Merge tag 'v4.6-rc3' into perf/core, to refresh the tree

Signed-off-by: Ingo Molnar <mingo@kernel.org>

89 files changed, 3485 insertions, 1299 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 53abf008ecb3..f0c40bf49d9f 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -14,11 +14,21 @@ obj-y     = fork.o exec_domain.o panic.o \
 obj-$(CONFIG_MULTIUSER) += groups.o
 
 ifdef CONFIG_FUNCTION_TRACER
-# Do not trace debug files and internal ftrace files
-CFLAGS_REMOVE_cgroup-debug.o = $(CC_FLAGS_FTRACE)
+# Do not trace internal ftrace files
 CFLAGS_REMOVE_irq_work.o = $(CC_FLAGS_FTRACE)
 endif
 
+# Prevents flicker of uninteresting __do_softirq()/__local_bh_disable_ip()
+# in coverage traces.
+KCOV_INSTRUMENT_softirq.o := n
+# These are called from save_stack_trace() on slub debug path,
+# and produce insane amounts of uninteresting coverage.
+KCOV_INSTRUMENT_module.o := n
+KCOV_INSTRUMENT_extable.o := n
+# Don't self-instrument.
+KCOV_INSTRUMENT_kcov.o := n
+KASAN_SANITIZE_kcov.o := n
+
 # cond_syscall is currently not LTO compatible
 CFLAGS_sys_ni.o = $(DISABLE_LTO)
 
@@ -69,6 +79,7 @@ obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
 obj-$(CONFIG_AUDIT_WATCH) += audit_watch.o audit_fsnotify.o
 obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
 obj-$(CONFIG_GCOV_KERNEL) += gcov/
+obj-$(CONFIG_KCOV) += kcov.o
 obj-$(CONFIG_KPROBES) += kprobes.o
 obj-$(CONFIG_KGDB) += debug/
 obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
diff --git a/kernel/audit.c b/kernel/audit.c
index 3a3e5deeda8d..678c3f000191 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -809,6 +809,16 @@ static int audit_set_feature(struct sk_buff *skb)
 	return 0;
 }
 
+static int audit_replace(pid_t pid)
+{
+	struct sk_buff *skb = audit_make_reply(0, 0, AUDIT_REPLACE, 0, 0,
+					       &pid, sizeof(pid));
+
+	if (!skb)
+		return -ENOMEM;
+	return netlink_unicast(audit_sock, skb, audit_nlk_portid, 0);
+}
+
 static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	u32			seq;
@@ -870,9 +880,17 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		}
 		if (s.mask & AUDIT_STATUS_PID) {
 			int new_pid = s.pid;
+			pid_t requesting_pid = task_tgid_vnr(current);
 
-			if ((!new_pid) && (task_tgid_vnr(current) != audit_pid))
+			if ((!new_pid) && (requesting_pid != audit_pid)) {
+				audit_log_config_change("audit_pid", new_pid, audit_pid, 0);
 				return -EACCES;
+			}
+			if (audit_pid && new_pid &&
+			    audit_replace(requesting_pid) != -ECONNREFUSED) {
+				audit_log_config_change("audit_pid", new_pid, audit_pid, 0);
+				return -EEXIST;
+			}
 			if (audit_enabled != AUDIT_OFF)
 				audit_log_config_change("audit_pid", new_pid, audit_pid, 1);
 			audit_pid = new_pid;
@@ -920,7 +938,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		if (err == 1) { /* match or error */
 			err = 0;
 			if (msg_type == AUDIT_USER_TTY) {
-				err = tty_audit_push_current();
+				err = tty_audit_push();
 				if (err)
 					break;
 			}
@@ -1030,20 +1048,19 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		break;
 	case AUDIT_TTY_GET: {
 		struct audit_tty_status s;
-		struct task_struct *tsk = current;
+		unsigned int t;
 
-		spin_lock(&tsk->sighand->siglock);
-		s.enabled = tsk->signal->audit_tty;
-		s.log_passwd = tsk->signal->audit_tty_log_passwd;
-		spin_unlock(&tsk->sighand->siglock);
+		t = READ_ONCE(current->signal->audit_tty);
+		s.enabled = t & AUDIT_TTY_ENABLE;
+		s.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD);
 
 		audit_send_reply(skb, seq, AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
 		break;
 	}
 	case AUDIT_TTY_SET: {
 		struct audit_tty_status s, old;
-		struct task_struct *tsk = current;
 		struct audit_buffer	*ab;
+		unsigned int t;
 
 		memset(&s, 0, sizeof(s));
 		/* guard against past and future API changes */
@@ -1053,14 +1070,14 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		    (s.log_passwd != 0 && s.log_passwd != 1))
 			err = -EINVAL;
 
-		spin_lock(&tsk->sighand->siglock);
-		old.enabled = tsk->signal->audit_tty;
-		old.log_passwd = tsk->signal->audit_tty_log_passwd;
-		if (!err) {
-			tsk->signal->audit_tty = s.enabled;
-			tsk->signal->audit_tty_log_passwd = s.log_passwd;
+		if (err)
+			t = READ_ONCE(current->signal->audit_tty);
+		else {
+			t = s.enabled | (-s.log_passwd & AUDIT_TTY_LOG_PASSWD);
+			t = xchg(&current->signal->audit_tty, t);
 		}
-		spin_unlock(&tsk->sighand->siglock);
+		old.enabled = t & AUDIT_TTY_ENABLE;
+		old.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD);
 
 		audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
 		audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d"
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 9f194aad0adc..3cf1c5978d39 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -185,7 +185,7 @@ static struct audit_watch *audit_init_watch(char *path)
 	return watch;
 }
 
-/* Translate a watch string to kernel respresentation. */
+/* Translate a watch string to kernel representation. */
 int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op)
 {
 	struct audit_watch *watch;
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index b8ff9e193753..94ca7b1e5e7e 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -158,7 +158,7 @@ char *audit_unpack_string(void **bufp, size_t *remain, size_t len)
 	return str;
 }
 
-/* Translate an inode field to kernel respresentation. */
+/* Translate an inode field to kernel representation. */
 static inline int audit_to_inode(struct audit_krule *krule,
 				 struct audit_field *f)
 {
@@ -415,7 +415,7 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
 	return 0;
 }
 
-/* Translate struct audit_rule_data to kernel's rule respresentation. */
+/* Translate struct audit_rule_data to kernel's rule representation. */
 static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 					       size_t datasz)
 {
@@ -593,7 +593,7 @@ static inline size_t audit_pack_string(void **bufp, const char *str)
 	return len;
 }
 
-/* Translate kernel rule respresentation to struct audit_rule_data. */
+/* Translate kernel rule representation to struct audit_rule_data. */
 static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
 {
 	struct audit_rule_data *data;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 195ffaee50b9..7d0e3cf8abe1 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2412,8 +2412,8 @@ void __audit_seccomp(unsigned long syscall, long signr, int code)
 		return;
 	audit_log_task(ab);
 	audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
-			 signr, syscall_get_arch(), syscall, is_compat_task(),
-			 KSTK_EIP(current), code);
+			 signr, syscall_get_arch(), syscall,
+			 in_compat_syscall(), KSTK_EIP(current), code);
 	audit_log_end(ab);
 }
 
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 13272582eee0..eed911d091da 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1,4 +1,7 @@
 obj-y := core.o
 
 obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o
-obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o
+obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o
+ifeq ($(CONFIG_PERF_EVENTS),y)
+obj-$(CONFIG_BPF_SYSCALL) += stackmap.o
+endif
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 89ebbc4d1164..76d5a794e426 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -17,15 +17,43 @@
 #include <linux/filter.h>
 #include <linux/perf_event.h>
 
+static void bpf_array_free_percpu(struct bpf_array *array)
+{
+	int i;
+
+	for (i = 0; i < array->map.max_entries; i++)
+		free_percpu(array->pptrs[i]);
+}
+
+static int bpf_array_alloc_percpu(struct bpf_array *array)
+{
+	void __percpu *ptr;
+	int i;
+
+	for (i = 0; i < array->map.max_entries; i++) {
+		ptr = __alloc_percpu_gfp(array->elem_size, 8,
+					 GFP_USER | __GFP_NOWARN);
+		if (!ptr) {
+			bpf_array_free_percpu(array);
+			return -ENOMEM;
+		}
+		array->pptrs[i] = ptr;
+	}
+
+	return 0;
+}
+
 /* Called from syscall */
 static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 {
+	bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
 	struct bpf_array *array;
-	u32 elem_size, array_size;
+	u64 array_size;
+	u32 elem_size;
 
 	/* check sanity of attributes */
 	if (attr->max_entries == 0 || attr->key_size != 4 ||
-	    attr->value_size == 0)
+	    attr->value_size == 0 || attr->map_flags)
 		return ERR_PTR(-EINVAL);
 
 	if (attr->value_size >= 1 << (KMALLOC_SHIFT_MAX - 1))
@@ -36,12 +64,16 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 
 	elem_size = round_up(attr->value_size, 8);
 
-	/* check round_up into zero and u32 overflow */
-	if (elem_size == 0 ||
-	    attr->max_entries > (U32_MAX - PAGE_SIZE - sizeof(*array)) / elem_size)
+	array_size = sizeof(*array);
+	if (percpu)
+		array_size += (u64) attr->max_entries * sizeof(void *);
+	else
+		array_size += (u64) attr->max_entries * elem_size;
+
+	/* make sure there is no u32 overflow later in round_up() */
+	if (array_size >= U32_MAX - PAGE_SIZE)
 		return ERR_PTR(-ENOMEM);
 
-	array_size = sizeof(*array) + attr->max_entries * elem_size;
 
 	/* allocate all map elements and zero-initialize them */
 	array = kzalloc(array_size, GFP_USER | __GFP_NOWARN);
@@ -52,12 +84,25 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 	}
 
 	/* copy mandatory map attributes */
+	array->map.map_type = attr->map_type;
 	array->map.key_size = attr->key_size;
 	array->map.value_size = attr->value_size;
 	array->map.max_entries = attr->max_entries;
-	array->map.pages = round_up(array_size, PAGE_SIZE) >> PAGE_SHIFT;
 	array->elem_size = elem_size;
 
+	if (!percpu)
+		goto out;
+
+	array_size += (u64) attr->max_entries * elem_size * num_possible_cpus();
+
+	if (array_size >= U32_MAX - PAGE_SIZE ||
+	    elem_size > PCPU_MIN_UNIT_SIZE || bpf_array_alloc_percpu(array)) {
+		kvfree(array);
+		return ERR_PTR(-ENOMEM);
+	}
+out:
+	array->map.pages = round_up(array_size, PAGE_SIZE) >> PAGE_SHIFT;
+
 	return &array->map;
 }
 
@@ -67,12 +112,50 @@ static void *array_map_lookup_elem(struct bpf_map *map, void *key)
 	struct bpf_array *array = container_of(map, struct bpf_array, map);
 	u32 index = *(u32 *)key;
 
-	if (index >= array->map.max_entries)
+	if (unlikely(index >= array->map.max_entries))
 		return NULL;
 
 	return array->value + array->elem_size * index;
 }
 
+/* Called from eBPF program */
+static void *percpu_array_map_lookup_elem(struct bpf_map *map, void *key)
+{
+	struct bpf_array *array = container_of(map, struct bpf_array, map);
+	u32 index = *(u32 *)key;
+
+	if (unlikely(index >= array->map.max_entries))
+		return NULL;
+
+	return this_cpu_ptr(array->pptrs[index]);
+}
+
+int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value)
+{
+	struct bpf_array *array = container_of(map, struct bpf_array, map);
+	u32 index = *(u32 *)key;
+	void __percpu *pptr;
+	int cpu, off = 0;
+	u32 size;
+
+	if (unlikely(index >= array->map.max_entries))
+		return -ENOENT;
+
+	/* per_cpu areas are zero-filled and bpf programs can only
+	 * access 'value_size' of them, so copying rounded areas
+	 * will not leak any kernel data
+	 */
+	size = round_up(map->value_size, 8);
+	rcu_read_lock();
+	pptr = array->pptrs[index];
+	for_each_possible_cpu(cpu) {
+		bpf_long_memcpy(value + off, per_cpu_ptr(pptr, cpu), size);
+		off += size;
+	}
+	rcu_read_unlock();
+	return 0;
+}
+
 /* Called from syscall */
 static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
 {
@@ -99,19 +182,62 @@ static int array_map_update_elem(struct bpf_map *map, void *key, void *value,
 	struct bpf_array *array = container_of(map, struct bpf_array, map);
 	u32 index = *(u32 *)key;
 
-	if (map_flags > BPF_EXIST)
+	if (unlikely(map_flags > BPF_EXIST))
 		/* unknown flags */
 		return -EINVAL;
 
-	if (index >= array->map.max_entries)
+	if (unlikely(index >= array->map.max_entries))
 		/* all elements were pre-allocated, cannot insert a new one */
 		return -E2BIG;
 
-	if (map_flags == BPF_NOEXIST)
+	if (unlikely(map_flags == BPF_NOEXIST))
 		/* all elements already exist */
 		return -EEXIST;
 
-	memcpy(array->value + array->elem_