22 files changed, 1889 insertions, 494 deletions

diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index f2d7be596966..375b933010dd 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -2,7 +2,7 @@
 obj-y := core.o
 CFLAGS_core.o += $(call cc-disable-warning, override-init)
 
-obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o
+obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o task_iter.o
 obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o
 obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o
 obj-$(CONFIG_BPF_SYSCALL) += disasm.o
@@ -12,9 +12,6 @@ obj-$(CONFIG_BPF_JIT) += dispatcher.o
 ifeq ($(CONFIG_NET),y)
 obj-$(CONFIG_BPF_SYSCALL) += devmap.o
 obj-$(CONFIG_BPF_SYSCALL) += cpumap.o
-ifeq ($(CONFIG_XDP_SOCKETS),y)
-obj-$(CONFIG_BPF_SYSCALL) += xskmap.o
-endif
 obj-$(CONFIG_BPF_SYSCALL) += offload.o
 endif
 ifeq ($(CONFIG_PERF_EVENTS),y)
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 1d6120fd5ba6..11584618e861 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -77,7 +77,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 	bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
 	int ret, numa_node = bpf_map_attr_numa_node(attr);
 	u32 elem_size, index_mask, max_entries;
-	bool unpriv = !capable(CAP_SYS_ADMIN);
+	bool bypass_spec_v1 = bpf_bypass_spec_v1();
 	u64 cost, array_size, mask64;
 	struct bpf_map_memory mem;
 	struct bpf_array *array;
@@ -95,7 +95,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 	mask64 -= 1;
 
 	index_mask = mask64;
-	if (unpriv) {
+	if (!bypass_spec_v1) {
 		/* round up array size to nearest power of 2,
 		 * since cpu will speculate within index_mask limits
 		 */
@@ -149,7 +149,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 		return ERR_PTR(-ENOMEM);
 	}
 	array->index_mask = index_mask;
-	array->map.unpriv_array = unpriv;
+	array->map.bypass_spec_v1 = bypass_spec_v1;
 
 	/* copy mandatory map attributes */
 	bpf_map_init_from_attr(&array->map, attr);
@@ -219,7 +219,7 @@ static u32 array_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
 
 	*insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value));
 	*insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
-	if (map->unpriv_array) {
+	if (!map->bypass_spec_v1) {
 		*insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 4);
 		*insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask);
 	} else {
@@ -1058,7 +1058,7 @@ static u32 array_of_map_gen_lookup(struct bpf_map *map,
 
 	*insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value));
 	*insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
-	if (map->unpriv_array) {
+	if (!map->bypass_spec_v1) {
 		*insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 6);
 		*insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask);
 	} else {
diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
new file mode 100644
index 000000000000..dd612b80b9fe
--- /dev/null
+++ b/kernel/bpf/bpf_iter.c
@@ -0,0 +1,539 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2020 Facebook */
+
+#include <linux/fs.h>
+#include <linux/anon_inodes.h>
+#include <linux/filter.h>
+#include <linux/bpf.h>
+
+struct bpf_iter_target_info {
+	struct list_head list;
+	const struct bpf_iter_reg *reg_info;
+	u32 btf_id;	/* cached value */
+};
+
+struct bpf_iter_link {
+	struct bpf_link link;
+	struct bpf_iter_target_info *tinfo;
+};
+
+struct bpf_iter_priv_data {
+	struct bpf_iter_target_info *tinfo;
+	struct bpf_prog *prog;
+	u64 session_id;
+	u64 seq_num;
+	bool done_stop;
+	u8 target_private[] __aligned(8);
+};
+
+static struct list_head targets = LIST_HEAD_INIT(targets);
+static DEFINE_MUTEX(targets_mutex);
+
+/* protect bpf_iter_link changes */
+static DEFINE_MUTEX(link_mutex);
+
+/* incremented on every opened seq_file */
+static atomic64_t session_id;
+
+static int prepare_seq_file(struct file *file, struct bpf_iter_link *link);
+
+static void bpf_iter_inc_seq_num(struct seq_file *seq)
+{
+	struct bpf_iter_priv_data *iter_priv;
+
+	iter_priv = container_of(seq->private, struct bpf_iter_priv_data,
+				 target_private);
+	iter_priv->seq_num++;
+}
+
+static void bpf_iter_dec_seq_num(struct seq_file *seq)
+{
+	struct bpf_iter_priv_data *iter_priv;
+
+	iter_priv = container_of(seq->private, struct bpf_iter_priv_data,
+				 target_private);
+	iter_priv->seq_num--;
+}
+
+static void bpf_iter_done_stop(struct seq_file *seq)
+{
+	struct bpf_iter_priv_data *iter_priv;
+
+	iter_priv = container_of(seq->private, struct bpf_iter_priv_data,
+				 target_private);
+	iter_priv->done_stop = true;
+}
+
+/* bpf_seq_read, a customized and simpler version for bpf iterator.
+ * no_llseek is assumed for this file.
+ * The following are differences from seq_read():
+ *  . fixed buffer size (PAGE_SIZE)
+ *  . assuming no_llseek
+ *  . stop() may call bpf program, handling potential overflow there
+ */
+static ssize_t bpf_seq_read(struct file *file, char __user *buf, size_t size,
+			    loff_t *ppos)
+{
+	struct seq_file *seq = file->private_data;
+	size_t n, offs, copied = 0;
+	int err = 0;
+	void *p;
+
+	mutex_lock(&seq->lock);
+
+	if (!seq->buf) {
+		seq->size = PAGE_SIZE;
+		seq->buf = kmalloc(seq->size, GFP_KERNEL);
+		if (!seq->buf) {
+			err = -ENOMEM;
+			goto done;
+		}
+	}
+
+	if (seq->count) {
+		n = min(seq->count, size);
+		err = copy_to_user(buf, seq->buf + seq->from, n);
+		if (err) {
+			err = -EFAULT;
+			goto done;
+		}
+		seq->count -= n;
+		seq->from += n;
+		copied = n;
+		goto done;
+	}
+
+	seq->from = 0;
+	p = seq->op->start(seq, &seq->index);
+	if (!p)
+		goto stop;
+	if (IS_ERR(p)) {
+		err = PTR_ERR(p);
+		seq->op->stop(seq, p);
+		seq->count = 0;
+		goto done;
+	}
+
+	err = seq->op->show(seq, p);
+	if (err > 0) {
+		/* object is skipped, decrease seq_num, so next
+		 * valid object can reuse the same seq_num.
+		 */
+		bpf_iter_dec_seq_num(seq);
+		seq->count = 0;
+	} else if (err < 0 || seq_has_overflowed(seq)) {
+		if (!err)
+			err = -E2BIG;
+		seq->op->stop(seq, p);
+		seq->count = 0;
+		goto done;
+	}
+
+	while (1) {
+		loff_t pos = seq->index;
+
+		offs = seq->count;
+		p = seq->op->next(seq, p, &seq->index);
+		if (pos == seq->index) {
+			pr_info_ratelimited("buggy seq_file .next function %ps "
+				"did not updated position index\n",
+				seq->op->next);
+			seq->index++;
+		}
+
+		if (IS_ERR_OR_NULL(p))
+			break;
+
+		/* got a valid next object, increase seq_num */
+		bpf_iter_inc_seq_num(seq);
+
+		if (seq->count >= size)
+			break;
+
+		err = seq->op->show(seq, p);
+		if (err > 0) {
+			bpf_iter_dec_seq_num(seq);
+			seq->count = offs;
+		} else if (err < 0 || seq_has_overflowed(seq)) {
+			seq->count = offs;
+			if (offs == 0) {
+				if (!err)
+					err = -E2BIG;
+				seq->op->stop(seq, p);
+				goto done;
+			}
+			break;
+		}
+	}
+stop:
+	offs = seq->count;
+	/* bpf program called if !p */
+	seq->op->stop(seq, p);
+	if (!p) {
+		if (!seq_has_overflowed(seq)) {
+			bpf_iter_done_stop(seq);
+		} else {
+			seq->count = offs;
+			if (offs == 0) {
+				err = -E2BIG;
+				goto done;
+			}
+		}
+	}
+
+	n = min(seq->count, size);
+	err = copy_to_user(buf, seq->buf, n);
+	if (err) {
+		err = -EFAULT;
+		goto done;
+	}
+	copied = n;
+	seq->count -= n;
+	seq->from = n;
+done:
+	if (!copied)
+		copied = err;
+	else
+		*ppos += copied;
+	mutex_unlock(&seq->lock);
+	return copied;
+}
+
+static int iter_open(struct inode *inode, struct file *file)
+{
+	struct bpf_iter_link *link = inode->i_private;
+
+	return prepare_seq_file(file, link);
+}
+
+static int iter_release(struct inode *inode, struct file *file)
+{
+	struct bpf_iter_priv_data *iter_priv;
+	struct seq_file *seq;
+
+	seq = file->private_data;
+	if (!seq)
+		return 0;
+
+	iter_priv = container_of(seq->private, struct bpf_iter_priv_data,
+				 target_private);
+
+	if (iter_priv->tinfo->reg_info->fini_seq_private)
+		iter_priv->tinfo->reg_info->fini_seq_private(seq->private);
+
+	bpf_prog_put(iter_priv->prog);
+	seq->private = iter_priv;
+
+	return seq_release_private(inode, file);
+}
+
+const struct file_operations bpf_iter_fops = {
+	.open		= iter_open,
+	.llseek		= no_llseek,
+	.read		= bpf_seq_read,
+	.release	= iter_release,
+};
+
+/* The argument reg_info will be cached in bpf_iter_target_info.
+ * The common practice is to declare target reg_info as
+ * a const static variable and passed as an argument to
+ * bpf_iter_reg_target().
+ */
+int bpf_iter_reg_target(const struct bpf_iter_reg *reg_info)
+{
+	struct bpf_iter_target_info *tinfo;
+
+	tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
+	if (!tinfo)
+		return -ENOMEM;
+
+	tinfo->reg_info = reg_info;
+	INIT_LIST_HEAD(&tinfo->list);
+
+	mutex_lock(&targets_mutex);
+	list_add(&tinfo->list, &targets);
+	mutex_unlock(&targets_mutex);
+
+	return 0;
+}
+
+void bpf_iter_unreg_target(const struct bpf_iter_reg *reg_info)
+{
+	struct bpf_iter_target_info *tinfo;
+	bool found = false;
+
+	mutex_lock(&targets_mutex);
+	list_for_each_entry(tinfo, &targets, list) {
+		if (reg_info == tinfo->reg_info) {
+			list_del(&tinfo->list);
+			kfree(tinfo);
+			found = true;
+			break;
+		}
+	}
+	mutex_unlock(&targets_mutex);
+
+	WARN_ON(found == false);
+}
+
+static void cache_btf_id(struct bpf_iter_target_info *tinfo,
+			 struct bpf_prog *prog)
+{
+	tinfo->btf_id = prog->aux->attach_btf_id;
+}
+
+bool bpf_iter_prog_supported(struct bpf_prog *prog)
+{
+	const char *attach_fname = prog->aux->attach_func_name;
+	u32 prog_btf_id = prog->aux->attach_btf_id;
+	const char *prefix = BPF_ITER_FUNC_PREFIX;
+	struct bpf_iter_target_info *tinfo;
+	int prefix_len = strlen(prefix);
+	bool supported = false;
+
+	if (strncmp(attach_fname, prefix, prefix_len))
+		return false;
+
+	mutex_lock(&targets_mutex);
+	list_for_each_entry(tinfo, &targets, list) {
+		if (tinfo->btf_id && tinfo->btf_id == prog_btf_id) {
+			supported = true;
+			break;
+		}
+		if (!strcmp(attach_fname + prefix_len, tinfo->reg_info->target)) {
+			cache_btf_id(tinfo, prog);
+			supported = true;
+			break;
+		}
+	}
+	mutex_unlock(&targets_mutex);
+
+	if (supported) {
+		prog->aux->ctx_arg_info_size = tinfo->reg_info->ctx_arg_info_size;
+		prog->aux->ctx_arg_info = tinfo->reg_info->ctx_arg_info;
+	}
+
+	return supported;
+}
+
+static void bpf_iter_link_release(struct bpf_link *link)
+{
+}
+
+static void bpf_iter_link_dealloc(struct bpf_link *link)
+{
+	struct bpf_iter_link *iter_link =
+		container_of(link, struct bpf_iter_link, link);
+
+	kfree(iter_link);
+}
+
+static int bpf_iter_link_replace(struct bpf_link *link,
+				 struct bpf_prog *new_prog,
+				 struct bpf_prog *old_prog)
+{
+	int ret = 0;
+
+	mutex_lock(&link_mutex);
+	if (old_prog && link->prog != old_prog) {
+		ret = -EPERM;
+		goto out_unlock;
+	}
+
+	if (link->prog->type != new_prog->type ||
+	    link->prog->expected_attach_type != new_prog->expected_attach_type ||
+	    link->prog->aux->attach_btf_id != new_prog->aux->attach_btf_id) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	old_prog = xchg(&link->prog, new_prog);
+	bpf_prog_put(old_prog);
+
+out_unlock:
+	mutex_unlock(&link_mutex);
+	return ret;
+}
+
+static const struct bpf_link_ops bpf_iter_link_lops = {
+	.release = bpf_iter_link_release,
+	.dealloc = bpf_iter_link_dealloc,
+	.update_prog = bpf_iter_link_replace,
+};
+
+bool bpf_link_is_iter(struct bpf_link *link)
+{
+	return link->ops == &bpf_iter_link_lops;
+}
+
+int bpf_iter_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+	struct bpf_link_primer link_primer;
+	struct bpf_iter_target_info *tinfo;
+	struct bpf_iter_link *link;
+	bool existed = false;
+	u32 prog_btf_id;
+	int err;
+
+	if (attr->link_create.target_fd || attr->link_create.flags)
+		return -EINVAL;
+
+	prog_btf_id = prog->aux->attach_btf_id;
+	mutex_lock(&targets_mutex);
+	list_for_each_entry(tinfo, &targets, list) {
+		if (tinfo->btf_id == prog_btf_id) {
+			existed = true;
+			break;
+		}
+	}
+	mutex_unlock(&targets_mutex);
+	if (!existed)
+		return -ENOENT;
+
+	link = kzalloc(sizeof(*link), GFP_USER | __GFP_NOWARN);
+	if (!link)
+		return -ENOMEM;
+
+	bpf_link_init(&link->link, BPF_LINK_TYPE_ITER, &bpf_iter_link_lops, prog);
+	link->tinfo = tinfo;
+
+	err  = bpf_link_prime(&link->link, &link_primer);
+	if (err) {
+		kfree(link);
+		return err;
+	}
+
+	return bpf_link_settle(&link_primer);
+}
+
+static void init_seq_meta(struct bpf_iter_priv_data *priv_data,
+			  struct bpf_iter_target_info *tinfo,
+			  struct bpf_prog *prog)
+{
+	priv_data->tinfo = tinfo;
+	priv_data->prog = prog;
+	priv_data->session_id = atomic64_inc_return(&session_id);
+	priv_data->seq_num = 0;
+	priv_data->done_stop = false;
+}
+
+static int prepare_seq_file(struct file *file, struct bpf_iter_link *link)
+{
+	struct bpf_iter_priv_data *priv_data;
+	struct bpf_iter_target_info *tinfo;
+	struct bpf_prog *prog;
+	u32 total_priv_dsize;
+	struct seq_file *seq;
+	int err = 0;
+
+	mutex_lock(&link_mutex);
+	prog = link->link.prog;
+	bpf_prog_inc(prog);
+	mutex_unlock(&link_mutex);
+
+	tinfo = link->tinfo;
+	total_priv_dsize = offsetof(struct bpf_iter_priv_data, target_private) +
+			   tinfo->reg_info->seq_priv_size;
+	priv_data = __seq_open_private(file, tinfo->reg_info->seq_ops,
+				       total_priv_dsize);
+	if (!priv_data) {
+		err = -ENOMEM;
+		goto release_prog;
+	}
+
+	if (tinfo->reg_info->init_seq_private) {
+		err = tinfo->reg_info->init_seq_private(priv_data->target_private);
+		if (err)
+			goto release_seq_file;
+	}
+
+	init_seq_meta(priv_data, tinfo, prog);
+	seq = file->private_data;
+	seq->private = priv_data->target_private;
+
+	return 0;
+
+release_seq_file:
+	seq_release_private(file->f_inode, file);
+	file->private_data = NULL;
+release_prog:
+	bpf_prog_put(prog);
+	return err;
+}
+
+int bpf_iter_new_fd(struct bpf_link *link)
+{
+	struct file *file;
+	unsigned int flags;
+	int err, fd;
+
+	if (link->ops != &bpf_iter_link_lops)
+		return -EINVAL;
+
+	flags = O_RDONLY | O_CLOEXEC;
+	fd = get_unused_fd_flags(flags);
+	if (fd < 0)
+		return fd;
+
+	file = anon_inode_getfile("bpf_iter", &bpf_iter_fops, NULL, flags);
+	if (IS_ERR(file)) {
+		err = PTR_ERR(file);
+		goto free_fd;
+	}
+
+	err = prepare_seq_file(file,
+			       container_of(link, struct bpf_iter_link, link));
+	if (err)
+		goto free_file;
+
+	fd_install(fd, file);
+	return fd;
+
+free_file:
+	fput(file);
+free_fd:
+	put_unused_fd(fd);
+	return err;
+}
+
+struct bpf_prog *bpf_iter_get_info(struct bpf_iter_meta *meta, bool in_stop)
+{
+	struct bpf_iter_priv_data *iter_priv;
+	struct seq_file *seq;
+	void *seq_priv;
+
+	seq = meta->seq;
+	if (seq->file->f_op != &bpf_iter_fops)
+		return NULL;
+
+	seq_priv = seq->private;
+	iter_priv = container_of(seq_priv, struct bpf_iter_priv_data,
+				 target_private);
+
+	if (in_stop && iter_priv->done_stop)
+		return NULL;
+
+	meta->session_id = iter_priv->session_id;
+	meta->seq_num = iter_priv->seq_num;
+
+	return iter_priv->prog;
+}
+
+int bpf_iter_run_prog(struct bpf_prog *prog, void *ctx)
+{
+	int ret;
+
+	rcu_read_lock();
+	migrate_disable();
+	ret = BPF_PROG_RUN(prog, ctx);
+	migrate_enable();
+	rcu_read_unlock();
+
+	/* bpf program can only return 0 or 1:
+	 *  0 : okay
+	 *  1 : retry the same object
+	 * The bpf_iter_run_prog() return value
+	 * will be seq_ops->show() return value.
+	 */
+	return ret == 0 ? 0 : -EAGAIN;
+}
diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index 26cb51f2db72..c6b0decaa46a 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -557,7 +557,7 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
 	struct bpf_map *map;
 	int err;
 
-	if (!capable(CAP_SYS_ADMIN))
+	if (!bpf_capable())
 		return ERR_PTR(-EPERM);
 
 	st_ops = bpf_struct_ops_find_value(attr->btf_vmlinux_value_type_id);
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index d65c6912bdaf..58c9af1d4808 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -3482,6 +3482,7 @@ extern char __weak __stop_BTF[];
 extern struct btf *btf_vmlinux;
 
 #define BPF_MAP_TYPE(_id, _ops)
+#define BPF_LINK_TYPE(_id, _name)
 static union {
 	struct bpf_ctx_convert {
 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
@@ -3508,6 +3509,7 @@ static u8 bpf_ctx_convert_map[] = {
 	0, /* avoid empty array */
 };
 #undef BPF_MAP_TYPE
+#undef BPF_LINK_TYPE
 
 static const struct btf_member *
 btf_get_prog_ctx_type(struct bpf_verifier_log *log, struct btf *btf,
@@ -3692,7 +3694,7 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type,
 	struct bpf_verifier_log *log = info->log;
 	const struct btf_param *args;
 	u32 nr_args, arg;
-	int ret;
+	int i, ret;
 
 	if (off % 8) {
 		bpf_log(log, "func '%s' offset %d is not multiple of 8\n",
@@ -3789,6 +3791,14 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type,
 
 	/* this is a pointer to another type */
 	info->reg_type = PTR_TO_BTF_ID;
+	for (i = 0; i < prog->aux->ctx_arg_info_size; i++) {
+		const struct bpf_ctx_arg_aux *ctx_arg_info = &prog->aux->ctx_arg_info[i];
+
+		if (ctx_arg_info->offset == off) {
+			info->reg_type = ctx_arg_info->reg_type;
+			break;
+		}
+	}
 
 	if (tgt_prog) {
 		ret = btf_translate_to_vmlinux(log, btf, t, tgt_prog->type, arg);
@@ -3828,6 +3838,7 @@ int btf_struct_access(struct bpf_verifier_log *log,
 	const struct btf_type *mtype, *elem_type = NULL;
 	const struct btf_member *member;
 	const char *tname, *mname;
+	u32 vlen;
 
 again:
 	tname = __btf_name_by_offset(btf_vmlinux, t->name_off);
@@ -3836,7 +3847,43 @@ again:
 		return -EINVAL;
 	}
 
+	vlen = btf_type_vlen(t);
 	if (off + size > t->size) {
+		/* If the last element is a variable size array, we may
+		 * need to relax the rule.
+		 */
+		struct btf_array *array_elem;
+
+		if (vlen == 0)
+			goto error;
+
+		member = btf_type_member(t) + vlen - 1;
+		mtype = btf_type_skip_modifiers(btf_vmlinux, member->type,
+						NULL);
+		if (!btf_type_is_array(mtype))
+			goto error;
+
+		array_elem = (struct btf_array *)(mtype + 1);
+		if (array_elem->nelems != 0)
+			goto error;
+
+		moff = btf_member_bit_offset(t, member) / 8;
+		if (off < moff)
+			goto error;
+
+		/* Only allow structure for now, can be relaxed for
+		 * other types later.
+		 */
+		elem_type = btf_type_skip_modifiers(btf_vmlinux,
+						    array_elem->type, NULL);
+		if (!btf_type_is_struct(elem_type))
+			goto error;
+
+		off = (off - moff) % elem_type->size;
+		return btf_struct_access(log, elem_type, off, size, atype,
+					 next_btf_id);
+
+error:
 		bpf_log(log, "access beyond struct %s at off %u size %u\n",
 			tname, off, size);
 		return -EACCES;
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index cb305e71e7de..5c0e964105ac 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -557,8 +557,9 @@ found:
  *
  * Must be called with cgroup_mutex held.
  */
-int __cgroup_bpf_replace(struct cgroup *cgrp, struct bpf_cgroup_link *link,
-			 struct bpf_prog *new_prog)
+static int __cgroup_bpf_replace(struct cgroup *cgrp,
+				struct bpf_cgroup_link *link,
+				struct bpf_prog *new_prog)
 {
 	struct list_head *progs = &cgrp->bpf.progs[link->type];
 	struct bpf_prog *old_prog;
@@ -583,6 +584,30 @@ int __cgroup_bpf_replace(struct cgroup *cgrp, struct bpf_cgroup_link *link,
 	return 0;
 }
 
+static int cgroup_bpf_replace(struct bpf_link *link, struct bpf_prog *new_prog,
+			      struct bpf_prog *old_prog)
+{
+	struct bpf_cgroup_link *cg_link;
+	int ret;
+
+	cg_link = container_of(link, struct bpf_cgroup_link, link);
+
+	mutex_lock(&cgroup_mutex);
+	/* link might have been auto-released by dying cgroup, so fail */
+	if (!cg_link->cgroup) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	if (old_prog && link->prog != old_prog) {
+		ret = -EPERM;
+		goto out_unlock;
+	}
+	ret = __cgroup_bpf_replace(cg_link->cgroup, cg_link, new_prog);
+out_unlock:
+	mutex_unlock(&cgroup_mutex);
+	return ret;
+}
+
 static struct bpf_prog_list *find_detach_entry(struct list_head *progs,
 					       struct bpf_prog *prog,
 					       struct bpf_cgroup_link *link,
@@ -808,17 +833,56 @@ static void bpf_cgroup_link_dealloc(struct bpf_link *link)
 	kfree(cg_link);
 }
 
-const struct bpf_link_ops bpf_cgroup_link_lops = {
+static void bpf_cgroup_link_show_fdinfo(const struct bpf_link *link,
+					struct seq_file *seq)
+{
+	struct bpf_cgroup_link *cg_link =
+		container_of(link, struct bpf_cgroup_link, link);
+	u64 cg_id = 0;
+
+	mutex_lock(&cgroup_mutex);
+	if (cg_link->cgroup)
+		cg_id = cgroup_id(cg_link->cgroup);
+	mutex_unlock(&cgroup_mutex);
+
+	seq_printf(seq,
+		   "cgroup_id:\t%llu\n"
+		   "attach_type:\t%d\n",
+		   cg_id,
+		   cg_link->type);
+}
+
+static int bpf_cgroup_link_fill_link_info(const struct bpf_link *link,
+					  struct bpf_link_info *info)
+{
+	struct bpf_cgroup_link *cg_link =
+		container_of(link, struct bpf_cgroup_link, link);
+	u64 cg_id = 0;
+
+	mutex_lock(&cgroup_mutex);
+	if (cg_link->cgroup)
+		cg_id = cgroup_id(cg_link->cgroup);
+	mutex_unlock(&cgroup_mutex);
+
+	info->cgroup.cgroup_id = cg_id;
+	info->cgroup.attach_type = cg_link->type;
+	return 0;
+}
+
+static const struct bpf_link_ops bpf_cgroup_link_lops = {
 	.release = bpf_cgroup_link_release,
 	.dealloc = bpf_cgroup_link_dealloc,
+	.update_prog = cgroup_bpf_replace,
+	.show_fdinfo = bpf_cgroup_link_show_fdinfo,
+	.fill_link_info = bpf_cgroup_link_fill_link_info,
 };
 
 int cgroup_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
 {
+	struct bpf_link_primer link_primer;
 	struct bpf_cgroup_link *link;
-	struct file *link_file;
 	struct cgroup *cgrp;
-	int err, link_fd;
+	int err;
 
 	if (attr->link_create.flags)
 		return -EINVAL;
@@ -832,26 +896,25 @@ int cgroup_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
 		err = -ENOMEM;
 		goto out_put_cgroup;
 	}
-	bpf_link_init(&link->link, &bpf_cgroup_link_lops, prog);
+	bpf_link_init(&link->link, BPF_LINK_TYPE_CGROUP, &bpf_cgroup_link_lops,
+		      prog);
 	link->cgroup = cgrp;
 	link->type = attr->link_create.attach_type;
 
-	link_file = bpf_link_new_file(&link->link, &link_fd);
-	if (IS_ERR(link_file)) {
+	err  = bpf_link_prime(&link->link, &link_primer);
+	if (err) {
 		kfree(link);
-		err = PTR_ERR(link_file);
 		goto out_put_cgroup;
 	}
 
 	err = cgroup_bpf_attach(cgrp, NULL, NULL, link, link->type,
 				BPF_F_ALLOW_MULTI);
 	if (err) {
-		bpf_link_cleanup(&link->link, link_file, link_fd);
+		bpf_link_cleanup(&link_primer);
 		goto out_put_cgroup;
 	}
 
-	fd_install(link_fd, link_file);
-	return link_fd;
+	return bpf_link_settle(&link_primer);
 
 out_put_cgroup:
 	cgroup_put(cgrp);
@@ -1054,36 +1117,21 @@ int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
 
 	return !allow;
 }
-EXPORT_SYMBOL(__cgroup_bpf_check_dev_permission);
 
 static const struct bpf_func_proto *
 cgroup_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
 	switch (func_id) {
-	case BPF_FUNC_map_lookup_elem:
-		return &bpf_map_lookup_elem_proto;
-	case BPF_FUNC_map_update_elem:
-		return &bpf_map_update_elem_proto;
-	case BPF_FUNC_map_delete_elem:
-		return &bpf_map_delete_elem_proto;
-	case BPF_FUNC_map_push_elem:
-		return &bpf_map_push_elem_proto;
-	case BPF_FUNC_map_pop_elem:
-		return &bpf_map_pop_elem_proto;
-	case BPF_FUNC_map_peek_elem:
-		return &bpf_map_peek_elem_proto;
 	case BPF_FUNC_get_current_uid_gid:
 		return &bpf_get_current_uid_gid_proto;
 	case BPF_FUNC_get_local_storage:
 		return &bpf_get_local_storage_proto;
 	case BPF_FUNC_get_current_cgroup_id:
 		return &bpf_get_current_cgroup_id_proto;
-	case BPF_FUNC_trace_printk:
-		if (capable(CAP_SYS_ADMIN))
-			return bpf_get_trace_printk_proto();
-		/* fall through */
+	case BPF_FUNC_perf_event_output:
+		return &bpf_event_output_data_proto;
 	default:
-		return NULL;
+		return bpf_base_func_proto(func_id);
 	}
 }
 
@@ -1137,16 +1185,13 @@ const struct bpf_verifier_ops cg_dev_verifier_ops = {
  * @head: sysctl table header
  * @table: sysctl table
  * @write: sysctl is being read (= 0) or written (= 1)
- * @buf: pointer to buffer passed by user space
+ * @buf: pointer to buffer (in and out)
  * @pcount: value-result argument: value is size of buffer pointed to by @buf,
  *	result is size of @new_buf if program set new value, initial value
  *	otherwise
  * @ppos: value-result argument: value is position at which read from or write
  *	to sysctl is happening, result is new position if program overrode it,
  *	initial value otherwise
- * @new_buf: pointer to pointer to new buffer that will be allocated if program
- *	overrides new value provided by user space on sysctl write
- *	NOTE: it's caller responsibility to free *new_buf if it was set
  * @type: type of program to be executed
  *
  * Program is run when sysctl is being accessed, either read or written, and
@@ -1157,8 +1202,7 @@ const struct bpf_verifier_ops cg_dev_verifier_ops = {
  */
 int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
 				   struct ctl_table *table, int write,
-				   void __user *buf, size_t *pcount,
-				   loff_t *ppos, void **new_buf,
+				   void **buf, size_t *pcount, loff_t *ppos,
 				   enum bpf_attach_type type)
 {
 	struct bpf_sysctl_kern ctx = {
@@ -1173,36 +1217,28 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
 		.new_updated = 0,
 	};
 	struct cgroup *cgrp;
+	loff_t pos = 0;
 	int ret;
 
 	ctx.cur_val = kmalloc_track_caller(ctx.cur_len, GFP_KERNEL);
-	if (ctx.cur_val) {
-		mm_segment_t old_fs;
-		loff_t pos = 0;
-
-		old_fs = get_fs();
-		set_fs(KERNEL_DS);
-		if (table->proc_handler(table, 0, (void __user *)ctx.cur_val,
-					&ctx.cur_len, &pos)) {
-			/* Let BPF program decide how to proceed. */
-			ctx.cur_len = 0;
-		}
-		set_fs(old_fs);
-	} else {
+	if (!ctx.cur_val ||
+	    table->proc_handler(table, 0, ctx.cur_val, &ctx.cur_len, &pos)) {
 		/* Let BPF program decide how to proceed. */
 		ctx.cur_len = 0;
 	}
 
-	if (write && buf && *pcount) {
+	if (write && *buf && *pcount) {
 		/* BPF program should be able to override new value with a
 		 * buffer bigger than provided by user.
 		 */
 		ctx.new_val = kmalloc_track_caller(PAGE_SIZE, GFP_KERNEL);
 		ctx.new_len = min_t(size_t, PAGE_SIZE, *pcount);
-		if (!ctx.new_val ||
-		    copy_from_user(ctx.new_val, buf, ctx.new_len))
+		if (ctx.new_val) {
+			memcpy(ctx.new_val, *buf, ctx.new_len);
+		} else {
 			/* Let BPF program decide how to proceed. */<