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

Daniel Borkmann says:

====================
pull-request: bpf 2020-06-30

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

We've added 28 non-merge commits during the last 9 day(s) which contain
a total of 35 files changed, 486 insertions(+), 232 deletions(-).

The main changes are:

1) Fix an incorrect verifier branch elimination for PTR_TO_BTF_ID pointer
   types, from Yonghong Song.

2) Fix UAPI for sockmap and flow_dissector progs that were ignoring various
   arguments passed to BPF_PROG_{ATTACH,DETACH}, from Lorenz Bauer & Jakub Sitnicki.

3) Fix broken AF_XDP DMA hacks that are poking into dma-direct and swiotlb
   internals and integrate it properly into DMA core, from Christoph Hellwig.

4) Fix RCU splat from recent changes to avoid skipping ingress policy when
   kTLS is enabled, from John Fastabend.

5) Fix BPF ringbuf map to enforce size to be the power of 2 in order for its
   position masking to work, from Andrii Nakryiko.

6) Fix regression from CAP_BPF work to re-allow CAP_SYS_ADMIN for loading
   of network programs, from Maciej Żenczykowski.

7) Fix libbpf section name prefix for devmap progs, from Jesper Dangaard Brouer.

8) Fix formatting in UAPI documentation for BPF helpers, from Quentin Monnet.
====================

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

12 files changed, 139 insertions, 38 deletions

diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 974a71342aea..8bd33050b7bb 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -3171,13 +3171,12 @@ union bpf_attr {
  * int bpf_ringbuf_output(void *ringbuf, void *data, u64 size, u64 flags)
  * 	Description
  * 		Copy *size* bytes from *data* into a ring buffer *ringbuf*.
- * 		If BPF_RB_NO_WAKEUP is specified in *flags*, no notification of
- * 		new data availability is sent.
- * 		IF BPF_RB_FORCE_WAKEUP is specified in *flags*, notification of
- * 		new data availability is sent unconditionally.
+ * 		If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
+ * 		of new data availability is sent.
+ * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
+ * 		of new data availability is sent unconditionally.
  * 	Return
- * 		0, on success;
- * 		< 0, on error.
+ * 		0 on success, or a negative error in case of failure.
  *
  * void *bpf_ringbuf_reserve(void *ringbuf, u64 size, u64 flags)
  * 	Description
@@ -3189,20 +3188,20 @@ union bpf_attr {
  * void bpf_ringbuf_submit(void *data, u64 flags)
  * 	Description
  * 		Submit reserved ring buffer sample, pointed to by *data*.
- * 		If BPF_RB_NO_WAKEUP is specified in *flags*, no notification of
- * 		new data availability is sent.
- * 		IF BPF_RB_FORCE_WAKEUP is specified in *flags*, notification of
- * 		new data availability is sent unconditionally.
+ * 		If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
+ * 		of new data availability is sent.
+ * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
+ * 		of new data availability is sent unconditionally.
  * 	Return
  * 		Nothing. Always succeeds.
  *
  * void bpf_ringbuf_discard(void *data, u64 flags)
  * 	Description
  * 		Discard reserved ring buffer sample, pointed to by *data*.
- * 		If BPF_RB_NO_WAKEUP is specified in *flags*, no notification of
- * 		new data availability is sent.
- * 		IF BPF_RB_FORCE_WAKEUP is specified in *flags*, notification of
- * 		new data availability is sent unconditionally.
+ * 		If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification
+ * 		of new data availability is sent.
+ * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
+ * 		of new data availability is sent unconditionally.
  * 	Return
  * 		Nothing. Always succeeds.
  *
@@ -3210,16 +3209,18 @@ union bpf_attr {
  *	Description
  *		Query various characteristics of provided ring buffer. What
  *		exactly is queries is determined by *flags*:
- *		  - BPF_RB_AVAIL_DATA - amount of data not yet consumed;
- *		  - BPF_RB_RING_SIZE - the size of ring buffer;
- *		  - BPF_RB_CONS_POS - consumer position (can wrap around);
- *		  - BPF_RB_PROD_POS - producer(s) position (can wrap around);
- *		Data returned is just a momentary snapshots of actual values
+ *
+ *		* **BPF_RB_AVAIL_DATA**: Amount of data not yet consumed.
+ *		* **BPF_RB_RING_SIZE**: The size of ring buffer.
+ *		* **BPF_RB_CONS_POS**: Consumer position (can wrap around).
+ *		* **BPF_RB_PROD_POS**: Producer(s) position (can wrap around).
+ *
+ *		Data returned is just a momentary snapshot of actual values
  *		and could be inaccurate, so this facility should be used to
  *		power heuristics and for reporting, not to make 100% correct
  *		calculation.
  *	Return
- *		Requested value, or 0, if flags are not recognized.
+ *		Requested value, or 0, if *flags* are not recognized.
  *
  * int bpf_csum_level(struct sk_buff *skb, u64 level)
  * 	Description
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 1b6015b21ba8..dbef24ebcfcb 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -233,6 +233,8 @@ LIBBPF_API int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf,
 LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf,
 				 __u32 *buf_len, __u32 *prog_id, __u32 *fd_type,
 				 __u64 *probe_offset, __u64 *probe_addr);
+
+enum bpf_stats_type; /* defined in up-to-date linux/bpf.h */
 LIBBPF_API int bpf_enable_stats(enum bpf_stats_type type);
 
 #ifdef __cplusplus
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 477c679ed945..11e4725b8b1c 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -4818,7 +4818,13 @@ bpf_core_reloc_fields(struct bpf_object *obj, const char *targ_btf_path)
 			err = -EINVAL;
 			goto out;
 		}
-		prog = bpf_object__find_program_by_title(obj, sec_name);
+		prog = NULL;
+		for (i = 0; i < obj->nr_programs; i++) {
+			if (!strcmp(obj->programs[i].section_name, sec_name)) {
+				prog = &obj->programs[i];
+				break;
+			}
+		}
 		if (!prog) {
 			pr_warn("failed to find program '%s' for CO-RE offset relocation\n",
 				sec_name);
@@ -6653,7 +6659,7 @@ static const struct bpf_sec_def section_defs[] = {
 		.expected_attach_type = BPF_TRACE_ITER,
 		.is_attach_btf = true,
 		.attach_fn = attach_iter),
-	BPF_EAPROG_SEC("xdp_devmap",		BPF_PROG_TYPE_XDP,
+	BPF_EAPROG_SEC("xdp_devmap/",		BPF_PROG_TYPE_XDP,
 						BPF_XDP_DEVMAP),
 	BPF_PROG_SEC("xdp",			BPF_PROG_TYPE_XDP),
 	BPF_PROG_SEC("perf_event",		BPF_PROG_TYPE_PERF_EVENT),
diff --git a/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c b/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c
index 83493bd5745c..109d0345a2be 100644
--- a/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c
+++ b/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c
@@ -36,7 +36,7 @@ void test_fentry_fexit(void)
 	fentry_res = (__u64 *)fentry_skel->bss;
 	fexit_res = (__u64 *)fexit_skel->bss;
 	printf("%lld\n", fentry_skel->bss->test1_result);
-	for (i = 0; i < 6; i++) {
+	for (i = 0; i < 8; i++) {
 		CHECK(fentry_res[i] != 1, "result",
 		      "fentry_test%d failed err %lld\n", i + 1, fentry_res[i]);
 		CHECK(fexit_res[i] != 1, "result",
diff --git a/tools/testing/selftests/bpf/prog_tests/flow_dissector.c b/tools/testing/selftests/bpf/prog_tests/flow_dissector.c
index ea14e3ece812..f11f187990e9 100644
--- a/tools/testing/selftests/bpf/prog_tests/flow_dissector.c
+++ b/tools/testing/selftests/bpf/prog_tests/flow_dissector.c
@@ -527,8 +527,8 @@ static void test_skb_less_prog_attach(struct bpf_flow *skel, int tap_fd)
 
 	run_tests_skb_less(tap_fd, skel->maps.last_dissection);
 
-	err = bpf_prog_detach(prog_fd, BPF_FLOW_DISSECTOR);
-	CHECK(err, "bpf_prog_detach", "err %d errno %d\n", err, errno);
+	err = bpf_prog_detach2(prog_fd, 0, BPF_FLOW_DISSECTOR);
+	CHECK(err, "bpf_prog_detach2", "err %d errno %d\n", err, errno);
 }
 
 static void test_skb_less_link_create(struct bpf_flow *skel, int tap_fd)
diff --git a/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c b/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c
index 15cb554a66d8..172c586b6996 100644
--- a/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c
+++ b/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c
@@ -1,9 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Test that the flow_dissector program can be updated with a single
- * syscall by attaching a new program that replaces the existing one.
- *
- * Corner case - the same program cannot be attached twice.
+ * Tests for attaching, detaching, and replacing flow_dissector BPF program.
  */
 
 #define _GNU_SOURCE
@@ -116,7 +113,7 @@ static void test_prog_attach_prog_attach(int netns, int prog1, int prog2)
 	CHECK_FAIL(query_attached_prog_id(netns) != query_prog_id(prog2));
 
 out_detach:
-	err = bpf_prog_detach(0, BPF_FLOW_DISSECTOR);
+	err = bpf_prog_detach2(prog2, 0, BPF_FLOW_DISSECTOR);
 	if (CHECK_FAIL(err))
 		perror("bpf_prog_detach");
 	CHECK_FAIL(prog_is_attached(netns));
@@ -152,7 +149,7 @@ static void test_prog_attach_link_create(int netns, int prog1, int prog2)
 	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
 	int err, link;
 
-	err = bpf_prog_attach(prog1, -1, BPF_FLOW_DISSECTOR, 0);
+	err = bpf_prog_attach(prog1, 0, BPF_FLOW_DISSECTOR, 0);
 	if (CHECK_FAIL(err)) {
 		perror("bpf_prog_attach(prog1)");
 		return;
@@ -168,7 +165,7 @@ static void test_prog_attach_link_create(int netns, int prog1, int prog2)
 		close(link);
 	CHECK_FAIL(query_attached_prog_id(netns) != query_prog_id(prog1));
 
-	err = bpf_prog_detach(-1, BPF_FLOW_DISSECTOR);
+	err = bpf_prog_detach2(prog1, 0, BPF_FLOW_DISSECTOR);
 	if (CHECK_FAIL(err))
 		perror("bpf_prog_detach");
 	CHECK_FAIL(prog_is_attached(netns));
@@ -188,7 +185,7 @@ static void test_link_create_prog_attach(int netns, int prog1, int prog2)
 
 	/* Expect failure attaching prog when link exists */
 	errno = 0;
-	err = bpf_prog_attach(prog2, -1, BPF_FLOW_DISSECTOR, 0);
+	err = bpf_prog_attach(prog2, 0, BPF_FLOW_DISSECTOR, 0);
 	if (CHECK_FAIL(!err || errno != EEXIST))
 		perror("bpf_prog_attach(prog2) expected EEXIST");
 	CHECK_FAIL(query_attached_prog_id(netns) != query_prog_id(prog1));
@@ -211,7 +208,7 @@ static void test_link_create_prog_detach(int netns, int prog1, int prog2)
 
 	/* Expect failure detaching prog when link exists */
 	errno = 0;
-	err = bpf_prog_detach(-1, BPF_FLOW_DISSECTOR);
+	err = bpf_prog_detach2(prog1, 0, BPF_FLOW_DISSECTOR);
 	if (CHECK_FAIL(!err || errno != EINVAL))
 		perror("bpf_prog_detach expected EINVAL");
 	CHECK_FAIL(query_attached_prog_id(netns) != query_prog_id(prog1));
@@ -231,7 +228,7 @@ static void test_prog_attach_detach_query(int netns, int prog1, int prog2)
 	}
 	CHECK_FAIL(query_attached_prog_id(netns) != query_prog_id(prog1));
 
-	err = bpf_prog_detach(0, BPF_FLOW_DISSECTOR);
+	err = bpf_prog_detach2(prog1, 0, BPF_FLOW_DISSECTOR);
 	if (CHECK_FAIL(err)) {
 		perror("bpf_prog_detach");
 		return;
@@ -308,6 +305,31 @@ static void test_link_update_replace_old_prog(int netns, int prog1, int prog2)
 	CHECK_FAIL(prog_is_attached(netns));
 }
 
+static void test_link_update_same_prog(int netns, int prog1, int prog2)
+{
+	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, create_opts);
+	DECLARE_LIBBPF_OPTS(bpf_link_update_opts, update_opts);
+	int err, link;
+
+	link = bpf_link_create(prog1, netns, BPF_FLOW_DISSECTOR, &create_opts);
+	if (CHECK_FAIL(link < 0)) {
+		perror("bpf_link_create(prog1)");
+		return;
+	}
+	CHECK_FAIL(query_attached_prog_id(netns) != query_prog_id(prog1));
+
+	/* Expect success updating the prog with the same one */
+	update_opts.flags = 0;
+	update_opts.old_prog_fd = 0;
+	err = bpf_link_update(link, prog1, &update_opts);
+	if (CHECK_FAIL(err))
+		perror("bpf_link_update");
+	CHECK_FAIL(query_attached_prog_id(netns) != query_prog_id(prog1));
+
+	close(link);
+	CHECK_FAIL(prog_is_attached(netns));
+}
+
 static void test_link_update_invalid_opts(int netns, int prog1, int prog2)
 {
 	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, create_opts);
@@ -571,6 +593,8 @@ static void run_tests(int netns)
 		  test_link_update_no_old_prog },
 		{ "link update with replace old prog",
 		  test_link_update_replace_old_prog },
+		{ "link update with same prog",
+		  test_link_update_same_prog },
 		{ "link update invalid opts",
 		  test_link_update_invalid_opts },
 		{ "link update invalid prog",
diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c b/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c
index e7b8753eac0b..75ecf956a2df 100644
--- a/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c
@@ -25,7 +25,7 @@ struct bpf_iter__netlink {
 	struct netlink_sock *sk;
 } __attribute__((preserve_access_index));
 
-static inline struct inode *SOCK_INODE(struct socket *socket)
+static __attribute__((noinline)) struct inode *SOCK_INODE(struct socket *socket)
 {
 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
 }
diff --git a/tools/testing/selftests/bpf/progs/fentry_test.c b/tools/testing/selftests/bpf/progs/fentry_test.c
index 9365b686f84b..5f645fdaba6f 100644
--- a/tools/testing/selftests/bpf/progs/fentry_test.c
+++ b/tools/testing/selftests/bpf/progs/fentry_test.c
@@ -55,3 +55,25 @@ int BPF_PROG(test6, __u64 a, void *b, short c, int d, void * e, __u64 f)
 		e == (void *)20 && f == 21;
 	return 0;
 }
+
+struct bpf_fentry_test_t {
+	struct bpf_fentry_test_t *a;
+};
+
+__u64 test7_result = 0;
+SEC("fentry/bpf_fentry_test7")
+int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
+{
+	if (arg == 0)
+		test7_result = 1;
+	return 0;
+}
+
+__u64 test8_result = 0;
+SEC("fentry/bpf_fentry_test8")
+int BPF_PROG(test8, struct bpf_fentry_test_t *arg)
+{
+	if (arg->a == 0)
+		test8_result = 1;
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/fexit_test.c b/tools/testing/selftests/bpf/progs/fexit_test.c
index bd1e17d8024c..0952affb22a6 100644
--- a/tools/testing/selftests/bpf/progs/fexit_test.c
+++ b/tools/testing/selftests/bpf/progs/fexit_test.c
@@ -56,3 +56,25 @@ int BPF_PROG(test6, __u64 a, void *b, short c, int d, void *e, __u64 f, int ret)
 		e == (void *)20 && f == 21 && ret == 111;
 	return 0;
 }
+
+struct bpf_fentry_test_t {
+	struct bpf_fentry_test *a;
+};
+
+__u64 test7_result = 0;
+SEC("fexit/bpf_fentry_test7")
+int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
+{
+	if (arg == 0)
+		test7_result = 1;
+	return 0;
+}
+
+__u64 test8_result = 0;
+SEC("fexit/bpf_fentry_test8")
+int BPF_PROG(test8, struct bpf_fentry_test_t *arg)
+{
+	if (arg->a == 0)
+		test8_result = 1;
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/test_sockmap_kern.h b/tools/testing/selftests/bpf/progs/test_sockmap_kern.h
index 057036ca1111..3dca4c2e2418 100644
--- a/tools/testing/selftests/bpf/progs/test_sockmap_kern.h
+++ b/tools/testing/selftests/bpf/progs/test_sockmap_kern.h
@@ -79,7 +79,7 @@ struct {
 
 struct {
 	__uint(type, BPF_MAP_TYPE_ARRAY);
-	__uint(max_entries, 2);
+	__uint(max_entries, 3);
 	__type(key, int);
 	__type(value, int);
 } sock_skb_opts SEC(".maps");
@@ -94,6 +94,12 @@ struct {
 SEC("sk_skb1")
 int bpf_prog1(struct __sk_buff *skb)
 {
+	int *f, two = 2;
+
+	f = bpf_map_lookup_elem(&sock_skb_opts, &two);
+	if (f && *f) {
+		return *f;
+	}
 	return skb->len;
 }
 
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c b/tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c
index 330811260123..0ac086497722 100644
--- a/tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c
+++ b/tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c
@@ -27,7 +27,7 @@ int xdp_dummy_prog(struct xdp_md *ctx)
 /* valid program on DEVMAP entry via SEC name;
  * has access to egress and ingress ifindex
  */
-SEC("xdp_devmap")
+SEC("xdp_devmap/map_prog")
 int xdp_dummy_dm(struct xdp_md *ctx)
 {
 	char fmt[] = "devmap redirect: dev %u -> dev %u len %u\n";
diff --git a/tools/testing/selftests/bpf/test_sockmap.c b/tools/testing/selftests/bpf/test_sockmap.c
index 37695fc8096a..78789b27e573 100644
--- a/tools/testing/selftests/bpf/test_sockmap.c
+++ b/tools/testing/selftests/bpf/test_sockmap.c
@@ -85,6 +85,7 @@ int txmsg_ktls_skb_drop;
 int txmsg_ktls_skb_redir;
 int ktls;
 int peek_flag;
+int skb_use_parser;
 
 static const struct option long_options[] = {
 	{"help",	no_argument,		NULL, 'h' },
@@ -174,6 +175,7 @@ static void test_reset(void)
 	txmsg_apply = txmsg_cork = 0;
 	txmsg_ingress = txmsg_redir_skb = 0;
 	txmsg_ktls_skb = txmsg_ktls_skb_drop = txmsg_ktls_skb_redir = 0;
+	skb_use_parser = 0;
 }
 
 static int test_start_subtest(const struct _test *t, struct sockmap_options *o)
@@ -1211,6 +1213,11 @@ run:
 		}
 	}
 
+	if (skb_use_parser) {
+		i = 2;
+		err = bpf_map_update_elem(map_fd[7], &i, &skb_use_parser, BPF_ANY);
+	}
+
 	if (txmsg_drop)
 		options->drop_expected = true;
 
@@ -1650,6 +1657,16 @@ static void test_txmsg_cork(int cgrp, struct sockmap_options *opt)
 	test_send(opt, cgrp);
 }
 
+static void test_txmsg_ingress_parser(int cgrp, struct sockmap_options *opt)
+{
+	txmsg_pass = 1;
+	skb_use_parser = 512;
+	opt->iov_length = 256;
+	opt->iov_count = 1;
+	opt->rate = 2;
+	test_exec(cgrp, opt);
+}
+
 char *map_names[] = {
 	"sock_map",
 	"sock_map_txmsg",
@@ -1748,6 +1765,7 @@ struct _test test[] = {
 	{"txmsg test pull-data", test_txmsg_pull},
 	{"txmsg test pop-data", test_txmsg_pop},
 	{"txmsg test push/pop data", test_txmsg_push_pop},
+	{"txmsg text ingress parser", test_txmsg_ingress_parser},
 };
 
 static int check_whitelist(struct _test *t, struct sockmap_options *opt)