diff options
Diffstat (limited to 'tools/bpf/resolve_btfids/main.c')
| -rw-r--r-- | tools/bpf/resolve_btfids/main.c | 65 |
1 files changed, 63 insertions, 2 deletions
diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c index 4d9ecb975862..dfa540d8a02d 100644 --- a/tools/bpf/resolve_btfids/main.c +++ b/tools/bpf/resolve_btfids/main.c @@ -199,9 +199,16 @@ static char *get_id(const char *prefix_end) /* * __BTF_ID__func__vfs_truncate__0 * prefix_end = ^ + * pos = ^ */ - char *p, *id = strdup(prefix_end + sizeof("__") - 1); + int len = strlen(prefix_end); + int pos = sizeof("__") - 1; + char *p, *id; + if (pos >= len) + return NULL; + + id = strdup(prefix_end + pos); if (id) { /* * __BTF_ID__func__vfs_truncate__0 @@ -220,6 +227,24 @@ static char *get_id(const char *prefix_end) return id; } +static struct btf_id *add_set(struct object *obj, char *name) +{ + /* + * __BTF_ID__set__name + * name = ^ + * id = ^ + */ + char *id = name + sizeof(BTF_SET "__") - 1; + int len = strlen(name); + + if (id >= name + len) { + pr_err("FAILED to parse set name: %s\n", name); + return NULL; + } + + return btf_id__add(&obj->sets, id, true); +} + static struct btf_id *add_symbol(struct rb_root *root, char *name, size_t size) { char *id; @@ -233,6 +258,39 @@ static struct btf_id *add_symbol(struct rb_root *root, char *name, size_t size) return btf_id__add(root, id, false); } +/* + * The data of compressed section should be aligned to 4 + * (for 32bit) or 8 (for 64 bit) bytes. The binutils ld + * sets sh_addralign to 1, which makes libelf fail with + * misaligned section error during the update: + * FAILED elf_update(WRITE): invalid section alignment + * + * While waiting for ld fix, we fix the compressed sections + * sh_addralign value manualy. + */ +static int compressed_section_fix(Elf *elf, Elf_Scn *scn, GElf_Shdr *sh) +{ + int expected = gelf_getclass(elf) == ELFCLASS32 ? 4 : 8; + + if (!(sh->sh_flags & SHF_COMPRESSED)) + return 0; + + if (sh->sh_addralign == expected) + return 0; + + pr_debug2(" - fixing wrong alignment sh_addralign %u, expected %u\n", + sh->sh_addralign, expected); + + sh->sh_addralign = expected; + + if (gelf_update_shdr(scn, sh) == 0) { + printf("FAILED cannot update section header: %s\n", + elf_errmsg(-1)); + return -1; + } + return 0; +} + static int elf_collect(struct object *obj) { Elf_Scn *scn = NULL; @@ -309,6 +367,9 @@ static int elf_collect(struct object *obj) obj->efile.idlist_shndx = idx; obj->efile.idlist_addr = sh.sh_addr; } + + if (compressed_section_fix(elf, scn, &sh)) + return -1; } return 0; @@ -376,7 +437,7 @@ static int symbols_collect(struct object *obj) id = add_symbol(&obj->funcs, prefix, sizeof(BTF_FUNC) - 1); /* set */ } else if (!strncmp(prefix, BTF_SET, sizeof(BTF_SET) - 1)) { - id = add_symbol(&obj->sets, prefix, sizeof(BTF_SET) - 1); + id = add_set(obj, prefix); /* * SET objects store list's count, which is encoded * in symbol's size, together with 'cnt' field hence |