firmware/br-ext-chip-allwinner/board/v83x/kernel/patches/00000-kernel_bpf_syscall.c.patch

diff -drupN a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
--- a/kernel/bpf/syscall.c	2018-08-06 17:23:04.000000000 +0300
+++ b/kernel/bpf/syscall.c	2022-06-12 05:28:14.000000000 +0300
@@ -20,6 +20,8 @@
 #include <linux/filter.h>
 #include <linux/version.h>
 
+#define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
+
 DEFINE_PER_CPU(int, bpf_prog_active);
 
 int sysctl_unprivileged_bpf_disabled __read_mostly;
@@ -119,6 +121,7 @@ static void bpf_map_free_deferred(struct
 	struct bpf_map *map = container_of(work, struct bpf_map, work);
 
 	bpf_map_uncharge_memlock(map);
+	security_bpf_map_free(map);
 	/* implementation dependent freeing */
 	map->ops->map_free(map);
 }
@@ -178,17 +181,54 @@ static void bpf_map_show_fdinfo(struct s
 }
 #endif
 
-static const struct file_operations bpf_map_fops = {
+static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
+			      loff_t *ppos)
+{
+	/* We need this handler such that alloc_file() enables
+	 * f_mode with FMODE_CAN_READ.
+	 */
+	return -EINVAL;
+}
+
+static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
+			       size_t siz, loff_t *ppos)
+{
+	/* We need this handler such that alloc_file() enables
+	 * f_mode with FMODE_CAN_WRITE.
+	 */
+	return -EINVAL;
+}
+
+const struct file_operations bpf_map_fops = {
 #ifdef CONFIG_PROC_FS
 	.show_fdinfo	= bpf_map_show_fdinfo,
 #endif
 	.release	= bpf_map_release,
+	.read		= bpf_dummy_read,
+	.write		= bpf_dummy_write,
 };
 
-int bpf_map_new_fd(struct bpf_map *map)
+int bpf_map_new_fd(struct bpf_map *map, int flags)
 {
+	int ret;
+
+	ret = security_bpf_map(map, OPEN_FMODE(flags));
+	if (ret < 0)
+		return ret;
+
 	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
-				O_RDWR | O_CLOEXEC);
+				flags | O_CLOEXEC);
+}
+
+int bpf_get_file_flag(int flags)
+{
+	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
+		return -EINVAL;
+	if (flags & BPF_F_RDONLY)
+		return O_RDONLY;
+	if (flags & BPF_F_WRONLY)
+		return O_WRONLY;
+	return O_RDWR;
 }
 
 /* helper macro to check that unused fields 'union bpf_attr' are zero */
@@ -204,12 +244,17 @@ int bpf_map_new_fd(struct bpf_map *map)
 static int map_create(union bpf_attr *attr)
 {
 	struct bpf_map *map;
+	int f_flags;
 	int err;
 
 	err = CHECK_ATTR(BPF_MAP_CREATE);
 	if (err)
 		return -EINVAL;
 
+	f_flags = bpf_get_file_flag(attr->map_flags);
+	if (f_flags < 0)
+		return f_flags;
+
 	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
 	map = find_and_alloc_map(attr);
 	if (IS_ERR(map))
@@ -218,11 +263,15 @@ static int map_create(union bpf_attr *at
 	atomic_set(&map->refcnt, 1);
 	atomic_set(&map->usercnt, 1);
 
-	err = bpf_map_charge_memlock(map);
+	err = security_bpf_map_alloc(map);
 	if (err)
 		goto free_map_nouncharge;
 
-	err = bpf_map_new_fd(map);
+	err = bpf_map_charge_memlock(map);
+	if (err)
+		goto free_map_sec;
+
+	err = bpf_map_new_fd(map, f_flags);
 	if (err < 0)
 		/* failed to allocate fd */
 		goto free_map;
@@ -231,6 +280,8 @@ static int map_create(union bpf_attr *at
 
 free_map:
 	bpf_map_uncharge_memlock(map);
+free_map_sec:
+	security_bpf_map_free(map);
 free_map_nouncharge:
 	map->ops->map_free(map);
 	return err;
@@ -313,6 +364,11 @@ static int map_lookup_elem(union bpf_att
 	if (IS_ERR(map))
 		return PTR_ERR(map);
 
+	if (!(f.file->f_mode & FMODE_CAN_READ)) {
+		err = -EPERM;
+		goto err_put;
+	}
+
 	err = -ENOMEM;
 	key = kmalloc(map->key_size, GFP_USER);
 	if (!key)
@@ -387,6 +443,11 @@ static int map_update_elem(union bpf_att
 	if (IS_ERR(map))
 		return PTR_ERR(map);
 
+	if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
+		err = -EPERM;
+		goto err_put;
+	}
+
 	err = -ENOMEM;
 	key = kmalloc(map->key_size, GFP_USER);
 	if (!key)
@@ -463,6 +524,11 @@ static int map_delete_elem(union bpf_att
 	if (IS_ERR(map))
 		return PTR_ERR(map);
 
+	if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
+		err = -EPERM;
+		goto err_put;
+	}
+
 	err = -ENOMEM;
 	key = kmalloc(map->key_size, GFP_USER);
 	if (!key)
@@ -508,6 +574,11 @@ static int map_get_next_key(union bpf_at
 	if (IS_ERR(map))
 		return PTR_ERR(map);
 
+	if (!(f.file->f_mode & FMODE_CAN_READ)) {
+		err = -EPERM;
+		goto err_put;
+	}
+
 	if (ukey) {
 		err = -ENOMEM;
 		key = kmalloc(map->key_size, GFP_USER);
@@ -611,6 +682,7 @@ static void __bpf_prog_put_rcu(struct rc
 
 	free_used_maps(aux);
 	bpf_prog_uncharge_memlock(aux->prog);
+	security_bpf_prog_free(aux);
 	bpf_prog_free(aux->prog);
 }
 
@@ -629,12 +701,20 @@ static int bpf_prog_release(struct inode
 	return 0;
 }
 
-static const struct file_operations bpf_prog_fops = {
+const struct file_operations bpf_prog_fops = {
         .release = bpf_prog_release,
+	.read		= bpf_dummy_read,
+	.write		= bpf_dummy_write,
 };
 
 int bpf_prog_new_fd(struct bpf_prog *prog)
 {
+	int ret;
+
+	ret = security_bpf_prog(prog);
+	if (ret < 0)
+		return ret;
+
 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
 				O_RDWR | O_CLOEXEC);
 }
@@ -726,7 +806,9 @@ static int bpf_prog_load(union bpf_attr
 	    attr->kern_version != LINUX_VERSION_CODE)
 		return -EINVAL;
 
-	if (type != BPF_PROG_TYPE_SOCKET_FILTER && !capable(CAP_SYS_ADMIN))
+	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
+	    type != BPF_PROG_TYPE_CGROUP_SKB &&
+	    !capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
 	/* plain bpf_prog allocation */
@@ -734,10 +816,14 @@ static int bpf_prog_load(union bpf_attr
 	if (!prog)
 		return -ENOMEM;
 
-	err = bpf_prog_charge_memlock(prog);
+	err = security_bpf_prog_alloc(prog->aux);
 	if (err)
 		goto free_prog_nouncharge;
 
+	err = bpf_prog_charge_memlock(prog);
+	if (err)
+		goto free_prog_sec;
+
 	prog->len = attr->insn_cnt;
 
 	err = -EFAULT;
@@ -777,16 +863,18 @@ free_used_maps:
 	free_used_maps(prog->aux);
 free_prog:
 	bpf_prog_uncharge_memlock(prog);
+free_prog_sec:
+	security_bpf_prog_free(prog->aux);
 free_prog_nouncharge:
 	bpf_prog_free(prog);
 	return err;
 }
 
-#define BPF_OBJ_LAST_FIELD bpf_fd
+#define BPF_OBJ_LAST_FIELD file_flags
 
 static int bpf_obj_pin(const union bpf_attr *attr)
 {
-	if (CHECK_ATTR(BPF_OBJ))
+	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
 		return -EINVAL;
 
 	return bpf_obj_pin_user(attr->bpf_fd, u64_to_ptr(attr->pathname));
@@ -794,12 +882,93 @@ static int bpf_obj_pin(const union bpf_a
 
 static int bpf_obj_get(const union bpf_attr *attr)
 {
-	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0)
+	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
+	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
 		return -EINVAL;
 
-	return bpf_obj_get_user(u64_to_ptr(attr->pathname));
+	return bpf_obj_get_user(u64_to_ptr(attr->pathname),
+				attr->file_flags);
 }
 
+#ifdef CONFIG_CGROUP_BPF
+
+#define BPF_PROG_ATTACH_LAST_FIELD attach_flags
+
+static int bpf_prog_attach(const union bpf_attr *attr)
+{
+	struct bpf_prog *prog;
+	struct cgroup *cgrp;
+	int ret;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (CHECK_ATTR(BPF_PROG_ATTACH))
+		return -EINVAL;
+
+	if (attr->attach_flags & ~BPF_F_ALLOW_OVERRIDE)
+		return -EINVAL;
+
+	switch (attr->attach_type) {
+	case BPF_CGROUP_INET_INGRESS:
+	case BPF_CGROUP_INET_EGRESS:
+		prog = bpf_prog_get_type(attr->attach_bpf_fd,
+					 BPF_PROG_TYPE_CGROUP_SKB);
+		if (IS_ERR(prog))
+			return PTR_ERR(prog);
+
+		cgrp = cgroup_get_from_fd(attr->target_fd);
+		if (IS_ERR(cgrp)) {
+			bpf_prog_put(prog);
+			return PTR_ERR(cgrp);
+		}
+
+		ret = cgroup_bpf_update(cgrp, prog, attr->attach_type,
+					attr->attach_flags & BPF_F_ALLOW_OVERRIDE);
+		if (ret)
+			bpf_prog_put(prog);
+		cgroup_put(cgrp);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+#define BPF_PROG_DETACH_LAST_FIELD attach_type
+
+static int bpf_prog_detach(const union bpf_attr *attr)
+{
+	struct cgroup *cgrp;
+	int ret;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (CHECK_ATTR(BPF_PROG_DETACH))
+		return -EINVAL;
+
+	switch (attr->attach_type) {
+	case BPF_CGROUP_INET_INGRESS:
+	case BPF_CGROUP_INET_EGRESS:
+		cgrp = cgroup_get_from_fd(attr->target_fd);
+		if (IS_ERR(cgrp))
+			return PTR_ERR(cgrp);
+
+		ret = cgroup_bpf_update(cgrp, NULL, attr->attach_type, false);
+		cgroup_put(cgrp);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return ret;
+}
+#endif /* CONFIG_CGROUP_BPF */
+
 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
 {
 	union bpf_attr attr = {};
@@ -841,6 +1010,10 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf
 	if (copy_from_user(&attr, uattr, size) != 0)
 		return -EFAULT;
 
+	err = security_bpf(cmd, &attr, size);
+	if (err < 0)
+		return err;
+
 	switch (cmd) {
 	case BPF_MAP_CREATE:
 		err = map_create(&attr);
@@ -866,6 +1039,16 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf
 	case BPF_OBJ_GET:
 		err = bpf_obj_get(&attr);
 		break;
+
+#ifdef CONFIG_CGROUP_BPF
+	case BPF_PROG_ATTACH:
+		err = bpf_prog_attach(&attr);
+		break;
+	case BPF_PROG_DETACH:
+		err = bpf_prog_detach(&attr);
+		break;
+#endif
+
 	default:
 		err = -EINVAL;
 		break;