1 files changed, 215 insertions, 115 deletions

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index f00c00b942df..64783da34202 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -25,6 +25,7 @@
 #include <linux/nospec.h>
 #include <linux/audit.h>
 #include <uapi/linux/btf.h>
+#include <linux/bpf_lsm.h>
 
 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
 			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
@@ -1942,6 +1943,7 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
 
 		switch (prog_type) {
 		case BPF_PROG_TYPE_TRACING:
+		case BPF_PROG_TYPE_LSM:
 		case BPF_PROG_TYPE_STRUCT_OPS:
 		case BPF_PROG_TYPE_EXT:
 			break;
@@ -2181,13 +2183,6 @@ static int bpf_obj_get(const union bpf_attr *attr)
 				attr->file_flags);
 }
 
-struct bpf_link {
-	atomic64_t refcnt;
-	const struct bpf_link_ops *ops;
-	struct bpf_prog *prog;
-	struct work_struct work;
-};
-
 void bpf_link_init(struct bpf_link *link, const struct bpf_link_ops *ops,
 		   struct bpf_prog *prog)
 {
@@ -2201,8 +2196,8 @@ void bpf_link_init(struct bpf_link *link, const struct bpf_link_ops *ops,
  * anon_inode's release() call. This helper manages marking bpf_link as
  * defunct, releases anon_inode file and puts reserved FD.
  */
-static void bpf_link_cleanup(struct bpf_link *link, struct file *link_file,
-			     int link_fd)
+void bpf_link_cleanup(struct bpf_link *link, struct file *link_file,
+		      int link_fd)
 {
 	link->prog = NULL;
 	fput(link_file);
@@ -2260,7 +2255,6 @@ static int bpf_link_release(struct inode *inode, struct file *filp)
 #ifdef CONFIG_PROC_FS
 static const struct bpf_link_ops bpf_raw_tp_lops;
 static const struct bpf_link_ops bpf_tracing_link_lops;
-static const struct bpf_link_ops bpf_xdp_link_lops;
 
 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
 {
@@ -2273,6 +2267,10 @@ static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
 		link_type = "raw_tracepoint";
 	else if (link->ops == &bpf_tracing_link_lops)
 		link_type = "tracing";
+#ifdef CONFIG_CGROUP_BPF
+	else if (link->ops == &bpf_cgroup_link_lops)
+		link_type = "cgroup";
+#endif
 	else
 		link_type = "unknown";
 
@@ -2375,10 +2373,28 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog)
 	struct file *link_file;
 	int link_fd, err;
 
-	if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
-	    prog->expected_attach_type != BPF_TRACE_FEXIT &&
-	    prog->expected_attach_type != BPF_MODIFY_RETURN &&
-	    prog->type != BPF_PROG_TYPE_EXT) {
+	switch (prog->type) {
+	case BPF_PROG_TYPE_TRACING:
+		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
+		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
+		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
+			err = -EINVAL;
+			goto out_put_prog;
+		}
+		break;
+	case BPF_PROG_TYPE_EXT:
+		if (prog->expected_attach_type != 0) {
+			err = -EINVAL;
+			goto out_put_prog;
+		}
+		break;
+	case BPF_PROG_TYPE_LSM:
+		if (prog->expected_attach_type != BPF_LSM_MAC) {
+			err = -EINVAL;
+			goto out_put_prog;
+		}
+		break;
+	default:
 		err = -EINVAL;
 		goto out_put_prog;
 	}
@@ -2457,16 +2473,10 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
 	if (IS_ERR(prog))
 		return PTR_ERR(prog);
 
-	if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
-	    prog->type != BPF_PROG_TYPE_TRACING &&
-	    prog->type != BPF_PROG_TYPE_EXT &&
-	    prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
-		err = -EINVAL;
-		goto out_put_prog;
-	}
-
-	if (prog->type == BPF_PROG_TYPE_TRACING ||
-	    prog->type == BPF_PROG_TYPE_EXT) {
+	switch (prog->type) {
+	case BPF_PROG_TYPE_TRACING:
+	case BPF_PROG_TYPE_EXT:
+	case BPF_PROG_TYPE_LSM:
 		if (attr->raw_tracepoint.name) {
 			/* The attach point for this category of programs
 			 * should be specified via btf_id during program load.
@@ -2474,11 +2484,14 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
 			err = -EINVAL;
 			goto out_put_prog;
 		}
-		if (prog->expected_attach_type == BPF_TRACE_RAW_TP)
+		if (prog->type == BPF_PROG_TYPE_TRACING &&
+		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
 			tp_name = prog->aux->attach_func_name;
-		else
-			return bpf_tracing_prog_attach(prog);
-	} else {
+			break;
+		}
+		return bpf_tracing_prog_attach(prog);
+	case BPF_PROG_TYPE_RAW_TRACEPOINT:
+	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
 		if (strncpy_from_user(buf,
 				      u64_to_user_ptr(attr->raw_tracepoint.name),
 				      sizeof(buf) - 1) < 0) {
@@ -2487,6 +2500,10 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
 		}
 		buf[sizeof(buf) - 1] = 0;
 		tp_name = buf;
+		break;
+	default:
+		err = -EINVAL;
+		goto out_put_prog;
 	}
 
 	btp = bpf_get_raw_tracepoint(tp_name);
@@ -2543,36 +2560,18 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
 	}
 }
 
-#define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
-
-#define BPF_F_ATTACH_MASK \
-	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
-
-static int bpf_prog_attach(const union bpf_attr *attr)
+static enum bpf_prog_type
+attach_type_to_prog_type(enum bpf_attach_type attach_type)
 {
-	enum bpf_prog_type ptype;
-	struct bpf_prog *prog;
-	int ret;
-
-	if (!capable(CAP_NET_ADMIN))
-		return -EPERM;
-
-	if (CHECK_ATTR(BPF_PROG_ATTACH))
-		return -EINVAL;
-
-	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
-		return -EINVAL;
-
-	switch (attr->attach_type) {
+	switch (attach_type) {
 	case BPF_CGROUP_INET_INGRESS:
 	case BPF_CGROUP_INET_EGRESS:
-		ptype = BPF_PROG_TYPE_CGROUP_SKB;
+		return BPF_PROG_TYPE_CGROUP_SKB;
 		break;
 	case BPF_CGROUP_INET_SOCK_CREATE:
 	case BPF_CGROUP_INET4_POST_BIND:
 	case BPF_CGROUP_INET6_POST_BIND:
-		ptype = BPF_PROG_TYPE_CGROUP_SOCK;
-		break;
+		return BPF_PROG_TYPE_CGROUP_SOCK;
 	case BPF_CGROUP_INET4_BIND:
 	case BPF_CGROUP_INET6_BIND:
 	case BPF_CGROUP_INET4_CONNECT:
@@ -2581,37 +2580,53 @@ static int bpf_prog_attach(const union bpf_attr *attr)
 	case BPF_CGROUP_UDP6_SENDMSG:
 	case BPF_CGROUP_UDP4_RECVMSG:
 	case BPF_CGROUP_UDP6_RECVMSG:
-		ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
-		break;
+		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
 	case BPF_CGROUP_SOCK_OPS:
-		ptype = BPF_PROG_TYPE_SOCK_OPS;
-		break;
+		return BPF_PROG_TYPE_SOCK_OPS;
 	case BPF_CGROUP_DEVICE:
-		ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
-		break;
+		return BPF_PROG_TYPE_CGROUP_DEVICE;
 	case BPF_SK_MSG_VERDICT:
-		ptype = BPF_PROG_TYPE_SK_MSG;
-		break;
+		return BPF_PROG_TYPE_SK_MSG;
 	case BPF_SK_SKB_STREAM_PARSER:
 	case BPF_SK_SKB_STREAM_VERDICT:
-		ptype = BPF_PROG_TYPE_SK_SKB;
-		break;
+		return BPF_PROG_TYPE_SK_SKB;
 	case BPF_LIRC_MODE2:
-		ptype = BPF_PROG_TYPE_LIRC_MODE2;
-		break;
+		return BPF_PROG_TYPE_LIRC_MODE2;
 	case BPF_FLOW_DISSECTOR:
-		ptype = BPF_PROG_TYPE_FLOW_DISSECTOR;
-		break;
+		return BPF_PROG_TYPE_FLOW_DISSECTOR;
 	case BPF_CGROUP_SYSCTL:
-		ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
-		break;
+		return BPF_PROG_TYPE_CGROUP_SYSCTL;
 	case BPF_CGROUP_GETSOCKOPT:
 	case BPF_CGROUP_SETSOCKOPT:
-		ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
-		break;
+		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
 	default:
-		return -EINVAL;
+		return BPF_PROG_TYPE_UNSPEC;
 	}
+}
+
+#define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
+
+#define BPF_F_ATTACH_MASK \
+	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
+
+static int bpf_prog_attach(const union bpf_attr *attr)
+{
+	enum bpf_prog_type ptype;
+	struct bpf_prog *prog;
+	int ret;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (CHECK_ATTR(BPF_PROG_ATTACH))
+		return -EINVAL;
+
+	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
+		return -EINVAL;
+
+	ptype = attach_type_to_prog_type(attr->attach_type);
+	if (ptype == BPF_PROG_TYPE_UNSPEC)
+		return -EINVAL;
 
 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
 	if (IS_ERR(prog))
@@ -2633,8 +2648,17 @@ static int bpf_prog_attach(const union bpf_attr *attr)
 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
 		ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
 		break;
-	default:
+	case BPF_PROG_TYPE_CGROUP_DEVICE:
+	case BPF_PROG_TYPE_CGROUP_SKB:
+	case BPF_PROG_TYPE_CGROUP_SOCK:
+	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+	case BPF_PROG_TYPE_CGROUP_SYSCTL:
+	case BPF_PROG_TYPE_SOCK_OPS:
 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
+		break;
+	default:
+		ret = -EINVAL;
 	}
 
 	if (ret)
@@ -2654,53 +2678,27 @@ static int bpf_prog_detach(const union bpf_attr *attr)
 	if (CHECK_ATTR(BPF_PROG_DETACH))
 		return -EINVAL;
 
-	switch (attr->attach_type) {
-	case BPF_CGROUP_INET_INGRESS:
-	case BPF_CGROUP_INET_EGRESS:
-		ptype = BPF_PROG_TYPE_CGROUP_SKB;
-		break;
-	case BPF_CGROUP_INET_SOCK_CREATE:
-	case BPF_CGROUP_INET4_POST_BIND:
-	case BPF_CGROUP_INET6_POST_BIND:
-		ptype = BPF_PROG_TYPE_CGROUP_SOCK;
-		break;
-	case BPF_CGROUP_INET4_BIND:
-	case BPF_CGROUP_INET6_BIND:
-	case BPF_CGROUP_INET4_CONNECT:
-	case BPF_CGROUP_INET6_CONNECT:
-	case BPF_CGROUP_UDP4_SENDMSG:
-	case BPF_CGROUP_UDP6_SENDMSG:
-	case BPF_CGROUP_UDP4_RECVMSG:
-	case BPF_CGROUP_UDP6_RECVMSG:
-		ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
-		break;
-	case BPF_CGROUP_SOCK_OPS:
-		ptype = BPF_PROG_TYPE_SOCK_OPS;
-		break;
-	case BPF_CGROUP_DEVICE:
-		ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
-		break;
-	case BPF_SK_MSG_VERDICT:
-		return sock_map_get_from_fd(attr, NULL);
-	case BPF_SK_SKB_STREAM_PARSER:
-	case BPF_SK_SKB_STREAM_VERDICT:
+	ptype = attach_type_to_prog_type(attr->attach_type);
+
+	switch (ptype) {
+	case BPF_PROG_TYPE_SK_MSG:
+	case BPF_PROG_TYPE_SK_SKB:
 		return sock_map_get_from_fd(attr, NULL);
-	case BPF_LIRC_MODE2:
+	case BPF_PROG_TYPE_LIRC_MODE2:
 		return lirc_prog_detach(attr);
-	case BPF_FLOW_DISSECTOR:
+	case BPF_PROG_TYPE_FLOW_DISSECTOR:
 		return skb_flow_dissector_bpf_prog_detach(attr);
-	case BPF_CGROUP_SYSCTL:
-		ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
-		break;
-	case BPF_CGROUP_GETSOCKOPT:
-	case BPF_CGROUP_SETSOCKOPT:
-		ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
-		break;
+	case BPF_PROG_TYPE_CGROUP_DEVICE:
+	case BPF_PROG_TYPE_CGROUP_SKB:
+	case BPF_PROG_TYPE_CGROUP_SOCK:
+	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+	case BPF_PROG_TYPE_CGROUP_SYSCTL:
+	case BPF_PROG_TYPE_SOCK_OPS:
+		return cgroup_bpf_prog_detach(attr, ptype);
 	default:
 		return -EINVAL;
 	}
-
-	return cgroup_bpf_prog_detach(attr, ptype);
 }
 
 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
@@ -2734,7 +2732,7 @@ static int bpf_prog_query(const union bpf_attr *attr,
 	case BPF_CGROUP_SYSCTL:
 	case BPF_CGROUP_GETSOCKOPT:
 	case BPF_CGROUP_SETSOCKOPT:
-		break;
+		return cgroup_bpf_prog_query(attr, uattr);
 	case BPF_LIRC_MODE2:
 		return lirc_prog_query(attr, uattr);
 	case BPF_FLOW_DISSECTOR:
@@ -2742,8 +2740,6 @@ static int bpf_prog_query(const union bpf_attr *attr,
 	default:
 		return -EINVAL;
 	}
-
-	return cgroup_bpf_prog_query(attr, uattr);
 }
 
 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
@@ -3564,6 +3560,104 @@ err_put:
 	return err;
 }
 
+#define BPF_LINK_CREATE_LAST_FIELD link_create.flags
+static int link_create(union bpf_attr *attr)
+{
+	enum bpf_prog_type ptype;
+	struct bpf_prog *prog;
+	int ret;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (CHECK_ATTR(BPF_LINK_CREATE))
+		return -EINVAL;
+
+	ptype = attach_type_to_prog_type(attr->link_create.attach_type);
+	if (ptype == BPF_PROG_TYPE_UNSPEC)
+		return -EINVAL;
+
+	prog = bpf_prog_get_type(attr->link_create.prog_fd, ptype);
+	if (IS_ERR(prog))
+		return PTR_ERR(prog);
+
+	ret = bpf_prog_attach_check_attach_type(prog,
+						attr->link_create.attach_type);
+	if (ret)
+		goto err_out;
+
+	switch (ptype) {
+	case BPF_PROG_TYPE_CGROUP_SKB:
+	case BPF_PROG_TYPE_CGROUP_SOCK:
+	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+	case BPF_PROG_TYPE_SOCK_OPS:
+	case BPF_PROG_TYPE_CGROUP_DEVICE:
+	case BPF_PROG_TYPE_CGROUP_SYSCTL:
+	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+		ret = cgroup_bpf_link_attach(attr, prog);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+err_out:
+	if (ret < 0)
+		bpf_prog_put(prog);
+	return ret;
+}
+
+#define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
+
+static int link_update(union bpf_attr *attr)
+{
+	struct bpf_prog *old_prog = NULL, *new_prog;
+	struct bpf_link *link;
+	u32 flags;
+	int ret;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (CHECK_ATTR(BPF_LINK_UPDATE))
+		return -EINVAL;
+
+	flags = attr->link_update.flags;
+	if (flags & ~BPF_F_REPLACE)
+		return -EINVAL;
+
+	link = bpf_link_get_from_fd(attr->link_update.link_fd);
+	if (IS_ERR(link))
+		return PTR_ERR(link);
+
+	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
+	if (IS_ERR(new_prog))
+		return PTR_ERR(new_prog);
+
+	if (flags & BPF_F_REPLACE) {
+		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
+		if (IS_ERR(old_prog)) {
+			ret = PTR_ERR(old_prog);
+			old_prog = NULL;
+			goto out_put_progs;
+		}
+	}
+
+#ifdef CONFIG_CGROUP_BPF
+	if (link->ops == &bpf_cgroup_link_lops) {
+		ret = cgroup_bpf_replace(link, old_prog, new_prog);
+		goto out_put_progs;
+	}
+#endif
+	ret = -EINVAL;
+
+out_put_progs:
+	if (old_prog)
+		bpf_prog_put(old_prog);
+	if (ret)
+		bpf_prog_put(new_prog);
+	return ret;
+}
+
 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
 {
 	union bpf_attr attr;
@@ -3675,6 +3769,12 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
 	case BPF_MAP_DELETE_BATCH:
 		err = bpf_map_do_batch(&attr, uattr, BPF_MAP_DELETE_BATCH);
 		break;
+	case BPF_LINK_CREATE:
+		err = link_create(&attr);
+		break;
+	case BPF_LINK_UPDATE:
+		err = link_update(&attr);
+		break;
 	default:
 		err = -EINVAL;
 		break;