Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2019-04-12

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Improve BPF verifier scalability for large programs through two
   optimizations: i) remove verifier states that are not useful in pruning,
   ii) stop walking parentage chain once first LIVE_READ is seen. Combined
   gives approx 20x speedup. Increase limits for accepting large programs
   under root, and add various stress tests, from Alexei.

2) Implement global data support in BPF. This enables static global variables
   for .data, .rodata and .bss sections to be properly handled which allows
   for more natural program development. This also opens up the possibility
   to optimize program workflow by compiling ELFs only once and later only
   rewriting section data before reload, from Daniel and with test cases and
   libbpf refactoring from Joe.

3) Add config option to generate BTF type info for vmlinux as part of the
   kernel build process. DWARF debug info is converted via pahole to BTF.
   Latter relies on libbpf and makes use of BTF deduplication algorithm which
   results in 100x savings compared to DWARF data. Resulting .BTF section is
   typically about 2MB in size, from Andrii.

4) Add BPF verifier support for stack access with variable offset from
   helpers and add various test cases along with it, from Andrey.

5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header
   so that L2 encapsulation can be used for tc tunnels, from Alan.

6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that
   users can define a subset of allowed __sk_buff fields that get fed into
   the test program, from Stanislav.

7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up
   various UBSAN warnings in bpftool, from Yonghong.

8) Generate a pkg-config file for libbpf, from Luca.

9) Dump program's BTF id in bpftool, from Prashant.

10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP
    program, from Magnus.

11) kallsyms related fixes for the case when symbols are not present in
    BPF selftests and samples, from Daniel
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 115 insertions, 29 deletions

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index afca36f53c49..d995eedfdd16 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -166,13 +166,25 @@ void bpf_map_area_free(void *area)
 	kvfree(area);
 }
 
+static u32 bpf_map_flags_retain_permanent(u32 flags)
+{
+	/* Some map creation flags are not tied to the map object but
+	 * rather to the map fd instead, so they have no meaning upon
+	 * map object inspection since multiple file descriptors with
+	 * different (access) properties can exist here. Thus, given
+	 * this has zero meaning for the map itself, lets clear these
+	 * from here.
+	 */
+	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
+}
+
 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
 {
 	map->map_type = attr->map_type;
 	map->key_size = attr->key_size;
 	map->value_size = attr->value_size;
 	map->max_entries = attr->max_entries;
-	map->map_flags = attr->map_flags;
+	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
 	map->numa_node = bpf_map_attr_numa_node(attr);
 }
 
@@ -343,6 +355,18 @@ static int bpf_map_release(struct inode *inode, struct file *filp)
 	return 0;
 }
 
+static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
+{
+	fmode_t mode = f.file->f_mode;
+
+	/* Our file permissions may have been overridden by global
+	 * map permissions facing syscall side.
+	 */
+	if (READ_ONCE(map->frozen))
+		mode &= ~FMODE_CAN_WRITE;
+	return mode;
+}
+
 #ifdef CONFIG_PROC_FS
 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 {
@@ -364,14 +388,16 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 		   "max_entries:\t%u\n"
 		   "map_flags:\t%#x\n"
 		   "memlock:\t%llu\n"
-		   "map_id:\t%u\n",
+		   "map_id:\t%u\n"
+		   "frozen:\t%u\n",
 		   map->map_type,
 		   map->key_size,
 		   map->value_size,
 		   map->max_entries,
 		   map->map_flags,
 		   map->pages * 1ULL << PAGE_SHIFT,
-		   map->id);
+		   map->id,
+		   READ_ONCE(map->frozen));
 
 	if (owner_prog_type) {
 		seq_printf(m, "owner_prog_type:\t%u\n",
@@ -448,10 +474,10 @@ static int bpf_obj_name_cpy(char *dst, const char *src)
 	const char *end = src + BPF_OBJ_NAME_LEN;
 
 	memset(dst, 0, BPF_OBJ_NAME_LEN);
-
-	/* Copy all isalnum() and '_' char */
+	/* Copy all isalnum(), '_' and '.' chars. */
 	while (src < end && *src) {
-		if (!isalnum(*src) && *src != '_')
+		if (!isalnum(*src) &&
+		    *src != '_' && *src != '.')
 			return -EINVAL;
 		*dst++ = *src++;
 	}
@@ -478,9 +504,16 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
 	u32 key_size, value_size;
 	int ret = 0;
 
-	key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
-	if (!key_type || key_size != map->key_size)
-		return -EINVAL;
+	/* Some maps allow key to be unspecified. */
+	if (btf_key_id) {
+		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
+		if (!key_type || key_size != map->key_size)
+			return -EINVAL;
+	} else {
+		key_type = btf_type_by_id(btf, 0);
+		if (!map->ops->map_check_btf)
+			return -EINVAL;
+	}
 
 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
 	if (!value_type || value_size != map->value_size)
@@ -489,6 +522,8 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
 	map->spin_lock_off = btf_find_spin_lock(btf, value_type);
 
 	if (map_value_has_spin_lock(map)) {
+		if (map->map_flags & BPF_F_RDONLY_PROG)
+			return -EACCES;
 		if (map->map_type != BPF_MAP_TYPE_HASH &&
 		    map->map_type != BPF_MAP_TYPE_ARRAY &&
 		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE)
@@ -545,7 +580,7 @@ static int map_create(union bpf_attr *attr)
 	if (attr->btf_key_type_id || attr->btf_value_type_id) {
 		struct btf *btf;
 
-		if (!attr->btf_key_type_id || !attr->btf_value_type_id) {
+		if (!attr->btf_value_type_id) {
 			err = -EINVAL;
 			goto free_map_nouncharge;
 		}
@@ -713,8 +748,7 @@ static int map_lookup_elem(union bpf_attr *attr)
 	map = __bpf_map_get(f);
 	if (IS_ERR(map))
 		return PTR_ERR(map);
-
-	if (!(f.file->f_mode & FMODE_CAN_READ)) {
+	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
 		err = -EPERM;
 		goto err_put;
 	}
@@ -843,8 +877,7 @@ static int map_update_elem(union bpf_attr *attr)
 	map = __bpf_map_get(f);
 	if (IS_ERR(map))
 		return PTR_ERR(map);
-
-	if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
+	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
 		err = -EPERM;
 		goto err_put;
 	}
@@ -955,8 +988,7 @@ static int map_delete_elem(union bpf_attr *attr)
 	map = __bpf_map_get(f);
 	if (IS_ERR(map))
 		return PTR_ERR(map);
-
-	if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
+	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
 		err = -EPERM;
 		goto err_put;
 	}
@@ -1007,8 +1039,7 @@ static int map_get_next_key(union bpf_attr *attr)
 	map = __bpf_map_get(f);
 	if (IS_ERR(map))
 		return PTR_ERR(map);
-
-	if (!(f.file->f_mode & FMODE_CAN_READ)) {
+	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
 		err = -EPERM;
 		goto err_put;
 	}
@@ -1075,8 +1106,7 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr)
 	map = __bpf_map_get(f);
 	if (IS_ERR(map))
 		return PTR_ERR(map);
-
-	if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
+	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
 		err = -EPERM;
 		goto err_put;
 	}
@@ -1118,6 +1148,36 @@ err_put:
 	return err;
 }
 
+#define BPF_MAP_FREEZE_LAST_FIELD map_fd
+
+static int map_freeze(const union bpf_attr *attr)
+{
+	int err = 0, ufd = attr->map_fd;
+	struct bpf_map *map;
+	struct fd f;
+
+	if (CHECK_ATTR(BPF_MAP_FREEZE))
+		return -EINVAL;
+
+	f = fdget(ufd);
+	map = __bpf_map_get(f);
+	if (IS_ERR(map))
+		return PTR_ERR(map);
+	if (READ_ONCE(map->frozen)) {
+		err = -EBUSY;
+		goto err_put;
+	}
+	if (!capable(CAP_SYS_ADMIN)) {
+		err = -EPERM;
+		goto err_put;
+	}
+
+	WRITE_ONCE(map->frozen, true);
+err_put:
+	fdput(f);
+	return err;
+}
+
 static const struct bpf_prog_ops * const bpf_prog_types[] = {
 #define BPF_PROG_TYPE(_id, _name) \
 	[_id] = & _name ## _prog_ops,
@@ -1557,7 +1617,8 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
 	is_gpl = license_is_gpl_compatible(license);
 
-	if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS)
+	if (attr->insn_cnt == 0 ||
+	    attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
 		return -E2BIG;
 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
@@ -1948,7 +2009,7 @@ static int bpf_prog_query(const union bpf_attr *attr,
 	return cgroup_bpf_prog_query(attr, uattr);
 }
 
-#define BPF_PROG_TEST_RUN_LAST_FIELD test.duration
+#define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
 
 static int bpf_prog_test_run(const union bpf_attr *attr,
 			     union bpf_attr __user *uattr)
@@ -1961,6 +2022,14 @@ static int bpf_prog_test_run(const union bpf_attr *attr,
 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
 		return -EINVAL;
 
+	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
+	    (!attr->test.ctx_size_in && attr->test.ctx_in))
+		return -EINVAL;
+
+	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
+	    (!attr->test.ctx_size_out && attr->test.ctx_out))
+		return -EINVAL;
+
 	prog = bpf_prog_get(attr->test.prog_fd);
 	if (IS_ERR(prog))
 		return PTR_ERR(prog);
@@ -2071,13 +2140,26 @@ static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
 }
 
 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
-					      unsigned long addr)
+					      unsigned long addr, u32 *off,
+					      u32 *type)
 {
+	const struct bpf_map *map;
 	int i;
 
-	for (i = 0; i < prog->aux->used_map_cnt; i++)
-		if (prog->aux->used_maps[i] == (void *)addr)
-			return prog->aux->used_maps[i];
+	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
+		map = prog->aux->used_maps[i];
+		if (map == (void *)addr) {
+			*type = BPF_PSEUDO_MAP_FD;
+			return map;
+		}
+		if (!map->ops->map_direct_value_meta)
+			continue;
+		if (!map->ops->map_direct_value_meta(map, addr, off)) {
+			*type = BPF_PSEUDO_MAP_VALUE;
+			return map;
+		}
+	}
+
 	return NULL;
 }
 
@@ -2085,6 +2167,7 @@ static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
 {
 	const struct bpf_map *map;
 	struct bpf_insn *insns;
+	u32 off, type;
 	u64 imm;
 	int i;
 
@@ -2112,11 +2195,11 @@ static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
 			continue;
 
 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
-		map = bpf_map_from_imm(prog, imm);
+		map = bpf_map_from_imm(prog, imm, &off, &type);
 		if (map) {
-			insns[i].src_reg = BPF_PSEUDO_MAP_FD;
+			insns[i].src_reg = type;
 			insns[i].imm = map->id;
-			insns[i + 1].imm = 0;
+			insns[i + 1].imm = off;
 			continue;
 		}
 	}
@@ -2706,6 +2789,9 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
 	case BPF_MAP_GET_NEXT_KEY:
 		err = map_get_next_key(&attr);
 		break;
+	case BPF_MAP_FREEZE:
+		err = map_freeze(&attr);
+		break;
 	case BPF_PROG_LOAD:
 		err = bpf_prog_load(&attr, uattr);
 		break;