 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -345,7 +345,8 @@ static struct ctl_table kern_table[] = {
 		.data		= &sysctl_sched_time_avg,
 		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one,
 	},
 	{
 		.procname	= "sched_shares_window_ns",
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 77bf690cbacb..55257a3763f9 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -1720,6 +1720,10 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
 	mutex_lock(&bdev->bd_mutex);
 
 	if (attr == &dev_attr_enable) {
+		if (!!value == !!q->blk_trace) {
+			ret = 0;
+			goto out_unlock_bdev;
+		}
 		if (value)
 			ret = blk_trace_setup_queue(q, bdev);
 		else
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 901c7f15f6e2..a47339b156ce 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2525,6 +2525,7 @@ out_nobuffer:
 }
 EXPORT_SYMBOL_GPL(trace_vbprintk);
 
+__printf(3, 0)
 static int
 __trace_array_vprintk(struct ring_buffer *buffer,
 		      unsigned long ip, const char *fmt, va_list args)
@@ -2579,12 +2580,14 @@ out_nobuffer:
 	return len;
 }
 
+__printf(3, 0)
 int trace_array_vprintk(struct trace_array *tr,
 			unsigned long ip, const char *fmt, va_list args)
 {
 	return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args);
 }
 
+__printf(3, 0)
 int trace_array_printk(struct trace_array *tr,
 		       unsigned long ip, const char *fmt, ...)
 {
@@ -2600,6 +2603,7 @@ int trace_array_printk(struct trace_array *tr,
 	return ret;
 }
 
+__printf(3, 4)
 int trace_array_printk_buf(struct ring_buffer *buffer,
 			   unsigned long ip, const char *fmt, ...)
 {
@@ -2615,6 +2619,7 @@ int trace_array_printk_buf(struct ring_buffer *buffer,
 	return ret;
 }
 
+__printf(2, 0)
 int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
 {
 	return trace_array_vprintk(&global_trace, ip, fmt, args);
@@ -6915,7 +6920,9 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
 
 	if (buffer) {
 		mutex_lock(&trace_types_lock);
-		if (val) {
+		if (!!val == tracer_tracing_is_on(tr)) {
+			val = 0; /* do nothing */
+		} else if (val) {
 			tracer_tracing_on(tr);
 			if (tr->current_trace->start)
 				tr->current_trace->start(tr);
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 788262984818..f0ab801a6437 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -969,7 +969,7 @@ probe_event_disable(struct trace_uprobe *tu, struct trace_event_file *file)
 
 		list_del_rcu(&link->list);
 		/* synchronize with u{,ret}probe_trace_func */
-		synchronize_sched();
+		synchronize_rcu();
 		kfree(link);
 
 		if (!list_empty(&tu->tp.files))
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 86b7854fec8e..f789bbba9b8e 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -649,7 +649,16 @@ static ssize_t map_write(struct file *file, const char __user *buf,
 	unsigned idx;
 	struct uid_gid_extent *extent = NULL;
 	char *kbuf = NULL, *pos, *next_line;
-	ssize_t ret = -EINVAL;
+	ssize_t ret;
+
+	/* Only allow < page size writes at the beginning of the file */
+	if ((*ppos != 0) || (count >= PAGE_SIZE))
+		return -EINVAL;
+
+	/* Slurp in the user data */
+	kbuf = memdup_user_nul(buf, count);
+	if (IS_ERR(kbuf))
+		return PTR_ERR(kbuf);
 
 	/*
 	 * The userns_state_mutex serializes all writes to any given map.
@@ -683,19 +692,6 @@ static ssize_t map_write(struct file *file, const char __user *buf,
 	if (cap_valid(cap_setid) && !file_ns_capable(file, ns, CAP_SYS_ADMIN))
 		goto out;
 
-	/* Only allow < page size writes at the beginning of the file */
-	ret = -EINVAL;
-	if ((*ppos != 0) || (count >= PAGE_SIZE))
-		goto out;
-
-	/* Slurp in the user data */
-	kbuf = memdup_user_nul(buf, count);
-	if (IS_ERR(kbuf)) {
-		ret = PTR_ERR(kbuf);
-		kbuf = NULL;
-		goto out;
-	}
-
 	/* Parse the user data */
 	ret = -EINVAL;
 	pos = kbuf;
diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c
index c8eac43267e9..d2b3b2973456 100644
--- a/kernel/utsname_sysctl.c
+++ b/kernel/utsname_sysctl.c
@@ -17,7 +17,7 @@
 
 #ifdef CONFIG_PROC_SYSCTL
 
-static void *get_uts(struct ctl_table *table, int write)
+static void *get_uts(struct ctl_table *table)
 {
 	char *which = table->data;
 	struct uts_namespace *uts_ns;
@@ -25,21 +25,9 @@ static void *get_uts(struct ctl_table *table, int write)
 	uts_ns = current->nsproxy->uts_ns;
 	which = (which - (char *)&init_uts_ns) + (char *)uts_ns;
 
-	if (!write)
-		down_read(&uts_sem);
-	else
-		down_write(&uts_sem);
 	return which;
 }
 
-static void put_uts(struct ctl_table *table, int write, void *which)
-{
-	if (!write)
-		up_read(&uts_sem);
-	else
-		up_write(&uts_sem);
-}
-
 /*
  *	Special case of dostring for the UTS structure. This has locks
  *	to observe. Should this be in kernel/sys.c ????
@@ -49,13 +37,34 @@ static int proc_do_uts_string(struct ctl_table *table, int write,
 {
 	struct ctl_table uts_table;
 	int r;
+	char tmp_data[__NEW_UTS_LEN + 1];
+
 	memcpy(&uts_table, table, sizeof(uts_table));
-	uts_table.data = get_uts(table, write);
+	uts_table.data = tmp_data;
+
+	/*
+	 * Buffer the value in tmp_data so that proc_dostring() can be called
+	 * without holding any locks.
+	 * We also need to read the original value in the write==1 case to
+	 * support partial writes.
+	 */
+	down_read(&uts_sem);
+	memcpy(tmp_data, get_uts(table), sizeof(tmp_data));
+	up_read(&uts_sem);
 	r = proc_dostring(&uts_table, write, buffer, lenp, ppos);
-	put_uts(table, write, uts_table.data);
 
-	if (write)
+	if (write) {
+		/*
+		 * Write back the new value.
+		 * Note that, since we dropped uts_sem, the result can
+		 * theoretically be incorrect if there are two parallel writes
+		 * at non-zero offsets to the same sysctl.
+		 */
+		down_write(&uts_sem);
+		memcpy(get_uts(table), tmp_data, sizeof(tmp_data));
+		up_write(&uts_sem);
 		proc_sys_poll_notify(table->poll);
+	}
 
 	return r;
 }