From d1f90bcdc7cf95cf442321f18452d0367e80b7d5 Mon Sep 17 00:00:00 2001

From: "Dmitry V. Levin" <ldv@altlinux.org>

Date: Tue, 12 Mar 2019 11:17:20 +0000

Subject: [PATCH] bpf: add support for *jited_ksyms and *jited_func_lens fields

 in struct bpf_prog_info

* bpf_attr.h (struct bpf_prog_info_struct): Add nr_jited_ksyms,

nr_jited_func_lens, jited_ksyms, and jited_func_lens fields.

* bpf.c (struct obj_get_info_saved): Likewise.

(print_bpf_prog_info): Decode these fields introduced by Linux commits

v4.18-rc1~114^2~148^2~3^2~6 and v4.18-rc1~114^2~148^2~3^2~2.

* tests/bpf-obj_get_info_by_fd.c (main): Update expected output.

---

 bpf.c                          | 40 ++++++++++++++++++++++++++++++++++++++++

 bpf_attr.h                     |  6 +++++-

 tests/bpf-obj_get_info_by_fd.c | 21 +++++++++++++++++++++

 3 files changed, 66 insertions(+), 1 deletion(-)

Index: strace-4.24/bpf.c

===================================================================

--- strace-4.24.orig/bpf.c	2020-01-28 00:15:59.919446522 +0100

+++ strace-4.24/bpf.c	2020-01-28 00:16:27.823183735 +0100

@@ -427,6 +427,11 @@

 	uint32_t jited_prog_len;

 	uint32_t xlated_prog_len;

 	uint32_t nr_map_ids;

+

+	uint32_t nr_jited_ksyms;

+	uint32_t nr_jited_func_lens;

+	uint64_t jited_ksyms;

+	uint64_t jited_func_lens;

 };

 static void

@@ -497,6 +502,10 @@

 		saved->jited_prog_len = info.jited_prog_len;

 		saved->xlated_prog_len = info.xlated_prog_len;

 		saved->nr_map_ids = info.nr_map_ids;

+		saved->nr_jited_ksyms = info.nr_jited_ksyms;

+		saved->nr_jited_func_lens = info.nr_jited_func_lens;

+		saved->jited_ksyms = info.jited_ksyms;

+		saved->jited_func_lens = info.jited_func_lens;

 		return;

 	}

@@ -559,6 +568,37 @@

 	PRINT_FIELD_DEV(", ", info, netns_dev);

 	PRINT_FIELD_U(", ", info, netns_ino);

+	/*

+	 * The next four fields were introduced by Linux commits

+	 * v4.18-rc1~114^2~148^2~3^2~6 and v4.18-rc1~114^2~148^2~3^2~2.

+	 */

+	if (len <= offsetof(struct bpf_prog_info_struct, nr_jited_ksyms))

+		goto print_bpf_prog_info_end;

+

+	tprints(", nr_jited_ksyms=");

+	if (saved->nr_jited_ksyms != info.nr_jited_ksyms)

+		tprintf("%" PRIu32 " => ", saved->nr_jited_ksyms);

+	tprintf("%" PRIu32, info.nr_jited_ksyms);

+

+	tprints(", nr_jited_func_lens=");

+	if (saved->nr_jited_func_lens != info.nr_jited_func_lens)

+		tprintf("%" PRIu32 " => ", saved->nr_jited_func_lens);

+	tprintf("%" PRIu32, info.nr_jited_func_lens);

+

+	tprints(", jited_ksyms=");

+	if (saved->jited_ksyms != info.jited_ksyms) {

+		printaddr64(saved->jited_ksyms);

+		tprints(" => ");

+	}

+	printaddr64(info.jited_ksyms);

+

+	tprints(", jited_func_lens=");

+	if (saved->jited_func_lens != info.jited_func_lens) {

+		printaddr64(saved->jited_func_lens);

+		tprints(" => ");

+	}

+	printaddr64(info.jited_func_lens);

+

 	decode_attr_extra_data(tcp, info_buf, size, bpf_prog_info_struct_size);

 print_bpf_prog_info_end:

Index: strace-4.24/bpf_attr.h

===================================================================

--- strace-4.24.orig/bpf_attr.h	2020-01-28 00:15:59.919446522 +0100

+++ strace-4.24/bpf_attr.h	2020-01-28 00:16:27.823183735 +0100

@@ -272,10 +272,14 @@

 	 */

 	uint64_t ATTRIBUTE_ALIGNED(8) netns_dev; /* skip check */

 	uint64_t ATTRIBUTE_ALIGNED(8) netns_ino; /* skip check */

+	uint32_t nr_jited_ksyms;

+	uint32_t nr_jited_func_lens;

+	uint64_t ATTRIBUTE_ALIGNED(8) jited_ksyms;

+	uint64_t ATTRIBUTE_ALIGNED(8) jited_func_lens;

 };

 # define bpf_prog_info_struct_size \

 	sizeof(struct bpf_prog_info_struct)

-# define expected_bpf_prog_info_struct_size 104

+# define expected_bpf_prog_info_struct_size 128

 #endif /* !STRACE_BPF_ATTR_H */

Index: strace-4.24/tests/bpf-obj_get_info_by_fd.c

===================================================================

--- strace-4.24.orig/tests/bpf-obj_get_info_by_fd.c	2020-01-28 00:15:59.920446513 +0100

+++ strace-4.24/tests/bpf-obj_get_info_by_fd.c	2020-01-28 00:16:27.823183735 +0100

@@ -358,6 +358,8 @@

 	memset(prog_info, 0, PROG_INFO_SZ);

 	for (unsigned int i = 0; i < 4; i++) {

 		prog_info->jited_prog_len = 0;

+		prog_info->nr_jited_ksyms = 0;

+		prog_info->nr_jited_func_lens = 0;

 		memset(prog_info + 1, 0, PROG_INFO_SZ - sizeof(*prog_info));

 		switch (i) {

 		case 1:

@@ -485,6 +487,25 @@

 		    offsetof(struct bpf_prog_info_struct, netns_ino))

 			printf(", netns_ino=%" PRIu64, prog_info->netns_ino);

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, nr_jited_ksyms)) {

+			printf(", nr_jited_ksyms=0");

+			if (prog_info->nr_jited_ksyms)

+				printf(" => %u", prog_info->nr_jited_ksyms);

+		}

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, nr_jited_func_lens)) {

+			printf(", nr_jited_func_lens=0");

+			if (prog_info->nr_jited_func_lens)

+				printf(" => %u", prog_info->nr_jited_func_lens);

+		}

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, jited_ksyms))

+			printf(", jited_ksyms=NULL");

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, jited_func_lens))

+			printf(", jited_func_lens=NULL");

+

 		printf("}");

 # else /* !VERBOSE */

 		printf("%p", prog_info);

Index: strace-4.24/tests-m32/bpf-obj_get_info_by_fd.c

===================================================================

--- strace-4.24.orig/tests-m32/bpf-obj_get_info_by_fd.c	2020-01-28 00:16:14.855305862 +0100

+++ strace-4.24/tests-m32/bpf-obj_get_info_by_fd.c	2020-01-28 00:16:37.300094485 +0100

@@ -358,6 +358,8 @@

 	memset(prog_info, 0, PROG_INFO_SZ);

 	for (unsigned int i = 0; i < 4; i++) {

 		prog_info->jited_prog_len = 0;

+		prog_info->nr_jited_ksyms = 0;

+		prog_info->nr_jited_func_lens = 0;

 		memset(prog_info + 1, 0, PROG_INFO_SZ - sizeof(*prog_info));

 		switch (i) {

 		case 1:

@@ -485,6 +487,25 @@

 		    offsetof(struct bpf_prog_info_struct, netns_ino))

 			printf(", netns_ino=%" PRIu64, prog_info->netns_ino);

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, nr_jited_ksyms)) {

+			printf(", nr_jited_ksyms=0");

+			if (prog_info->nr_jited_ksyms)

+				printf(" => %u", prog_info->nr_jited_ksyms);

+		}

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, nr_jited_func_lens)) {

+			printf(", nr_jited_func_lens=0");

+			if (prog_info->nr_jited_func_lens)

+				printf(" => %u", prog_info->nr_jited_func_lens);

+		}

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, jited_ksyms))

+			printf(", jited_ksyms=NULL");

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, jited_func_lens))

+			printf(", jited_func_lens=NULL");

+

 		printf("}");

 # else /* !VERBOSE */

 		printf("%p", prog_info);

Index: strace-4.24/tests-mx32/bpf-obj_get_info_by_fd.c

===================================================================

--- strace-4.24.orig/tests-mx32/bpf-obj_get_info_by_fd.c	2020-01-28 00:16:23.096228252 +0100

+++ strace-4.24/tests-mx32/bpf-obj_get_info_by_fd.c	2020-01-28 00:16:34.082124791 +0100

@@ -358,6 +358,8 @@

 	memset(prog_info, 0, PROG_INFO_SZ);

 	for (unsigned int i = 0; i < 4; i++) {

 		prog_info->jited_prog_len = 0;

+		prog_info->nr_jited_ksyms = 0;

+		prog_info->nr_jited_func_lens = 0;

 		memset(prog_info + 1, 0, PROG_INFO_SZ - sizeof(*prog_info));

 		switch (i) {

 		case 1:

@@ -485,6 +487,25 @@

 		    offsetof(struct bpf_prog_info_struct, netns_ino))

 			printf(", netns_ino=%" PRIu64, prog_info->netns_ino);

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, nr_jited_ksyms)) {

+			printf(", nr_jited_ksyms=0");

+			if (prog_info->nr_jited_ksyms)

+				printf(" => %u", prog_info->nr_jited_ksyms);

+		}

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, nr_jited_func_lens)) {

+			printf(", nr_jited_func_lens=0");

+			if (prog_info->nr_jited_func_lens)

+				printf(" => %u", prog_info->nr_jited_func_lens);

+		}

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, jited_ksyms))

+			printf(", jited_ksyms=NULL");

+		if (bpf_prog_get_info_attr.info_len >

+		    offsetof(struct bpf_prog_info_struct, jited_func_lens))

+			printf(", jited_func_lens=NULL");

+

 		printf("}");

 # else /* !VERBOSE */

 		printf("%p", prog_info);