Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Martin KaFai Lau says:

====================
pull-request: bpf-next 2023-08-09

We've added 19 non-merge commits during the last 6 day(s) which contain
a total of 25 files changed, 369 insertions(+), 141 deletions(-).

The main changes are:

1) Fix array-index-out-of-bounds access when detaching from an
   already empty mprog entry from Daniel Borkmann.

2) Adjust bpf selftest because of a recent llvm change
   related to the cpu-v4 ISA from Eduard Zingerman.

3) Add uprobe support for the bpf_get_func_ip helper from Jiri Olsa.

4) Fix a KASAN splat due to the kernel incorrectly accepted
   an invalid program using the recent cpu-v4 instruction from
   Yonghong Song.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
  bpf: btf: Remove two unused function declarations
  bpf: lru: Remove unused declaration bpf_lru_promote()
  selftests/bpf: relax expected log messages to allow emitting BPF_ST
  selftests/bpf: remove duplicated functions
  bpf, docs: Fix small typo and define semantics of sign extension
  selftests/bpf: Add bpf_get_func_ip test for uprobe inside function
  selftests/bpf: Add bpf_get_func_ip tests for uprobe on function entry
  bpf: Add support for bpf_get_func_ip helper for uprobe program
  selftests/bpf: Add a movsx selftest for sign-extension of R10
  bpf: Fix an incorrect verification success with movsx insn
  bpf, docs: Formalize type notation and function semantics in ISA standard
  bpf: change bpf_alu_sign_string and bpf_movsx_string to static
  libbpf: Use local includes inside the library
  bpf: fix bpf_dynptr_slice() to stop return an ERR_PTR.
  bpf: fix inconsistent return types of bpf_xdp_copy_buf().
  selftests/bpf: fix the incorrect verification of port numbers.
  selftests/bpf: Add test for detachment on empty mprog entry
  bpf: Fix mprog detachment for empty mprog entry
  bpf: bpf_struct_ops: Remove unnecessary initial values of variables
====================

Link: https://lore.kernel.org/r/20230810055123.109578-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

11 files changed, 206 insertions, 91 deletions

diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 70da85200695..d21deb46f49f 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -5086,9 +5086,14 @@ union bpf_attr {
  * u64 bpf_get_func_ip(void *ctx)
  * 	Description
  * 		Get address of the traced function (for tracing and kprobe programs).
+ *
+ * 		When called for kprobe program attached as uprobe it returns
+ * 		probe address for both entry and return uprobe.
+ *
  * 	Return
- * 		Address of the traced function.
+ * 		Address of the traced function for kprobe.
  * 		0 for kprobes placed within the function (not at the entry).
+ * 		Address of the probe for uprobe and return uprobe.
  *
  * u64 bpf_get_attach_cookie(void *ctx)
  * 	Description
diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h
index be076a4041ab..3803479dbe10 100644
--- a/tools/lib/bpf/bpf_tracing.h
+++ b/tools/lib/bpf/bpf_tracing.h
@@ -2,7 +2,7 @@
 #ifndef __BPF_TRACING_H__
 #define __BPF_TRACING_H__
 
-#include <bpf/bpf_helpers.h>
+#include "bpf_helpers.h"
 
 /* Scan the ARCH passed in from ARCH env variable (see Makefile) */
 #if defined(__TARGET_ARCH_x86)
diff --git a/tools/lib/bpf/usdt.bpf.h b/tools/lib/bpf/usdt.bpf.h
index 0bd4c135acc2..f6763300b26a 100644
--- a/tools/lib/bpf/usdt.bpf.h
+++ b/tools/lib/bpf/usdt.bpf.h
@@ -4,8 +4,8 @@
 #define __USDT_BPF_H__
 
 #include <linux/errno.h>
-#include <bpf/bpf_helpers.h>
-#include <bpf/bpf_tracing.h>
+#include "bpf_helpers.h"
+#include "bpf_tracing.h"
 
 /* Below types and maps are internal implementation details of libbpf's USDT
  * support and are subjects to change. Also, bpf_usdt_xxx() API helpers should
diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_tcp_skb.c b/tools/testing/selftests/bpf/prog_tests/cgroup_tcp_skb.c
index 95bab61a1e57..a1542faf7873 100644
--- a/tools/testing/selftests/bpf/prog_tests/cgroup_tcp_skb.c
+++ b/tools/testing/selftests/bpf/prog_tests/cgroup_tcp_skb.c
@@ -9,6 +9,7 @@
 #include "testing_helpers.h"
 #include "cgroup_tcp_skb.skel.h"
 #include "cgroup_tcp_skb.h"
+#include "network_helpers.h"
 
 #define CGROUP_TCP_SKB_PATH "/test_cgroup_tcp_skb"
 
@@ -58,79 +59,13 @@ static int create_client_sock_v6(void)
 	return fd;
 }
 
-static int create_server_sock_v6(void)
-{
-	struct sockaddr_in6 addr = {
-		.sin6_family = AF_INET6,
-		.sin6_port = htons(0),
-		.sin6_addr = IN6ADDR_LOOPBACK_INIT,
-	};
-	int fd, err;
-
-	fd = socket(AF_INET6, SOCK_STREAM, 0);
-	if (fd < 0) {
-		perror("socket");
-		return -1;
-	}
-
-	err = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
-	if (err < 0) {
-		perror("bind");
-		return -1;
-	}
-
-	err = listen(fd, 1);
-	if (err < 0) {
-		perror("listen");
-		return -1;
-	}
-
-	return fd;
-}
-
-static int get_sock_port_v6(int fd)
-{
-	struct sockaddr_in6 addr;
-	socklen_t len;
-	int err;
-
-	len = sizeof(addr);
-	err = getsockname(fd, (struct sockaddr *)&addr, &len);
-	if (err < 0) {
-		perror("getsockname");
-		return -1;
-	}
-
-	return ntohs(addr.sin6_port);
-}
-
-static int connect_client_server_v6(int client_fd, int listen_fd)
-{
-	struct sockaddr_in6 addr = {
-		.sin6_family = AF_INET6,
-		.sin6_addr = IN6ADDR_LOOPBACK_INIT,
-	};
-	int err;
-
-	addr.sin6_port = htons(get_sock_port_v6(listen_fd));
-	if (addr.sin6_port < 0)
-		return -1;
-
-	err = connect(client_fd, (struct sockaddr *)&addr, sizeof(addr));
-	if (err < 0) {
-		perror("connect");
-		return -1;
-	}
-
-	return 0;
-}
-
 /* Connect to the server in a cgroup from the outside of the cgroup. */
 static int talk_to_cgroup(int *client_fd, int *listen_fd, int *service_fd,
 			  struct cgroup_tcp_skb *skel)
 {
 	int err, cp;
 	char buf[5];
+	int port;
 
 	/* Create client & server socket */
 	err = join_root_cgroup();
@@ -142,14 +77,17 @@ static int talk_to_cgroup(int *client_fd, int *listen_fd, int *service_fd,
 	err = join_cgroup(CGROUP_TCP_SKB_PATH);
 	if (!ASSERT_OK(err, "join_cgroup"))
 		return -1;
-	*listen_fd = create_server_sock_v6();
+	*listen_fd = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
 	if (!ASSERT_GE(*listen_fd, 0, "listen_fd"))
 		return -1;
-	skel->bss->g_sock_port = get_sock_port_v6(*listen_fd);
+	port = get_socket_local_port(*listen_fd);
+	if (!ASSERT_GE(port, 0, "get_socket_local_port"))
+		return -1;
+	skel->bss->g_sock_port = ntohs(port);
 
 	/* Connect client to server */
-	err = connect_client_server_v6(*client_fd, *listen_fd);
-	if (!ASSERT_OK(err, "connect_client_server_v6"))
+	err = connect_fd_to_fd(*client_fd, *listen_fd, 0);
+	if (!ASSERT_OK(err, "connect_fd_to_fd"))
 		return -1;
 	*service_fd = accept(*listen_fd, NULL, NULL);
 	if (!ASSERT_GE(*service_fd, 0, "service_fd"))
@@ -174,12 +112,13 @@ static int talk_to_outside(int *client_fd, int *listen_fd, int *service_fd,
 {
 	int err, cp;
 	char buf[5];
+	int port;
 
 	/* Create client & server socket */
 	err = join_root_cgroup();
 	if (!ASSERT_OK(err, "join_root_cgroup"))
 		return -1;
-	*listen_fd = create_server_sock_v6();
+	*listen_fd = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
 	if (!ASSERT_GE(*listen_fd, 0, "listen_fd"))
 		return -1;
 	err = join_cgroup(CGROUP_TCP_SKB_PATH);
@@ -191,11 +130,14 @@ static int talk_to_outside(int *client_fd, int *listen_fd, int *service_fd,
 	err = join_root_cgroup();
 	if (!ASSERT_OK(err, "join_root_cgroup"))
 		return -1;
-	skel->bss->g_sock_port = get_sock_port_v6(*listen_fd);
+	port = get_socket_local_port(*listen_fd);
+	if (!ASSERT_GE(port, 0, "get_socket_local_port"))
+		return -1;
+	skel->bss->g_sock_port = ntohs(port);
 
 	/* Connect client to server */
-	err = connect_client_server_v6(*client_fd, *listen_fd);
-	if (!ASSERT_OK(err, "connect_client_server_v6"))
+	err = connect_fd_to_fd(*client_fd, *listen_fd, 0);
+	if (!ASSERT_OK(err, "connect_fd_to_fd"))
 		return -1;
 	*service_fd = accept(*listen_fd, NULL, NULL);
 	if (!ASSERT_GE(*service_fd, 0, "service_fd"))
diff --git a/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c b/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c
index fede8ef58b5b..c40242dfa8fb 100644
--- a/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c
+++ b/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c
@@ -1,6 +1,11 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <test_progs.h>
 #include "get_func_ip_test.skel.h"
+#include "get_func_ip_uprobe_test.skel.h"
+
+static noinline void uprobe_trigger(void)
+{
+}
 
 static void test_function_entry(void)
 {
@@ -20,6 +25,8 @@ static void test_function_entry(void)
 	if (!ASSERT_OK(err, "get_func_ip_test__attach"))
 		goto cleanup;
 
+	skel->bss->uprobe_trigger = (unsigned long) uprobe_trigger;
+
 	prog_fd = bpf_program__fd(skel->progs.test1);
 	err = bpf_prog_test_run_opts(prog_fd, &topts);
 	ASSERT_OK(err, "test_run");
@@ -30,21 +37,31 @@ static void test_function_entry(void)
 
 	ASSERT_OK(err, "test_run");
 
+	uprobe_trigger();
+
 	ASSERT_EQ(skel->bss->test1_result, 1, "test1_result");
 	ASSERT_EQ(skel->bss->test2_result, 1, "test2_result");
 	ASSERT_EQ(skel->bss->test3_result, 1, "test3_result");
 	ASSERT_EQ(skel->bss->test4_result, 1, "test4_result");
 	ASSERT_EQ(skel->bss->test5_result, 1, "test5_result");
+	ASSERT_EQ(skel->bss->test7_result, 1, "test7_result");
+	ASSERT_EQ(skel->bss->test8_result, 1, "test8_result");
 
 cleanup:
 	get_func_ip_test__destroy(skel);
 }
 
-/* test6 is x86_64 specific because of the instruction
- * offset, disabling it for all other archs
- */
 #ifdef __x86_64__
-static void test_function_body(void)
+extern void uprobe_trigger_body(void);
+asm(
+".globl uprobe_trigger_body\n"
+".type uprobe_trigger_body, @function\n"
+"uprobe_trigger_body:\n"
+"	nop\n"
+"	ret\n"
+);
+
+static void test_function_body_kprobe(void)
 {
 	struct get_func_ip_test *skel = NULL;
 	LIBBPF_OPTS(bpf_test_run_opts, topts);
@@ -56,6 +73,9 @@ static void test_function_body(void)
 	if (!ASSERT_OK_PTR(skel, "get_func_ip_test__open"))
 		return;
 
+	/* test6 is x86_64 specific and is disabled by default,
+	 * enable it for body test.
+	 */
 	bpf_program__set_autoload(skel->progs.test6, true);
 
 	err = get_func_ip_test__load(skel);
@@ -79,6 +99,35 @@ cleanup:
 	bpf_link__destroy(link6);
 	get_func_ip_test__destroy(skel);
 }
+
+static void test_function_body_uprobe(void)
+{
+	struct get_func_ip_uprobe_test *skel = NULL;
+	int err;
+
+	skel = get_func_ip_uprobe_test__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "get_func_ip_uprobe_test__open_and_load"))
+		return;
+
+	err = get_func_ip_uprobe_test__attach(skel);
+	if (!ASSERT_OK(err, "get_func_ip_test__attach"))
+		goto cleanup;
+
+	skel->bss->uprobe_trigger_body = (unsigned long) uprobe_trigger_body;
+
+	uprobe_trigger_body();
+
+	ASSERT_EQ(skel->bss->test1_result, 1, "test1_result");
+
+cleanup:
+	get_func_ip_uprobe_test__destroy(skel);
+}
+
+static void test_function_body(void)
+{
+	test_function_body_kprobe();
+	test_function_body_uprobe();
+}
 #else
 #define test_function_body()
 #endif
diff --git a/tools/testing/selftests/bpf/prog_tests/log_fixup.c b/tools/testing/selftests/bpf/prog_tests/log_fixup.c
index dba71d98a227..effd78b2a657 100644
--- a/tools/testing/selftests/bpf/prog_tests/log_fixup.c
+++ b/tools/testing/selftests/bpf/prog_tests/log_fixup.c
@@ -124,7 +124,7 @@ static void missing_map(void)
 	ASSERT_FALSE(bpf_map__autocreate(skel->maps.missing_map), "missing_map_autocreate");
 
 	ASSERT_HAS_SUBSTR(log_buf,
-			  "8: <invalid BPF map reference>\n"
+			  ": <invalid BPF map reference>\n"
 			  "BPF map 'missing_map' is referenced but wasn't created\n",
 			  "log_buf");
 
diff --git a/tools/testing/selftests/bpf/prog_tests/spin_lock.c b/tools/testing/selftests/bpf/prog_tests/spin_lock.c
index d9270bd3d920..f29c08d93beb 100644
--- a/tools/testing/selftests/bpf/prog_tests/spin_lock.c
+++ b/tools/testing/selftests/bpf/prog_tests/spin_lock.c
@@ -1,4 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <regex.h>
 #include <test_progs.h>
 #include <network_helpers.h>
 
@@ -19,12 +20,16 @@ static struct {
 	  "; R1_w=map_value(off=0,ks=4,vs=4,imm=0)\n2: (85) call bpf_this_cpu_ptr#154\n"
 	  "R1 type=map_value expected=percpu_ptr_" },
 	{ "lock_id_mapval_preserve",
-	  "8: (bf) r1 = r0                       ; R0_w=map_value(id=1,off=0,ks=4,vs=8,imm=0) "
-	  "R1_w=map_value(id=1,off=0,ks=4,vs=8,imm=0)\n9: (85) call bpf_this_cpu_ptr#154\n"
+	  "[0-9]\\+: (bf) r1 = r0                       ;"
+	  " R0_w=map_value(id=1,off=0,ks=4,vs=8,imm=0)"
+	  " R1_w=map_value(id=1,off=0,ks=4,vs=8,imm=0)\n"
+	  "[0-9]\\+: (85) call bpf_this_cpu_ptr#154\n"
 	  "R1 type=map_value expected=percpu_ptr_" },
 	{ "lock_id_innermapval_preserve",
-	  "13: (bf) r1 = r0                      ; R0=map_value(id=2,off=0,ks=4,vs=8,imm=0) "
-	  "R1_w=map_value(id=2,off=0,ks=4,vs=8,imm=0)\n14: (85) call bpf_this_cpu_ptr#154\n"
+	  "[0-9]\\+: (bf) r1 = r0                      ;"
+	  " R0=map_value(id=2,off=0,ks=4,vs=8,imm=0)"
+	  " R1_w=map_value(id=2,off=0,ks=4,vs=8,imm=0)\n"
+	  "[0-9]\\+: (85) call bpf_this_cpu_ptr#154\n"
 	  "R1 type=map_value expected=percpu_ptr_" },
 	{ "lock_id_mismatch_kptr_kptr", "bpf_spin_unlock of different lock" },
 	{ "lock_id_mismatch_kptr_global", "bpf_spin_unlock of different lock" },
@@ -45,6 +50,24 @@ static struct {
 	{ "lock_id_mismatch_innermapval_mapval", "bpf_spin_unlock of different lock" },
 };
 
+static int match_regex(const char *pattern, const char *string)
+{
+	int err, rc;
+	regex_t re;
+
+	err = regcomp(&re, pattern, REG_NOSUB);
+	if (err) {
+		char errbuf[512];
+
+		regerror(err, &re, errbuf, sizeof(errbuf));
+		PRINT_FAIL("Can't compile regex: %s\n", errbuf);
+		return -1;
+	}
+	rc = regexec(&re, string, 0, NULL, 0);
+	regfree(&re);
+	return rc == 0 ? 1 : 0;
+}
+
 static void test_spin_lock_fail_prog(const char *prog_name, const char *err_msg)
 {
 	LIBBPF_OPTS(bpf_object_open_opts, opts, .kernel_log_buf = log_buf,
@@ -74,7 +97,11 @@ static void test_spin_lock_fail_prog(const char *prog_name, const char *err_msg)
 		goto end;
 	}
 
-	if (!ASSERT_OK_PTR(strstr(log_buf, err_msg), "expected error message")) {
+	ret = match_regex(err_msg, log_buf);
+	if (!ASSERT_GE(ret, 0, "match_regex"))
+		goto end;
+
+	if (!ASSERT_TRUE(ret, "no match for expected error message")) {
 		fprintf(stderr, "Expected: %s\n", err_msg);
 		fprintf(stderr, "Verifier: %s\n", log_buf);
 	}
diff --git a/tools/testing/selftests/bpf/prog_tests/tc_opts.c b/tools/testing/selftests/bpf/prog_tests/tc_opts.c
index 7914100f9b46..39bd253e41aa 100644
--- a/tools/testing/selftests/bpf/prog_tests/tc_opts.c
+++ b/tools/testing/selftests/bpf/prog_tests/tc_opts.c
@@ -2237,3 +2237,34 @@ void serial_test_tc_opts_detach_after(void)
 	test_tc_opts_detach_after_target(BPF_TCX_INGRESS);
 	test_tc_opts_detach_after_target(BPF_TCX_EGRESS);
 }
+
+static void test_tc_opts_delete_empty(int target, bool chain_tc_old)
+{
+	LIBBPF_OPTS(bpf_tc_hook, tc_hook, .ifindex = loopback);
+	LIBBPF_OPTS(bpf_prog_detach_opts, optd);
+	int err;
+
+	assert_mprog_count(target, 0);
+	if (chain_tc_old) {
+		tc_hook.attach_point = target == BPF_TCX_INGRESS ?
+				       BPF_TC_INGRESS : BPF_TC_EGRESS;
+		err = bpf_tc_hook_create(&tc_hook);
+		ASSERT_OK(err, "bpf_tc_hook_create");
+		__assert_mprog_count(target, 0, true, loopback);
+	}
+	err = bpf_prog_detach_opts(0, loopback, target, &optd);
+	ASSERT_EQ(err, -ENOENT, "prog_detach");
+	if (chain_tc_old) {
+		tc_hook.attach_point = BPF_TC_INGRESS | BPF_TC_EGRESS;
+		bpf_tc_hook_destroy(&tc_hook);
+	}
+	assert_mprog_count(target, 0);
+}
+
+void serial_test_tc_opts_delete_empty(void)
+{
+	test_tc_opts_delete_empty(BPF_TCX_INGRESS, false);
+	test_tc_opts_delete_empty(BPF_TCX_EGRESS, false);
+	test_tc_opts_delete_empty(BPF_TCX_INGRESS, true);
+	test_tc_opts_delete_empty(BPF_TCX_EGRESS, true);
+}
diff --git a/tools/testing/selftests/bpf/progs/get_func_ip_test.c b/tools/testing/selftests/bpf/progs/get_func_ip_test.c
index 8559e698b40d..8956eb78a226 100644
--- a/tools/testing/selftests/bpf/progs/get_func_ip_test.c
+++ b/tools/testing/selftests/bpf/progs/get_func_ip_test.c
@@ -1,8 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
-#include <linux/bpf.h>
+#include "vmlinux.h"
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
-#include <stdbool.h>
 
 char _license[] SEC("license") = "GPL";
 
@@ -83,3 +82,25 @@ int test6(struct pt_regs *ctx)
 	test6_result = (const void *) addr == 0;
 	return 0;
 }
+
+unsigned long uprobe_trigger;
+
+__u64 test7_result = 0;
+SEC("uprobe//proc/self/exe:uprobe_trigger")
+int BPF_UPROBE(test7)
+{
+	__u64 addr = bpf_get_func_ip(ctx);
+
+	test7_result = (const void *) addr == (const void *) uprobe_trigger;
+	return 0;
+}
+
+__u64 test8_result = 0;
+SEC("uretprobe//proc/self/exe:uprobe_trigger")
+int BPF_URETPROBE(test8, int ret)
+{
+	__u64 addr = bpf_get_func_ip(ctx);
+
+	test8_result = (const void *) addr == (const void *) uprobe_trigger;
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/get_func_ip_uprobe_test.c b/tools/testing/selftests/bpf/progs/get_func_ip_uprobe_test.c
new file mode 100644
index 000000000000..052f8a4345a8
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/get_func_ip_uprobe_test.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+unsigned long uprobe_trigger_body;
+
+__u64 test1_result = 0;
+SEC("uprobe//proc/self/exe:uprobe_trigger_body+1")
+int BPF_UPROBE(test1)
+{
+	__u64 addr = bpf_get_func_ip(ctx);
+
+	test1_result = (const void *) addr == (const void *) uprobe_trigger_body + 1;
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/verifier_movsx.c b/tools/testing/selftests/bpf/progs/verifier_movsx.c
index 9568089932d7..be6f69a6b659 100644
--- a/tools/testing/selftests/bpf/progs/verifier_movsx.c
+++ b/tools/testing/selftests/bpf/progs/verifier_movsx.c
@@ -198,6 +198,28 @@ l0_%=:							\
 	: __clobber_all);
 }
 
+SEC("socket")
+__description("MOV64SX, S16, R10 Sign Extension")
+__failure __msg("R1 type=scalar expected=fp, pkt, pkt_meta, map_key, map_value, mem, ringbuf_mem, buf, trusted_ptr_")
+__failure_unpriv __msg_unpriv("R10 sign-extension part of pointer")
+__naked void mov64sx_s16_r10(void)
+{
+	asm volatile ("					\
+	r1 = 553656332;					\
+	*(u32 *)(r10 - 8) = r1; 			\
+	r1 = (s16)r10;					\
+	r1 += -8;					\
+	r2 = 3;						\
+	if r2 <= r1 goto l0_%=;				\
+l0_%=:							\
+	call %[bpf_trace_printk];			\
+	r0 = 0;						\
+	exit;						\
+"	:
+	: __imm(bpf_trace_printk)
+	: __clobber_all);
+}
+
 #else
 
 SEC("socket")