Vicent Marti | 411f698 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2016 GitHub, Inc. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 16 | #include <sys/types.h> |
| 17 | #include <sys/stat.h> |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 18 | #include <sys/mman.h> |
Teng Qin | 1670d33 | 2017-10-06 18:08:33 -0700 | [diff] [blame] | 19 | #include <errno.h> |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 20 | #include <fcntl.h> |
| 21 | #include <unistd.h> |
| 22 | #include <string.h> |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 23 | #include <libgen.h> |
| 24 | #include <stdio.h> |
| 25 | #include <stdlib.h> |
| 26 | #include <limits.h> |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 27 | |
| 28 | #include <gelf.h> |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 29 | #include "bcc_elf.h" |
Teng Qin | 1670d33 | 2017-10-06 18:08:33 -0700 | [diff] [blame] | 30 | #include "bcc_proc.h" |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 31 | #include "bcc_syms.h" |
| 32 | |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 33 | #define NT_STAPSDT 3 |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 34 | #define ELF_ST_TYPE(x) (((uint32_t) x) & 0xf) |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 35 | |
Teng Qin | 1670d33 | 2017-10-06 18:08:33 -0700 | [diff] [blame] | 36 | static int openelf_fd(int fd, Elf **elf_out) { |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 37 | if (elf_version(EV_CURRENT) == EV_NONE) |
| 38 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 39 | |
Teng Qin | 1670d33 | 2017-10-06 18:08:33 -0700 | [diff] [blame] | 40 | *elf_out = elf_begin(fd, ELF_C_READ, 0); |
| 41 | if (*elf_out == NULL) |
| 42 | return -1; |
| 43 | |
| 44 | return 0; |
| 45 | } |
| 46 | |
| 47 | static int openelf(const char *path, Elf **elf_out, int *fd_out) { |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 48 | *fd_out = open(path, O_RDONLY); |
| 49 | if (*fd_out < 0) |
| 50 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 51 | |
Teng Qin | 1670d33 | 2017-10-06 18:08:33 -0700 | [diff] [blame] | 52 | if (openelf_fd(*fd_out, elf_out) == -1) { |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 53 | close(*fd_out); |
| 54 | return -1; |
| 55 | } |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 56 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 57 | return 0; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 58 | } |
| 59 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 60 | static const char *parse_stapsdt_note(struct bcc_elf_usdt *probe, |
| 61 | const char *desc, int elf_class) { |
| 62 | if (elf_class == ELFCLASS32) { |
| 63 | probe->pc = *((uint32_t *)(desc)); |
| 64 | probe->base_addr = *((uint32_t *)(desc + 4)); |
| 65 | probe->semaphore = *((uint32_t *)(desc + 8)); |
| 66 | desc = desc + 12; |
| 67 | } else { |
| 68 | probe->pc = *((uint64_t *)(desc)); |
| 69 | probe->base_addr = *((uint64_t *)(desc + 8)); |
| 70 | probe->semaphore = *((uint64_t *)(desc + 16)); |
| 71 | desc = desc + 24; |
| 72 | } |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 73 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 74 | probe->provider = desc; |
| 75 | desc += strlen(desc) + 1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 76 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 77 | probe->name = desc; |
| 78 | desc += strlen(desc) + 1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 79 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 80 | probe->arg_fmt = desc; |
| 81 | desc += strlen(desc) + 1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 82 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 83 | return desc; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 84 | } |
| 85 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 86 | static int do_note_segment(Elf_Scn *section, int elf_class, |
| 87 | bcc_elf_probecb callback, const char *binpath, |
Yonghong Song | bf2a811 | 2018-01-11 11:45:11 -0800 | [diff] [blame] | 88 | uint64_t first_inst_offset, void *payload) { |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 89 | Elf_Data *data = NULL; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 90 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 91 | while ((data = elf_getdata(section, data)) != 0) { |
| 92 | size_t offset = 0; |
| 93 | GElf_Nhdr hdr; |
| 94 | size_t name_off, desc_off; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 95 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 96 | while ((offset = gelf_getnote(data, offset, &hdr, &name_off, &desc_off)) != |
| 97 | 0) { |
| 98 | const char *desc, *desc_end; |
| 99 | struct bcc_elf_usdt probe; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 100 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 101 | if (hdr.n_type != NT_STAPSDT) |
| 102 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 103 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 104 | if (hdr.n_namesz != 8) |
| 105 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 106 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 107 | if (memcmp((const char *)data->d_buf + name_off, "stapsdt", 8) != 0) |
| 108 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 109 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 110 | desc = (const char *)data->d_buf + desc_off; |
| 111 | desc_end = desc + hdr.n_descsz; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 112 | |
Yonghong Song | bf2a811 | 2018-01-11 11:45:11 -0800 | [diff] [blame] | 113 | if (parse_stapsdt_note(&probe, desc, elf_class) == desc_end) { |
| 114 | if (probe.pc < first_inst_offset) |
| 115 | fprintf(stderr, |
| 116 | "WARNING: invalid address 0x%lx for probe (%s,%s) in binary %s\n", |
| 117 | probe.pc, probe.provider, probe.name, binpath); |
| 118 | else |
| 119 | callback(binpath, &probe, payload); |
| 120 | } |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 121 | } |
| 122 | } |
| 123 | return 0; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 124 | } |
| 125 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 126 | static int listprobes(Elf *e, bcc_elf_probecb callback, const char *binpath, |
| 127 | void *payload) { |
| 128 | Elf_Scn *section = NULL; |
| 129 | size_t stridx; |
| 130 | int elf_class = gelf_getclass(e); |
Yonghong Song | bf2a811 | 2018-01-11 11:45:11 -0800 | [diff] [blame] | 131 | uint64_t first_inst_offset = 0; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 132 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 133 | if (elf_getshdrstrndx(e, &stridx) != 0) |
| 134 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 135 | |
Yonghong Song | bf2a811 | 2018-01-11 11:45:11 -0800 | [diff] [blame] | 136 | // Get the offset to the first instruction |
| 137 | while ((section = elf_nextscn(e, section)) != 0) { |
| 138 | GElf_Shdr header; |
| 139 | |
| 140 | if (!gelf_getshdr(section, &header)) |
| 141 | continue; |
| 142 | |
| 143 | // The elf file section layout is based on increasing virtual address, |
| 144 | // getting the first section with SHF_EXECINSTR is enough. |
| 145 | if (header.sh_flags & SHF_EXECINSTR) { |
| 146 | first_inst_offset = header.sh_addr; |
| 147 | break; |
| 148 | } |
| 149 | } |
| 150 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 151 | while ((section = elf_nextscn(e, section)) != 0) { |
| 152 | GElf_Shdr header; |
| 153 | char *name; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 154 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 155 | if (!gelf_getshdr(section, &header)) |
| 156 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 157 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 158 | if (header.sh_type != SHT_NOTE) |
| 159 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 160 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 161 | name = elf_strptr(e, stridx, header.sh_name); |
| 162 | if (name && !strcmp(name, ".note.stapsdt")) { |
Yonghong Song | bf2a811 | 2018-01-11 11:45:11 -0800 | [diff] [blame] | 163 | if (do_note_segment(section, elf_class, callback, binpath, |
| 164 | first_inst_offset, payload) < 0) |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 165 | return -1; |
| 166 | } |
| 167 | } |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 168 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 169 | return 0; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 170 | } |
| 171 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 172 | int bcc_elf_foreach_usdt(const char *path, bcc_elf_probecb callback, |
| 173 | void *payload) { |
| 174 | Elf *e; |
| 175 | int fd, res; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 176 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 177 | if (openelf(path, &e, &fd) < 0) |
| 178 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 179 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 180 | res = listprobes(e, callback, path, payload); |
| 181 | elf_end(e); |
| 182 | close(fd); |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 183 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 184 | return res; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 185 | } |
| 186 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 187 | static int list_in_scn(Elf *e, Elf_Scn *section, size_t stridx, size_t symsize, |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 188 | struct bcc_symbol_option *option, |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 189 | bcc_elf_symcb callback, void *payload) { |
| 190 | Elf_Data *data = NULL; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 191 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 192 | while ((data = elf_getdata(section, data)) != 0) { |
| 193 | size_t i, symcount = data->d_size / symsize; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 194 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 195 | if (data->d_size % symsize) |
| 196 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 197 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 198 | for (i = 0; i < symcount; ++i) { |
| 199 | GElf_Sym sym; |
| 200 | const char *name; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 201 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 202 | if (!gelf_getsym(data, (int)i, &sym)) |
| 203 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 204 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 205 | if ((name = elf_strptr(e, stridx, sym.st_name)) == NULL) |
| 206 | continue; |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 207 | if (name[0] == 0) |
| 208 | continue; |
| 209 | |
| 210 | if (sym.st_value == 0) |
| 211 | continue; |
| 212 | |
Teng Qin | 91fc721 | 2017-09-13 17:21:13 -0700 | [diff] [blame] | 213 | uint32_t st_type = ELF_ST_TYPE(sym.st_info); |
Teng Qin | 91fc721 | 2017-09-13 17:21:13 -0700 | [diff] [blame] | 214 | if (!(option->use_symbol_type & (1 << st_type))) |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 215 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 216 | |
Teng Qin | cf13083 | 2017-05-10 12:51:17 -0700 | [diff] [blame] | 217 | if (callback(name, sym.st_value, sym.st_size, payload) < 0) |
Sasha Goldshtein | 07175d0 | 2016-10-06 01:11:55 +0300 | [diff] [blame] | 218 | return 1; // signal termination to caller |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 219 | } |
| 220 | } |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 221 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 222 | return 0; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 223 | } |
| 224 | |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 225 | static int listsymbols(Elf *e, bcc_elf_symcb callback, void *payload, |
| 226 | struct bcc_symbol_option *option) { |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 227 | Elf_Scn *section = NULL; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 228 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 229 | while ((section = elf_nextscn(e, section)) != 0) { |
| 230 | GElf_Shdr header; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 231 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 232 | if (!gelf_getshdr(section, &header)) |
| 233 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 234 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 235 | if (header.sh_type != SHT_SYMTAB && header.sh_type != SHT_DYNSYM) |
| 236 | continue; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 237 | |
Sasha Goldshtein | 07175d0 | 2016-10-06 01:11:55 +0300 | [diff] [blame] | 238 | int rc = list_in_scn(e, section, header.sh_link, header.sh_entsize, |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 239 | option, callback, payload); |
Sasha Goldshtein | 07175d0 | 2016-10-06 01:11:55 +0300 | [diff] [blame] | 240 | if (rc == 1) |
| 241 | break; // callback signaled termination |
| 242 | |
| 243 | if (rc < 0) |
| 244 | return rc; |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 245 | } |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 246 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 247 | return 0; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 248 | } |
| 249 | |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 250 | static Elf_Data * get_section_elf_data(Elf *e, const char *section_name) { |
| 251 | Elf_Scn *section = NULL; |
| 252 | GElf_Shdr header; |
| 253 | char *name; |
| 254 | |
| 255 | size_t stridx; |
| 256 | if (elf_getshdrstrndx(e, &stridx) != 0) |
| 257 | return NULL; |
| 258 | |
| 259 | while ((section = elf_nextscn(e, section)) != 0) { |
| 260 | if (!gelf_getshdr(section, &header)) |
| 261 | continue; |
| 262 | |
| 263 | name = elf_strptr(e, stridx, header.sh_name); |
| 264 | if (name && !strcmp(name, section_name)) { |
| 265 | return elf_getdata(section, NULL); |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | return NULL; |
| 270 | } |
| 271 | |
| 272 | static int find_debuglink(Elf *e, char **debug_file, unsigned int *crc) { |
| 273 | Elf_Data *data = NULL; |
| 274 | |
| 275 | *debug_file = NULL; |
| 276 | *crc = 0; |
| 277 | |
| 278 | data = get_section_elf_data(e, ".gnu_debuglink"); |
| 279 | if (!data || data->d_size <= 5) |
| 280 | return 0; |
| 281 | |
| 282 | *debug_file = (char *)data->d_buf; |
| 283 | *crc = *(unsigned int*)((char *)data->d_buf + data->d_size - 4); |
| 284 | |
| 285 | return *debug_file ? 1 : 0; |
| 286 | } |
| 287 | |
| 288 | static int find_buildid(Elf *e, char *buildid) { |
| 289 | Elf_Data *data = get_section_elf_data(e, ".note.gnu.build-id"); |
Sasha Goldshtein | e5d33df | 2017-02-11 19:35:14 -0500 | [diff] [blame] | 290 | if (!data || data->d_size <= 16 || strcmp((char *)data->d_buf + 12, "GNU")) |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 291 | return 0; |
| 292 | |
| 293 | char *buf = (char *)data->d_buf + 16; |
| 294 | size_t length = data->d_size - 16; |
Mark Drayton | f498e59 | 2017-02-21 22:25:57 +0000 | [diff] [blame] | 295 | size_t i = 0; |
| 296 | for (i = 0; i < length; ++i) { |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 297 | sprintf(buildid + (i * 2), "%02hhx", buf[i]); |
| 298 | } |
| 299 | |
| 300 | return 1; |
| 301 | } |
| 302 | |
| 303 | // The CRC algorithm used by GNU debuglink. Taken from: |
| 304 | // https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html |
| 305 | static unsigned int gnu_debuglink_crc32(unsigned int crc, |
| 306 | char *buf, size_t len) { |
| 307 | static const unsigned int crc32_table[256] = |
| 308 | { |
| 309 | 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, |
| 310 | 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, |
| 311 | 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, |
| 312 | 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, |
| 313 | 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, |
| 314 | 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, |
| 315 | 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, |
| 316 | 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, |
| 317 | 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, |
| 318 | 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, |
| 319 | 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, |
| 320 | 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, |
| 321 | 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, |
| 322 | 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, |
| 323 | 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, |
| 324 | 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, |
| 325 | 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, |
| 326 | 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, |
| 327 | 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, |
| 328 | 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, |
| 329 | 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, |
| 330 | 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, |
| 331 | 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, |
| 332 | 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, |
| 333 | 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, |
| 334 | 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, |
| 335 | 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, |
| 336 | 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, |
| 337 | 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, |
| 338 | 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, |
| 339 | 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, |
| 340 | 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, |
| 341 | 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, |
| 342 | 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, |
| 343 | 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, |
| 344 | 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, |
| 345 | 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, |
| 346 | 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, |
| 347 | 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, |
| 348 | 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, |
| 349 | 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, |
| 350 | 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, |
| 351 | 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, |
| 352 | 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, |
| 353 | 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, |
| 354 | 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, |
| 355 | 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, |
| 356 | 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, |
| 357 | 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, |
| 358 | 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, |
| 359 | 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, |
| 360 | 0x2d02ef8d |
| 361 | }; |
| 362 | char *end; |
| 363 | |
| 364 | crc = ~crc & 0xffffffff; |
| 365 | for (end = buf + len; buf < end; ++buf) |
| 366 | crc = crc32_table[(crc ^ *buf) & 0xff] ^ (crc >> 8); |
| 367 | return ~crc & 0xffffffff; |
| 368 | } |
| 369 | |
| 370 | static int verify_checksum(const char *file, unsigned int crc) { |
| 371 | struct stat st; |
| 372 | int fd; |
| 373 | void *buf; |
| 374 | unsigned int actual; |
| 375 | |
| 376 | fd = open(file, O_RDONLY); |
| 377 | if (fd < 0) |
| 378 | return 0; |
| 379 | |
jeromemarchand | b84714a | 2018-08-08 18:09:44 +0200 | [diff] [blame^] | 380 | if (fstat(fd, &st) < 0) { |
| 381 | close(fd); |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 382 | return 0; |
jeromemarchand | b84714a | 2018-08-08 18:09:44 +0200 | [diff] [blame^] | 383 | } |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 384 | |
| 385 | buf = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); |
| 386 | if (!buf) { |
| 387 | close(fd); |
| 388 | return 0; |
| 389 | } |
| 390 | |
| 391 | actual = gnu_debuglink_crc32(0, buf, st.st_size); |
| 392 | |
| 393 | munmap(buf, st.st_size); |
| 394 | close(fd); |
| 395 | return actual == crc; |
| 396 | } |
| 397 | |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 398 | static char *find_debug_via_debuglink(Elf *e, const char *binpath, |
| 399 | int check_crc) { |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 400 | char fullpath[PATH_MAX]; |
| 401 | char *bindir = NULL; |
| 402 | char *res = NULL; |
| 403 | unsigned int crc; |
| 404 | char *name; // the name of the debuginfo file |
| 405 | |
| 406 | if (!find_debuglink(e, &name, &crc)) |
| 407 | return NULL; |
| 408 | |
| 409 | bindir = strdup(binpath); |
| 410 | bindir = dirname(bindir); |
| 411 | |
Sasha Goldshtein | a359a90 | 2017-04-13 19:14:00 +0300 | [diff] [blame] | 412 | // Search for the file in 'binpath', but ignore the file we find if it |
| 413 | // matches the binary itself: the binary will always be probed later on, |
| 414 | // and it might contain poorer symbols (e.g. stripped or partial symbols) |
| 415 | // than the external debuginfo that might be available elsewhere. |
Nan Xiao | 0379779 | 2017-07-29 10:47:24 +0800 | [diff] [blame] | 416 | snprintf(fullpath, sizeof(fullpath),"%s/%s", bindir, name); |
Sasha Goldshtein | a359a90 | 2017-04-13 19:14:00 +0300 | [diff] [blame] | 417 | if (strcmp(fullpath, binpath) != 0 && access(fullpath, F_OK) != -1) { |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 418 | res = strdup(fullpath); |
| 419 | goto DONE; |
| 420 | } |
| 421 | |
| 422 | // Search for the file in 'binpath'/.debug |
Nan Xiao | 0379779 | 2017-07-29 10:47:24 +0800 | [diff] [blame] | 423 | snprintf(fullpath, sizeof(fullpath), "%s/.debug/%s", bindir, name); |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 424 | if (access(fullpath, F_OK) != -1) { |
| 425 | res = strdup(fullpath); |
| 426 | goto DONE; |
| 427 | } |
| 428 | |
| 429 | // Search for the file in the global debug directory /usr/lib/debug/'binpath' |
Nan Xiao | 0379779 | 2017-07-29 10:47:24 +0800 | [diff] [blame] | 430 | snprintf(fullpath, sizeof(fullpath), "/usr/lib/debug%s/%s", bindir, name); |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 431 | if (access(fullpath, F_OK) != -1) { |
| 432 | res = strdup(fullpath); |
| 433 | goto DONE; |
| 434 | } |
| 435 | |
| 436 | DONE: |
| 437 | free(bindir); |
jeromemarchand | b84714a | 2018-08-08 18:09:44 +0200 | [diff] [blame^] | 438 | if (res && check_crc && !verify_checksum(res, crc)) |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 439 | return NULL; |
| 440 | return res; |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 441 | } |
| 442 | |
| 443 | static char *find_debug_via_buildid(Elf *e) { |
| 444 | char fullpath[PATH_MAX]; |
| 445 | char buildid[128]; // currently 40 seems to be default, let's be safe |
| 446 | |
| 447 | if (!find_buildid(e, buildid)) |
| 448 | return NULL; |
| 449 | |
| 450 | // Search for the file in the global debug directory with a sub-path: |
| 451 | // mm/nnnnnn...nnnn.debug |
| 452 | // Where mm are the first two characters of the buildid, and nnnn are the |
| 453 | // rest of the build id, followed by .debug. |
Nan Xiao | 0379779 | 2017-07-29 10:47:24 +0800 | [diff] [blame] | 454 | snprintf(fullpath, sizeof(fullpath), "/usr/lib/debug/.build-id/%c%c/%s.debug", |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 455 | buildid[0], buildid[1], buildid + 2); |
| 456 | if (access(fullpath, F_OK) != -1) { |
| 457 | return strdup(fullpath); |
| 458 | } |
| 459 | |
| 460 | return NULL; |
| 461 | } |
| 462 | |
| 463 | static int foreach_sym_core(const char *path, bcc_elf_symcb callback, |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 464 | struct bcc_symbol_option *option, void *payload, |
| 465 | int is_debug_file) { |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 466 | Elf *e; |
| 467 | int fd, res; |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 468 | char *debug_file; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 469 | |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 470 | if (!option) |
| 471 | return -1; |
| 472 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 473 | if (openelf(path, &e, &fd) < 0) |
| 474 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 475 | |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 476 | // If there is a separate debuginfo file, try to locate and read it, first |
| 477 | // using the build-id section, then using the debuglink section. These are |
| 478 | // also the rules that GDB folows. |
| 479 | // See: https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 480 | if (option->use_debug_file && !is_debug_file) { |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 481 | // The is_debug_file argument helps avoid infinitely resolving debuginfo |
| 482 | // files for debuginfo files and so on. |
| 483 | debug_file = find_debug_via_buildid(e); |
| 484 | if (!debug_file) |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 485 | debug_file = find_debug_via_debuglink(e, path, |
| 486 | option->check_debug_file_crc); |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 487 | if (debug_file) { |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 488 | foreach_sym_core(debug_file, callback, option, payload, 1); |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 489 | free(debug_file); |
| 490 | } |
| 491 | } |
| 492 | |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 493 | res = listsymbols(e, callback, payload, option); |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 494 | elf_end(e); |
| 495 | close(fd); |
| 496 | return res; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 497 | } |
| 498 | |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 499 | int bcc_elf_foreach_sym(const char *path, bcc_elf_symcb callback, |
Teng Qin | 0336a29 | 2017-05-04 00:09:20 -0700 | [diff] [blame] | 500 | void *option, void *payload) { |
| 501 | return foreach_sym_core( |
| 502 | path, callback, (struct bcc_symbol_option*)option, payload, 0); |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 503 | } |
| 504 | |
Joel Fernandes | 5a1106c | 2018-04-07 10:43:15 +0000 | [diff] [blame] | 505 | int bcc_elf_get_text_scn_info(const char *path, uint64_t *addr, |
| 506 | uint64_t *offset) { |
| 507 | Elf *e = NULL; |
| 508 | int fd = -1, err; |
| 509 | Elf_Scn *section = NULL; |
| 510 | GElf_Shdr header; |
| 511 | size_t stridx; |
| 512 | char *name; |
| 513 | |
| 514 | if ((err = openelf(path, &e, &fd)) < 0 || |
| 515 | (err = elf_getshdrstrndx(e, &stridx)) < 0) |
| 516 | goto exit; |
| 517 | |
| 518 | err = -1; |
| 519 | while ((section = elf_nextscn(e, section)) != 0) { |
| 520 | if (!gelf_getshdr(section, &header)) |
| 521 | continue; |
| 522 | |
| 523 | name = elf_strptr(e, stridx, header.sh_name); |
| 524 | if (name && !strcmp(name, ".text")) { |
| 525 | *addr = (uint64_t)header.sh_addr; |
| 526 | *offset = (uint64_t)header.sh_offset; |
| 527 | err = 0; |
| 528 | break; |
| 529 | } |
| 530 | } |
| 531 | |
| 532 | exit: |
| 533 | if (e) |
| 534 | elf_end(e); |
| 535 | if (fd >= 0) |
| 536 | close(fd); |
| 537 | return err; |
| 538 | } |
| 539 | |
Teng Qin | a8f6db9 | 2017-09-20 16:06:38 -0700 | [diff] [blame] | 540 | int bcc_elf_foreach_load_section(const char *path, |
| 541 | bcc_elf_load_sectioncb callback, |
| 542 | void *payload) { |
| 543 | Elf *e = NULL; |
| 544 | int fd = -1, err = -1, res; |
| 545 | size_t nhdrs, i; |
| 546 | |
| 547 | if (openelf(path, &e, &fd) < 0) |
| 548 | goto exit; |
| 549 | |
| 550 | if (elf_getphdrnum(e, &nhdrs) != 0) |
| 551 | goto exit; |
| 552 | |
| 553 | GElf_Phdr header; |
| 554 | for (i = 0; i < nhdrs; i++) { |
| 555 | if (!gelf_getphdr(e, (int)i, &header)) |
| 556 | continue; |
| 557 | if (header.p_type != PT_LOAD || !(header.p_flags & PF_X)) |
| 558 | continue; |
| 559 | res = callback(header.p_vaddr, header.p_memsz, header.p_offset, payload); |
| 560 | if (res < 0) { |
| 561 | err = 1; |
| 562 | goto exit; |
| 563 | } |
| 564 | } |
| 565 | err = 0; |
| 566 | |
| 567 | exit: |
| 568 | if (e) |
| 569 | elf_end(e); |
| 570 | if (fd >= 0) |
| 571 | close(fd); |
| 572 | return err; |
| 573 | } |
| 574 | |
Teng Qin | d82e813 | 2017-05-04 12:09:14 -0700 | [diff] [blame] | 575 | int bcc_elf_get_type(const char *path) { |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 576 | Elf *e; |
| 577 | GElf_Ehdr hdr; |
Teng Qin | d82e813 | 2017-05-04 12:09:14 -0700 | [diff] [blame] | 578 | int fd; |
| 579 | void* res = NULL; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 580 | |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 581 | if (openelf(path, &e, &fd) < 0) |
| 582 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 583 | |
Teng Qin | d82e813 | 2017-05-04 12:09:14 -0700 | [diff] [blame] | 584 | res = (void*)gelf_getehdr(e, &hdr); |
Vicent Marti | c1c2373 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 585 | elf_end(e); |
| 586 | close(fd); |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 587 | |
Teng Qin | d82e813 | 2017-05-04 12:09:14 -0700 | [diff] [blame] | 588 | if (!res) |
| 589 | return -1; |
| 590 | else |
| 591 | return hdr.e_type; |
| 592 | } |
| 593 | |
| 594 | int bcc_elf_is_exe(const char *path) { |
| 595 | return (bcc_elf_get_type(path) != -1) && (access(path, X_OK) == 0); |
| 596 | } |
| 597 | |
| 598 | int bcc_elf_is_shared_obj(const char *path) { |
| 599 | return bcc_elf_get_type(path) == ET_DYN; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 600 | } |
| 601 | |
Teng Qin | 1670d33 | 2017-10-06 18:08:33 -0700 | [diff] [blame] | 602 | int bcc_elf_is_vdso(const char *name) { |
| 603 | return strcmp(name, "[vdso]") == 0; |
| 604 | } |
| 605 | |
| 606 | // -2: Failed |
| 607 | // -1: Not initialized |
| 608 | // >0: Initialized |
| 609 | static int vdso_image_fd = -1; |
| 610 | |
| 611 | static int find_vdso(const char *name, uint64_t st, uint64_t en, |
| 612 | uint64_t offset, bool enter_ns, void *payload) { |
| 613 | int fd; |
| 614 | char tmpfile[128]; |
| 615 | if (!bcc_elf_is_vdso(name)) |
| 616 | return 0; |
| 617 | |
| 618 | void *image = malloc(en - st); |
| 619 | if (!image) |
| 620 | goto on_error; |
| 621 | memcpy(image, (void *)st, en - st); |
| 622 | |
| 623 | snprintf(tmpfile, sizeof(tmpfile), "/tmp/bcc_%d_vdso_image_XXXXXX", getpid()); |
| 624 | fd = mkostemp(tmpfile, O_CLOEXEC); |
| 625 | if (fd < 0) { |
| 626 | fprintf(stderr, "Unable to create temp file: %s\n", strerror(errno)); |
| 627 | goto on_error; |
| 628 | } |
| 629 | // Unlink the file to avoid leaking |
| 630 | if (unlink(tmpfile) == -1) |
| 631 | fprintf(stderr, "Unlink %s failed: %s\n", tmpfile, strerror(errno)); |
| 632 | |
| 633 | if (write(fd, image, en - st) == -1) { |
| 634 | fprintf(stderr, "Failed to write to vDSO image: %s\n", strerror(errno)); |
| 635 | close(fd); |
| 636 | goto on_error; |
| 637 | } |
| 638 | vdso_image_fd = fd; |
| 639 | |
| 640 | on_error: |
| 641 | if (image) |
| 642 | free(image); |
| 643 | // Always stop the iteration |
| 644 | return -1; |
| 645 | } |
| 646 | |
| 647 | int bcc_elf_foreach_vdso_sym(bcc_elf_symcb callback, void *payload) { |
| 648 | Elf *elf; |
| 649 | static struct bcc_symbol_option default_option = { |
| 650 | .use_debug_file = 0, |
| 651 | .check_debug_file_crc = 0, |
| 652 | .use_symbol_type = (1 << STT_FUNC) | (1 << STT_GNU_IFUNC) |
| 653 | }; |
| 654 | |
| 655 | if (vdso_image_fd == -1) { |
| 656 | vdso_image_fd = -2; |
| 657 | bcc_procutils_each_module(getpid(), &find_vdso, NULL); |
| 658 | } |
| 659 | if (vdso_image_fd == -2) |
| 660 | return -1; |
| 661 | |
| 662 | if (openelf_fd(vdso_image_fd, &elf) == -1) |
| 663 | return -1; |
| 664 | |
| 665 | return listsymbols(elf, callback, payload, &default_option); |
| 666 | } |
| 667 | |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 668 | #if 0 |
| 669 | #include <stdio.h> |
| 670 | |
| 671 | int main(int argc, char *argv[]) |
| 672 | { |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 673 | uint64_t addr; |
| 674 | if (bcc_elf_findsym(argv[1], argv[2], -1, STT_FUNC, &addr) < 0) |
| 675 | return -1; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 676 | |
Sasha Goldshtein | 0155385 | 2017-02-09 03:58:09 -0500 | [diff] [blame] | 677 | printf("%s: %p\n", argv[2], (void *)addr); |
| 678 | return 0; |
Vicent Marti | b8f0f09 | 2016-04-20 13:24:54 +0200 | [diff] [blame] | 679 | } |
| 680 | #endif |