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

Daniel Borkmann says:

====================
pull-request: bpf 2018-07-28

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

The main changes are:

1) API fixes for libbpf's BTF mapping of map key/value types in order
   to make them compatible with iproute2's BPF_ANNOTATE_KV_PAIR()
   markings, from Martin.

2) Fix AF_XDP to not report POLLIN prematurely by using the non-cached
   consumer pointer of the RX queue, from Björn.

3) Fix __xdp_return() to check for NULL pointer after the rhashtable
   lookup that retrieves the allocator object, from Taehee.

4) Fix x86-32 JIT to adjust ebp register in prologue and epilogue
   by 4 bytes which got removed from overall stack usage, from Wang.

5) Fix bpf_skb_load_bytes_relative() length check to use actual
   packet length, from Daniel.

6) Fix uninitialized return code in libbpf bpf_perf_event_read_simple()
   handler, from Thomas.
====================

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

2 files changed, 14 insertions, 2 deletions

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 544e58f5f642..2aa55d030c77 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -378,7 +378,7 @@ static int array_map_check_btf(const struct bpf_map *map, const struct btf *btf,
 		return -EINVAL;
 
 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
-	if (!value_type || value_size > map->value_size)
+	if (!value_type || value_size != map->value_size)
 		return -EINVAL;
 
 	return 0;
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 9704934252b3..2590700237c1 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -1519,9 +1519,9 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env,
 {
 	bool is_union = BTF_INFO_KIND(t->info) == BTF_KIND_UNION;
 	const struct btf_member *member;
+	u32 meta_needed, last_offset;
 	struct btf *btf = env->btf;
 	u32 struct_size = t->size;
-	u32 meta_needed;
 	u16 i;
 
 	meta_needed = btf_type_vlen(t) * sizeof(*member);
@@ -1534,6 +1534,7 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env,
 
 	btf_verifier_log_type(env, t, NULL);
 
+	last_offset = 0;
 	for_each_member(i, t, member) {
 		if (!btf_name_offset_valid(btf, member->name_off)) {
 			btf_verifier_log_member(env, t, member,
@@ -1555,6 +1556,16 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env,
 			return -EINVAL;
 		}
 
+		/*
+		 * ">" instead of ">=" because the last member could be
+		 * "char a[0];"
+		 */
+		if (last_offset > member->offset) {
+			btf_verifier_log_member(env, t, member,
+						"Invalid member bits_offset");
+			return -EINVAL;
+		}
+
 		if (BITS_ROUNDUP_BYTES(member->offset) > struct_size) {
 			btf_verifier_log_member(env, t, member,
 						"Memmber bits_offset exceeds its struct size");
@@ -1562,6 +1573,7 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env,
 		}
 
 		btf_verifier_log_member(env, t, member, NULL);
+		last_offset = member->offset;
 	}
 
 	return meta_needed;