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

Alexei Starovoitov says:

====================
pull-request: bpf 2020-07-09

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

We've added 4 non-merge commits during the last 1 day(s) which contain
a total of 4 files changed, 26 insertions(+), 15 deletions(-).

The main changes are:

1) fix crash in libbpf on 32-bit archs, from Jakub and Andrii.

2) fix crash when l2tp and bpf_sk_reuseport conflict, from Martin.
====================

Signed-off-by: David S. Miller <[email protected]>

Author: davem330

include/net/sock.h

@@ -533,7 +533,8 @@ enum sk_pacing {
  * be copied.
  */
 #define SK_USER_DATA_NOCOPY	1UL
-#define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY)
+#define SK_USER_DATA_BPF	2UL	/* Managed by BPF */
+#define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF)
 
 /**
  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied

kernel/bpf/reuseport_array.c

@@ -20,11 +20,14 @@ static struct reuseport_array *reuseport_array(struct bpf_map *map)
 /* The caller must hold the reuseport_lock */
 void bpf_sk_reuseport_detach(struct sock *sk)
 {
-	struct sock __rcu **socks;
+	uintptr_t sk_user_data;
 
 	write_lock_bh(&sk->sk_callback_lock);
-	socks = sk->sk_user_data;
-	if (socks) {
+	sk_user_data = (uintptr_t)sk->sk_user_data;
+	if (sk_user_data & SK_USER_DATA_BPF) {
+		struct sock __rcu **socks;
+
+		socks = (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
 		WRITE_ONCE(sk->sk_user_data, NULL);
 		/*
 		 * Do not move this NULL assignment outside of
@@ -252,6 +255,7 @@ int bpf_fd_reuseport_array_update_elem(struct bpf_map *map, void *key,
 	struct sock *free_osk = NULL, *osk, *nsk;
 	struct sock_reuseport *reuse;
 	u32 index = *(u32 *)key;
+	uintptr_t sk_user_data;
 	struct socket *socket;
 	int err, fd;
 
@@ -305,7 +309,9 @@ int bpf_fd_reuseport_array_update_elem(struct bpf_map *map, void *key,
 	if (err)
 		goto put_file_unlock;
 
-	WRITE_ONCE(nsk->sk_user_data, &array->ptrs[index]);
+	sk_user_data = (uintptr_t)&array->ptrs[index] | SK_USER_DATA_NOCOPY |
+		SK_USER_DATA_BPF;
+	WRITE_ONCE(nsk->sk_user_data, (void *)sk_user_data);
 	rcu_assign_pointer(array->ptrs[index], nsk);
 	free_osk = osk;
 	err = 0;

tools/lib/bpf/hashmap.h

@@ -11,14 +11,18 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <limits.h>
-#ifndef __WORDSIZE
-#define __WORDSIZE (__SIZEOF_LONG__ * 8)
-#endif
 
 static inline size_t hash_bits(size_t h, int bits)
 {
 	/* shuffle bits and return requested number of upper bits */
-	return (h * 11400714819323198485llu) >> (__WORDSIZE - bits);
+#if (__SIZEOF_SIZE_T__ == __SIZEOF_LONG_LONG__)
+	/* LP64 case */
+	return (h * 11400714819323198485llu) >> (__SIZEOF_LONG_LONG__ * 8 - bits);
+#elif (__SIZEOF_SIZE_T__ <= __SIZEOF_LONG__)
+	return (h * 2654435769lu) >> (__SIZEOF_LONG__ * 8 - bits);
+#else
+#	error "Unsupported size_t size"
+#endif
 }
 
 typedef size_t (*hashmap_hash_fn)(const void *key, void *ctx);

tools/testing/selftests/bpf/test_maps.c

@@ -789,19 +789,19 @@ static void test_sockmap(unsigned int tasks, void *data)
 	}
 
 	err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_PARSER);
-	if (err) {
+	if (!err) {
 		printf("Failed empty parser prog detach\n");
 		goto out_sockmap;
 	}
 
 	err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_VERDICT);
-	if (err) {
+	if (!err) {
 		printf("Failed empty verdict prog detach\n");
 		goto out_sockmap;
 	}
 
 	err = bpf_prog_detach(fd, BPF_SK_MSG_VERDICT);
-	if (err) {
+	if (!err) {
 		printf("Failed empty msg verdict prog detach\n");
 		goto out_sockmap;
 	}
@@ -1090,19 +1090,19 @@ static void test_sockmap(unsigned int tasks, void *data)
 		assert(status == 0);
 	}
 
-	err = bpf_prog_detach(map_fd_rx, __MAX_BPF_ATTACH_TYPE);
+	err = bpf_prog_detach2(parse_prog, map_fd_rx, __MAX_BPF_ATTACH_TYPE);
 	if (!err) {
 		printf("Detached an invalid prog type.\n");
 		goto out_sockmap;
 	}
 
-	err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_PARSER);
+	err = bpf_prog_detach2(parse_prog, map_fd_rx, BPF_SK_SKB_STREAM_PARSER);
 	if (err) {
 		printf("Failed parser prog detach\n");
 		goto out_sockmap;
 	}
 
-	err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_VERDICT);
+	err = bpf_prog_detach2(verdict_prog, map_fd_rx, BPF_SK_SKB_STREAM_VERDICT);
 	if (err) {
 		printf("Failed parser prog detach\n");
 		goto out_sockmap;