diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/perf/util/symbol-elf.c | 1226 |
1 files changed, 920 insertions, 306 deletions
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 44dd86a4f25f..6d2c280a1730 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -7,13 +7,12 @@ #include <unistd.h> #include <inttypes.h> +#include "compress.h" #include "dso.h" #include "map.h" #include "maps.h" #include "symbol.h" #include "symsrc.h" -#include "demangle-java.h" -#include "demangle-rust.h" #include "machine.h" #include "vdso.h" #include "debug.h" @@ -21,13 +20,30 @@ #include <linux/ctype.h> #include <linux/kernel.h> #include <linux/zalloc.h> +#include <linux/string.h> #include <symbol/kallsyms.h> #include <internal/lib.h> +#ifdef HAVE_LIBBFD_SUPPORT +#define PACKAGE 'perf' +#include <bfd.h> +#endif + +#if defined(HAVE_LIBBFD_SUPPORT) || defined(HAVE_CPLUS_DEMANGLE_SUPPORT) +#ifndef DMGL_PARAMS +#define DMGL_PARAMS (1 << 0) /* Include function args */ +#define DMGL_ANSI (1 << 1) /* Include const, volatile, etc */ +#endif +#endif + #ifndef EM_AARCH64 #define EM_AARCH64 183 /* ARM 64 bit */ #endif +#ifndef EM_LOONGARCH +#define EM_LOONGARCH 258 +#endif + #ifndef ELF32_ST_VISIBILITY #define ELF32_ST_VISIBILITY(o) ((o) & 0x03) #endif @@ -44,34 +60,6 @@ typedef Elf64_Nhdr GElf_Nhdr; -#ifndef DMGL_PARAMS -#define DMGL_NO_OPTS 0 /* For readability... */ -#define DMGL_PARAMS (1 << 0) /* Include function args */ -#define DMGL_ANSI (1 << 1) /* Include const, volatile, etc */ -#endif - -#ifdef HAVE_LIBBFD_SUPPORT -#define PACKAGE 'perf' -#include <bfd.h> -#else -#ifdef HAVE_CPLUS_DEMANGLE_SUPPORT -extern char *cplus_demangle(const char *, int); - -static inline char *bfd_demangle(void __maybe_unused *v, const char *c, int i) -{ - return cplus_demangle(c, i); -} -#else -#ifdef NO_DEMANGLE -static inline char *bfd_demangle(void __maybe_unused *v, - const char __maybe_unused *c, - int __maybe_unused i) -{ - return NULL; -} -#endif -#endif -#endif #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT static int elf_getphdrnum(Elf *elf, size_t *dst) @@ -183,7 +171,7 @@ static inline bool elf_sec__is_data(const GElf_Shdr *shdr, static bool elf_sec__filter(GElf_Shdr *shdr, Elf_Data *secstrs) { - return elf_sec__is_text(shdr, secstrs) || + return elf_sec__is_text(shdr, secstrs) || elf_sec__is_data(shdr, secstrs); } @@ -212,7 +200,7 @@ Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, Elf_Scn *sec = NULL; size_t cnt = 1; - /* Elf is corrupted/truncated, avoid calling elf_strptr. */ + /* ELF is corrupted/truncated, avoid calling elf_strptr. */ if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) return NULL; @@ -232,46 +220,390 @@ Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, return NULL; } -static bool want_demangle(bool is_kernel_sym) +bool filename__has_section(const char *filename, const char *sec) { - return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle; + int fd; + Elf *elf; + GElf_Ehdr ehdr; + GElf_Shdr shdr; + bool found = false; + + fd = open(filename, O_RDONLY); + if (fd < 0) + return false; + + elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); + if (elf == NULL) + goto out; + + if (gelf_getehdr(elf, &ehdr) == NULL) + goto elf_out; + + found = !!elf_section_by_name(elf, &ehdr, &shdr, sec, NULL); + +elf_out: + elf_end(elf); +out: + close(fd); + return found; } -static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name) +static int elf_read_program_header(Elf *elf, u64 vaddr, GElf_Phdr *phdr) { - int demangle_flags = verbose > 0 ? (DMGL_PARAMS | DMGL_ANSI) : DMGL_NO_OPTS; - char *demangled = NULL; + size_t i, phdrnum; + u64 sz; - /* - * We need to figure out if the object was created from C++ sources - * DWARF DW_compile_unit has this, but we don't always have access - * to it... - */ - if (!want_demangle(dso->kernel || kmodule)) - return demangled; + if (elf_getphdrnum(elf, &phdrnum)) + return -1; - demangled = bfd_demangle(NULL, elf_name, demangle_flags); - if (demangled == NULL) - demangled = java_demangle_sym(elf_name, JAVA_DEMANGLE_NORET); - else if (rust_is_mangled(demangled)) - /* - * Input to Rust demangling is the BFD-demangled - * name which it Rust-demangles in place. - */ - rust_demangle_sym(demangled); + for (i = 0; i < phdrnum; i++) { + if (gelf_getphdr(elf, i, phdr) == NULL) + return -1; + + if (phdr->p_type != PT_LOAD) + continue; + + sz = max(phdr->p_memsz, phdr->p_filesz); + if (!sz) + continue; + + if (vaddr >= phdr->p_vaddr && (vaddr < phdr->p_vaddr + sz)) + return 0; + } + + /* Not found any valid program header */ + return -1; +} + +struct rel_info { + u32 nr_entries; + u32 *sorted; + bool is_rela; + Elf_Data *reldata; + GElf_Rela rela; + GElf_Rel rel; +}; + +static u32 get_rel_symidx(struct rel_info *ri, u32 idx) +{ + idx = ri->sorted ? ri->sorted[idx] : idx; + if (ri->is_rela) { + gelf_getrela(ri->reldata, idx, &ri->rela); + return GELF_R_SYM(ri->rela.r_info); + } + gelf_getrel(ri->reldata, idx, &ri->rel); + return GELF_R_SYM(ri->rel.r_info); +} + +static u64 get_rel_offset(struct rel_info *ri, u32 x) +{ + if (ri->is_rela) { + GElf_Rela rela; + + gelf_getrela(ri->reldata, x, &rela); + return rela.r_offset; + } else { + GElf_Rel rel; + + gelf_getrel(ri->reldata, x, &rel); + return rel.r_offset; + } +} + +static int rel_cmp(const void *a, const void *b, void *r) +{ + struct rel_info *ri = r; + u64 a_offset = get_rel_offset(ri, *(const u32 *)a); + u64 b_offset = get_rel_offset(ri, *(const u32 *)b); + + return a_offset < b_offset ? -1 : (a_offset > b_offset ? 1 : 0); +} + +static int sort_rel(struct rel_info *ri) +{ + size_t sz = sizeof(ri->sorted[0]); + u32 i; + + ri->sorted = calloc(ri->nr_entries, sz); + if (!ri->sorted) + return -1; + for (i = 0; i < ri->nr_entries; i++) + ri->sorted[i] = i; + qsort_r(ri->sorted, ri->nr_entries, sz, rel_cmp, ri); + return 0; +} + +/* + * For x86_64, the GNU linker is putting IFUNC information in the relocation + * addend. + */ +static bool addend_may_be_ifunc(GElf_Ehdr *ehdr, struct rel_info *ri) +{ + return ehdr->e_machine == EM_X86_64 && ri->is_rela && + GELF_R_TYPE(ri->rela.r_info) == R_X86_64_IRELATIVE; +} + +static bool get_ifunc_name(Elf *elf, struct dso *dso, GElf_Ehdr *ehdr, + struct rel_info *ri, char *buf, size_t buf_sz) +{ + u64 addr = ri->rela.r_addend; + struct symbol *sym; + GElf_Phdr phdr; + + if (!addend_may_be_ifunc(ehdr, ri)) + return false; + + if (elf_read_program_header(elf, addr, &phdr)) + return false; + + addr -= phdr.p_vaddr - phdr.p_offset; + + sym = dso__find_symbol_nocache(dso, addr); + + /* Expecting the address to be an IFUNC or IFUNC alias */ + if (!sym || sym->start != addr || (sym->type != STT_GNU_IFUNC && !sym->ifunc_alias)) + return false; + + snprintf(buf, buf_sz, "%s@plt", sym->name); + + return true; +} + +static void exit_rel(struct rel_info *ri) +{ + zfree(&ri->sorted); +} + +static bool get_plt_sizes(struct dso *dso, GElf_Ehdr *ehdr, GElf_Shdr *shdr_plt, + u64 *plt_header_size, u64 *plt_entry_size) +{ + switch (ehdr->e_machine) { + case EM_ARM: + *plt_header_size = 20; + *plt_entry_size = 12; + return true; + case EM_AARCH64: + *plt_header_size = 32; + *plt_entry_size = 16; + return true; + case EM_LOONGARCH: + *plt_header_size = 32; + *plt_entry_size = 16; + return true; + case EM_SPARC: + *plt_header_size = 48; + *plt_entry_size = 12; + return true; + case EM_SPARCV9: + *plt_header_size = 128; + *plt_entry_size = 32; + return true; + case EM_386: + case EM_X86_64: + *plt_entry_size = shdr_plt->sh_entsize; + /* Size is 8 or 16, if not, assume alignment indicates size */ + if (*plt_entry_size != 8 && *plt_entry_size != 16) + *plt_entry_size = shdr_plt->sh_addralign == 8 ? 8 : 16; + *plt_header_size = *plt_entry_size; + break; + default: /* FIXME: s390/alpha/mips/parisc/poperpc/sh/xtensa need to be checked */ + *plt_header_size = shdr_plt->sh_entsize; + *plt_entry_size = shdr_plt->sh_entsize; + break; + } + if (*plt_entry_size) + return true; + pr_debug("Missing PLT entry size for %s\n", dso__long_name(dso)); + return false; +} + +static bool machine_is_x86(GElf_Half e_machine) +{ + return e_machine == EM_386 || e_machine == EM_X86_64; +} + +struct rela_dyn { + GElf_Addr offset; + u32 sym_idx; +}; + +struct rela_dyn_info { + struct dso *dso; + Elf_Data *plt_got_data; + u32 nr_entries; + struct rela_dyn *sorted; + Elf_Data *dynsym_data; + Elf_Data *dynstr_data; + Elf_Data *rela_dyn_data; +}; + +static void exit_rela_dyn(struct rela_dyn_info *di) +{ + zfree(&di->sorted); +} + +static int cmp_offset(const void *a, const void *b) +{ + const struct rela_dyn *va = a; + const struct rela_dyn *vb = b; + + return va->offset < vb->offset ? -1 : (va->offset > vb->offset ? 1 : 0); +} + +static int sort_rela_dyn(struct rela_dyn_info *di) +{ + u32 i, n; + + di->sorted = calloc(di->nr_entries, sizeof(di->sorted[0])); + if (!di->sorted) + return -1; + + /* Get data for sorting: the offset and symbol index */ + for (i = 0, n = 0; i < di->nr_entries; i++) { + GElf_Rela rela; + u32 sym_idx; + + gelf_getrela(di->rela_dyn_data, i, &rela); + sym_idx = GELF_R_SYM(rela.r_info); + if (sym_idx) { + di->sorted[n].sym_idx = sym_idx; + di->sorted[n].offset = rela.r_offset; + n += 1; + } + } + + /* Sort by offset */ + di->nr_entries = n; + qsort(di->sorted, n, sizeof(di->sorted[0]), cmp_offset); + + return 0; +} + +static void get_rela_dyn_info(Elf *elf, GElf_Ehdr *ehdr, struct rela_dyn_info *di, Elf_Scn *scn) +{ + GElf_Shdr rela_dyn_shdr; + GElf_Shdr shdr; - return demangled; + di->plt_got_data = elf_getdata(scn, NULL); + + scn = elf_section_by_name(elf, ehdr, &rela_dyn_shdr, ".rela.dyn", NULL); + if (!scn || !rela_dyn_shdr.sh_link || !rela_dyn_shdr.sh_entsize) + return; + + di->nr_entries = rela_dyn_shdr.sh_size / rela_dyn_shdr.sh_entsize; + di->rela_dyn_data = elf_getdata(scn, NULL); + + scn = elf_getscn(elf, rela_dyn_shdr.sh_link); + if (!scn || !gelf_getshdr(scn, &shdr) || !shdr.sh_link) + return; + + di->dynsym_data = elf_getdata(scn, NULL); + di->dynstr_data = elf_getdata(elf_getscn(elf, shdr.sh_link), NULL); + + if (!di->plt_got_data || !di->dynstr_data || !di->dynsym_data || !di->rela_dyn_data) + return; + + /* Sort into offset order */ + sort_rela_dyn(di); +} + +/* Get instruction displacement from a plt entry for x86_64 */ +static u32 get_x86_64_plt_disp(const u8 *p) +{ + u8 endbr64[] = {0xf3, 0x0f, 0x1e, 0xfa}; + int n = 0; + + /* Skip endbr64 */ + if (!memcmp(p, endbr64, sizeof(endbr64))) + n += sizeof(endbr64); + /* Skip bnd prefix */ + if (p[n] == 0xf2) + n += 1; + /* jmp with 4-byte displacement */ + if (p[n] == 0xff && p[n + 1] == 0x25) { + u32 disp; + + n += 2; + /* Also add offset from start of entry to end of instruction */ + memcpy(&disp, p + n, sizeof(disp)); + return n + 4 + le32toh(disp); + } + return 0; } -#define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \ - for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \ - idx < nr_entries; \ - ++idx, pos = gelf_getrel(reldata, idx, &pos_mem)) +static bool get_plt_got_name(GElf_Shdr *shdr, size_t i, + struct rela_dyn_info *di, + char *buf, size_t buf_sz) +{ + struct rela_dyn vi, *vr; + const char *sym_name; + char *demangled; + GElf_Sym sym; + bool result; + u32 disp; + + if (!di->sorted) + return false; + + disp = get_x86_64_plt_disp(di->plt_got_data->d_buf + i); + if (!disp) + return false; -#define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \ - for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \ - idx < nr_entries; \ - ++idx, pos = gelf_getrela(reldata, idx, &pos_mem)) + /* Compute target offset of the .plt.got entry */ + vi.offset = shdr->sh_offset + di->plt_got_data->d_off + i + disp; + + /* Find that offset in .rela.dyn (sorted by offset) */ + vr = bsearch(&vi, di->sorted, di->nr_entries, sizeof(di->sorted[0]), cmp_offset); + if (!vr) + return false; + + /* Get the associated symbol */ + gelf_getsym(di->dynsym_data, vr->sym_idx, &sym); + sym_name = elf_sym__name(&sym, di->dynstr_data); + demangled = dso__demangle_sym(di->dso, /*kmodule=*/0, sym_name); + if (demangled != NULL) + sym_name = demangled; + + snprintf(buf, buf_sz, "%s@plt", sym_name); + + result = *sym_name; + + free(demangled); + + return result; +} + +static int dso__synthesize_plt_got_symbols(struct dso *dso, Elf *elf, + GElf_Ehdr *ehdr, + char *buf, size_t buf_sz) +{ + struct rela_dyn_info di = { .dso = dso }; + struct symbol *sym; + GElf_Shdr shdr; + Elf_Scn *scn; + int err = -1; + size_t i; + + scn = elf_section_by_name(elf, ehdr, &shdr, ".plt.got", NULL); + if (!scn || !shdr.sh_entsize) + return 0; + + if (ehdr->e_machine == EM_X86_64) + get_rela_dyn_info(elf, ehdr, &di, scn); + + for (i = 0; i < shdr.sh_size; i += shdr.sh_entsize) { + if (!get_plt_got_name(&shdr, i, &di, buf, buf_sz)) + snprintf(buf, buf_sz, "offset_%#" PRIx64 "@plt", (u64)shdr.sh_offset + i); + sym = symbol__new(shdr.sh_offset + i, shdr.sh_entsize, STB_GLOBAL, STT_FUNC, buf); + if (!sym) + goto out; + symbols__insert(dso__symbols(dso), sym); + } + err = 0; +out: + exit_rela_dyn(&di); + return err; +} /* * We need to check if we have a .dynsym, so that we can handle the @@ -282,56 +614,104 @@ static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name) */ int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss) { - uint32_t nr_rel_entries, idx; + uint32_t idx; GElf_Sym sym; u64 plt_offset, plt_header_size, plt_entry_size; - GElf_Shdr shdr_plt; - struct symbol *f; + GElf_Shdr shdr_plt, plt_sec_shdr; + struct symbol *f, *plt_sym; GElf_Shdr shdr_rel_plt, shdr_dynsym; - Elf_Data *reldata, *syms, *symstrs; + Elf_Data *syms, *symstrs; Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym; - size_t dynsym_idx; GElf_Ehdr ehdr; char sympltname[1024]; Elf *elf; - int nr = 0, symidx, err = 0; - - if (!ss->dynsym) - return 0; + int nr = 0, err = -1; + struct rel_info ri = { .is_rela = false }; + bool lazy_plt; elf = ss->elf; ehdr = ss->ehdr; - scn_dynsym = ss->dynsym; - shdr_dynsym = ss->dynshdr; - dynsym_idx = ss->dynsym_idx; + if (!elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL)) + return 0; + + /* + * A symbol from a previous section (e.g. .init) can have been expanded + * by symbols__fixup_end() to overlap .plt. Truncate it before adding + * a symbol for .plt header. + */ + f = dso__find_symbol_nocache(dso, shdr_plt.sh_offset); + if (f && f->start < shdr_plt.sh_offset && f->end > shdr_plt.sh_offset) + f->end = shdr_plt.sh_offset; + + if (!get_plt_sizes(dso, &ehdr, &shdr_plt, &plt_header_size, &plt_entry_size)) + return 0; + + /* Add a symbol for .plt header */ + plt_sym = symbol__new(shdr_plt.sh_offset, plt_header_size, STB_GLOBAL, STT_FUNC, ".plt"); + if (!plt_sym) + goto out_elf_end; + symbols__insert(dso__symbols(dso), plt_sym); - if (scn_dynsym == NULL) + /* Only x86 has .plt.got */ + if (machine_is_x86(ehdr.e_machine) && + dso__synthesize_plt_got_symbols(dso, elf, &ehdr, sympltname, sizeof(sympltname))) goto out_elf_end; + /* Only x86 has .plt.sec */ + if (machine_is_x86(ehdr.e_machine) && + elf_section_by_name(elf, &ehdr, &plt_sec_shdr, ".plt.sec", NULL)) { + if (!get_plt_sizes(dso, &ehdr, &plt_sec_shdr, &plt_header_size, &plt_entry_size)) + return 0; + /* Extend .plt symbol to entire .plt */ + plt_sym->end = plt_sym->start + shdr_plt.sh_size; + /* Use .plt.sec offset */ + plt_offset = plt_sec_shdr.sh_offset; + lazy_plt = false; + } else { + plt_offset = shdr_plt.sh_offset; + lazy_plt = true; + } + scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, ".rela.plt", NULL); if (scn_plt_rel == NULL) { scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, ".rel.plt", NULL); if (scn_plt_rel == NULL) - goto out_elf_end; + return 0; } - err = -1; + if (shdr_rel_plt.sh_type != SHT_RELA && + shdr_rel_plt.sh_type != SHT_REL) + return 0; - if (shdr_rel_plt.sh_link != dynsym_idx) - goto out_elf_end; + if (!shdr_rel_plt.sh_link) + return 0; - if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL) + if (shdr_rel_plt.sh_link == ss->dynsym_idx) { + scn_dynsym = ss->dynsym; + shdr_dynsym = ss->dynshdr; + } else if (shdr_rel_plt.sh_link == ss->symtab_idx) { + /* + * A static executable can have a .plt due to IFUNCs, in which + * case .symtab is used not .dynsym. + */ + scn_dynsym = ss->symtab; + shdr_dynsym = ss->symshdr; + } else { goto out_elf_end; + } + + if (!scn_dynsym) + return 0; /* * Fetch the relocation section to find the idxes to the GOT * and the symbols in the .dynsym they refer to. */ - reldata = elf_getdata(scn_plt_rel, NULL); - if (reldata == NULL) + ri.reldata = elf_getdata(scn_plt_rel, NULL); + if (!ri.reldata) goto out_elf_end; syms = elf_getdata(scn_dynsym, NULL); @@ -349,105 +729,64 @@ int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss) if (symstrs->d_size == 0) goto out_elf_end; - nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize; - plt_offset = shdr_plt.sh_offset; - switch (ehdr.e_machine) { - case EM_ARM: - plt_header_size = 20; - plt_entry_size = 12; - break; - - case EM_AARCH64: - plt_header_size = 32; - plt_entry_size = 16; - break; + ri.nr_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize; - case EM_SPARC: - plt_header_size = 48; - plt_entry_size = 12; - break; - - case EM_SPARCV9: - plt_header_size = 128; - plt_entry_size = 32; - break; + ri.is_rela = shdr_rel_plt.sh_type == SHT_RELA; - default: /* FIXME: s390/alpha/mips/parisc/poperpc/sh/xtensa need to be checked */ - plt_header_size = shdr_plt.sh_entsize; - plt_entry_size = shdr_plt.sh_entsize; - break; + if (lazy_plt) { + /* + * Assume a .plt with the same number of entries as the number + * of relocation entries is not lazy and does not have a header. + */ + if (ri.nr_entries * plt_entry_size == shdr_plt.sh_size) + dso__delete_symbol(dso, plt_sym); + else + plt_offset += plt_header_size; } - plt_offset += plt_header_size; - if (shdr_rel_plt.sh_type == SHT_RELA) { - GElf_Rela pos_mem, *pos; - - elf_section__for_each_rela(reldata, pos, pos_mem, idx, - nr_rel_entries) { - const char *elf_name = NULL; - char *demangled = NULL; - symidx = GELF_R_SYM(pos->r_info); - gelf_getsym(syms, symidx, &sym); + /* + * x86 doesn't insert IFUNC relocations in .plt order, so sort to get + * back in order. + */ + if (machine_is_x86(ehdr.e_machine) && sort_rel(&ri)) + goto out_elf_end; - elf_name = elf_sym__name(&sym, symstrs); - demangled = demangle_sym(dso, 0, elf_name); - if (demangled != NULL) - elf_name = demangled; - snprintf(sympltname, sizeof(sympltname), - "%s@plt", elf_name); - free(demangled); + for (idx = 0; idx < ri.nr_entries; idx++) { + const char *elf_name = NULL; + char *demangled = NULL; - f = symbol__new(plt_offset, plt_entry_size, - STB_GLOBAL, STT_FUNC, sympltname); - if (!f) - goto out_elf_end; + gelf_getsym(syms, get_rel_symidx(&ri, idx), &sym); - plt_offset += plt_entry_size; - symbols__insert(&dso->symbols, f); - ++nr; - } - } else if (shdr_rel_plt.sh_type == SHT_REL) { - GElf_Rel pos_mem, *pos; - elf_section__for_each_rel(reldata, pos, pos_mem, idx, - nr_rel_entries) { - const char *elf_name = NULL; - char *demangled = NULL; - symidx = GELF_R_SYM(pos->r_info); - gelf_getsym(syms, symidx, &sym); - - elf_name = elf_sym__name(&sym, symstrs); - demangled = demangle_sym(dso, 0, elf_name); - if (demangled != NULL) - elf_name = demangled; + elf_name = elf_sym__name(&sym, symstrs); + demangled = dso__demangle_sym(dso, /*kmodule=*/0, elf_name); + if (demangled) + elf_name = demangled; + if (*elf_name) + snprintf(sympltname, sizeof(sympltname), "%s@plt", elf_name); + else if (!get_ifunc_name(elf, dso, &ehdr, &ri, sympltname, sizeof(sympltname))) snprintf(sympltname, sizeof(sympltname), - "%s@plt", elf_name); - free(demangled); + "offset_%#" PRIx64 "@plt", plt_offset); + free(demangled); - f = symbol__new(plt_offset, plt_entry_size, - STB_GLOBAL, STT_FUNC, sympltname); - if (!f) - goto out_elf_end; + f = symbol__new(plt_offset, plt_entry_size, STB_GLOBAL, STT_FUNC, sympltname); + if (!f) + goto out_elf_end; - plt_offset += plt_entry_size; - symbols__insert(&dso->symbols, f); - ++nr; - } + plt_offset += plt_entry_size; + symbols__insert(dso__symbols(dso), f); + ++nr; } err = 0; out_elf_end: + exit_rel(&ri); if (err == 0) return nr; pr_debug("%s: problems reading %s PLT info.\n", - __func__, dso->long_name); + __func__, dso__long_name(dso)); return 0; } -char *dso__demangle_sym(struct dso *dso, int kmodule, const char *elf_name) -{ - return demangle_sym(dso, kmodule, elf_name); -} - /* * Align offset to 4 bytes as needed for note name and descriptor data. */ @@ -521,7 +860,7 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size) size_t sz = min(size, descsz); memcpy(bf, ptr, sz); memset(bf + sz, 0, size - sz); - err = descsz; + err = sz; break; } } @@ -534,7 +873,7 @@ out: #ifdef HAVE_LIBBFD_BUILDID_SUPPORT -int filename__read_build_id(const char *filename, struct build_id *bid) +static int read_build_id(const char *filename, struct build_id *bid) { size_t size = sizeof(bid->data); int err = -1; @@ -563,7 +902,7 @@ out_close: #else // HAVE_LIBBFD_BUILDID_SUPPORT -int filename__read_build_id(const char *filename, struct build_id *bid) +static int read_build_id(const char *filename, struct build_id *bid) { size_t size = sizeof(bid->data); int fd, err = -1; @@ -595,6 +934,39 @@ out: #endif // HAVE_LIBBFD_BUILDID_SUPPORT +int filename__read_build_id(const char *filename, struct build_id *bid) +{ + struct kmod_path m = { .name = NULL, }; + char path[PATH_MAX]; + int err; + + if (!filename) + return -EFAULT; + + err = kmod_path__parse(&m, filename); + if (err) + return -1; + + if (m.comp) { + int error = 0, fd; + + fd = filename__decompress(filename, path, sizeof(path), m.comp, &error); + if (fd < 0) { + pr_debug("Failed to decompress (error %d) %s\n", + error, filename); + return -1; + } + close(fd); + filename = path; + } + + err = read_build_id(filename, bid); + + if (m.comp) + unlink(filename); + return err; +} + int sysfs__read_build_id(const char *filename, struct build_id *bid) { size_t size = sizeof(bid->data); @@ -737,33 +1109,6 @@ out: #endif -static int dso__swap_init(struct dso *dso, unsigned char eidata) -{ - static unsigned int const endian = 1; - - dso->needs_swap = DSO_SWAP__NO; - - switch (eidata) { - case ELFDATA2LSB: - /* We are big endian, DSO is little endian. */ - if (*(unsigned char const *)&endian != 1) - dso->needs_swap = DSO_SWAP__YES; - break; - - case ELFDATA2MSB: - /* We are little endian, DSO is big endian. */ - if (*(unsigned char const *)&endian != 0) - dso->needs_swap = DSO_SWAP__YES; - break; - - default: - pr_err("unrecognized DSO data encoding %d\n", eidata); - return -EINVAL; - } - - return 0; -} - bool symsrc__possibly_runtime(struct symsrc *ss) { return ss->dynsym || ss->opdsec; @@ -792,6 +1137,81 @@ bool elf__needs_adjust_symbols(GElf_Ehdr ehdr) ehdr.e_type == ET_DYN; } +static Elf *read_gnu_debugdata(struct dso *dso, Elf *elf, const char *name, int *fd_ret) +{ + Elf *elf_embedded; + GElf_Ehdr ehdr; + GElf_Shdr shdr; + Elf_Scn *scn; + Elf_Data *scn_data; + FILE *wrapped; + size_t shndx; + char temp_filename[] = "/tmp/perf.gnu_debugdata.elf.XXXXXX"; + int ret, temp_fd; + + if (gelf_getehdr(elf, &ehdr) == NULL) { + pr_debug("%s: cannot read %s ELF file.\n", __func__, name); + *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; + return NULL; + } + + scn = elf_section_by_name(elf, &ehdr, &shdr, ".gnu_debugdata", &shndx); + if (!scn) { + *dso__load_errno(dso) = -ENOENT; + return NULL; + } + + if (shdr.sh_type == SHT_NOBITS) { + pr_debug("%s: .gnu_debugdata of ELF file %s has no data.\n", __func__, name); + *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; + return NULL; + } + + scn_data = elf_rawdata(scn, NULL); + if (!scn_data) { + pr_debug("%s: error reading .gnu_debugdata of %s: %s\n", __func__, + name, elf_errmsg(-1)); + *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; + return NULL; + } + + wrapped = fmemopen(scn_data->d_buf, scn_data->d_size, "r"); + if (!wrapped) { + pr_debug("%s: fmemopen: %s\n", __func__, strerror(errno)); + *dso__load_errno(dso) = -errno; + return NULL; + } + + temp_fd = mkstemp(temp_filename); + if (temp_fd < 0) { + pr_debug("%s: mkstemp: %s\n", __func__, strerror(errno)); + *dso__load_errno(dso) = -errno; + fclose(wrapped); + return NULL; + } + unlink(temp_filename); + + ret = lzma_decompress_stream_to_file(wrapped, temp_fd); + fclose(wrapped); + if (ret < 0) { + *dso__load_errno(dso) = -errno; + close(temp_fd); + return NULL; + } + + elf_embedded = elf_begin(temp_fd, PERF_ELF_C_READ_MMAP, NULL); + if (!elf_embedded) { + pr_debug("%s: error reading .gnu_debugdata of %s: %s\n", __func__, + name, elf_errmsg(-1)); + *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; + close(temp_fd); + return NULL; + } + pr_debug("%s: using .gnu_debugdata of %s\n", __func__, name); + *fd_ret = temp_fd; + return elf_embedded; +} + int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, enum dso_binary_type type) { @@ -804,11 +1224,11 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, if (fd < 0) return -1; - type = dso->symtab_type; + type = dso__symtab_type(dso); } else { fd = open(name, O_RDONLY); if (fd < 0) { - dso->load_errno = errno; + *dso__load_errno(dso) = errno; return -1; } } @@ -816,45 +1236,59 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); if (elf == NULL) { pr_debug("%s: cannot read %s ELF file.\n", __func__, name); - dso->load_errno = DSO_LOAD_ERRNO__INVALID_ELF; + *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; goto out_close; } + if (type == DSO_BINARY_TYPE__GNU_DEBUGDATA) { + int new_fd; + Elf *embedded = read_gnu_debugdata(dso, elf, name, &new_fd); + + if (!embedded) + goto out_close; + + elf_end(elf); + close(fd); + fd = new_fd; + elf = embedded; + } + if (gelf_getehdr(elf, &ehdr) == NULL) { - dso->load_errno = DSO_LOAD_ERRNO__INVALID_ELF; + *dso__load_errno(dso) = DSO_LOAD_ERRNO__INVALID_ELF; pr_debug("%s: cannot get elf header.\n", __func__); goto out_elf_end; } if (dso__swap_init(dso, ehdr.e_ident[EI_DATA])) { - dso->load_errno = DSO_LOAD_ERRNO__INTERNAL_ERROR; + *dso__load_errno(dso) = DSO_LOAD_ERRNO__INTERNAL_ERROR; goto out_elf_end; } /* Always reject images with a mismatched build-id: */ - if (dso->has_build_id && !symbol_conf.ignore_vmlinux_buildid) { + if (dso__has_build_id(dso) && !symbol_conf.ignore_vmlinux_buildid) { u8 build_id[BUILD_ID_SIZE]; struct build_id bid; int size; size = elf_read_build_id(elf, build_id, BUILD_ID_SIZE); if (size <= 0) { - dso->load_errno = DSO_LOAD_ERRNO__CANNOT_READ_BUILDID; + *dso__load_errno(dso) = DSO_LOAD_ERRNO__CANNOT_READ_BUILDID; goto out_elf_end; } build_id__init(&bid, build_id, size); if (!dso__build_id_equal(dso, &bid)) { pr_debug("%s: build id mismatch for %s.\n", __func__, name); - dso->load_errno = DSO_LOAD_ERRNO__MISMATCHING_BUILDID; + *dso__load_errno(dso) = DSO_LOAD_ERRNO__MISMATCHING_BUILDID; goto out_elf_end; } } ss->is_64_bit = (gelf_getclass(elf) == ELFCLASS64); + ss->symtab_idx = 0; ss->symtab = elf_section_by_name(elf, &ehdr, &ss->symshdr, ".symtab", - NULL); + &ss->symtab_idx); if (ss->symshdr.sh_type != SHT_SYMTAB) ss->symtab = NULL; @@ -870,14 +1304,14 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, if (ss->opdshdr.sh_type != SHT_PROGBITS) ss->opdsec = NULL; - if (dso->kernel == DSO_SPACE__USER) + if (dso__kernel(dso) == DSO_SPACE__USER) ss->adjust_symbols = true; else ss->adjust_symbols = elf__needs_adjust_symbols(ehdr); ss->name = strdup(name); if (!ss->name) { - dso->load_errno = errno; + *dso__load_errno(dso) = errno; goto out_elf_end; } @@ -895,6 +1329,58 @@ out_close: return -1; } +static bool is_exe_text(int flags) +{ + return (flags & (SHF_ALLOC | SHF_EXECINSTR)) == (SHF_ALLOC | SHF_EXECINSTR); +} + +/* + * Some executable module sections like .noinstr.text might be laid out with + * .text so they can use the same mapping (memory address to file offset). + * Check if that is the case. Refer to kernel layout_sections(). Return the + * maximum offset. + */ +static u64 max_text_section(Elf *elf, GElf_Ehdr *ehdr) +{ + Elf_Scn *sec = NULL; + GElf_Shdr shdr; + u64 offs = 0; + + /* Doesn't work for some arch */ + if (ehdr->e_machine == EM_PARISC || + ehdr->e_machine == EM_ALPHA) + return 0; + + /* ELF is corrupted/truncated, avoid calling elf_strptr. */ + if (!elf_rawdata(elf_getscn(elf, ehdr->e_shstrndx), NULL)) + return 0; + + while ((sec = elf_nextscn(elf, sec)) != NULL) { + char *sec_name; + + if (!gelf_getshdr(sec, &shdr)) + break; + + if (!is_exe_text(shdr.sh_flags)) + continue; + + /* .init and .exit sections are not placed with .text */ + sec_name = elf_strptr(elf, ehdr->e_shstrndx, shdr.sh_name); + if (!sec_name || + strstarts(sec_name, ".init") || + strstarts(sec_name, ".exit")) + break; + + /* Must be next to previous, assumes .text is first */ + if (offs && PERF_ALIGN(offs, shdr.sh_addralign ?: 1) != shdr.sh_offset) + break; + + offs = shdr.sh_offset + shdr.sh_size; + } + + return offs; +} + /** * ref_reloc_sym_not_found - has kernel relocation symbol been found. * @kmap: kernel maps and relocation reference symbol @@ -932,9 +1418,10 @@ void __weak arch__sym_update(struct symbol *s __maybe_unused, static int dso__process_kernel_symbol(struct dso *dso, struct map *map, GElf_Sym *sym, GElf_Shdr *shdr, struct maps *kmaps, struct kmap *kmap, - struct dso **curr_dsop, struct map **curr_mapp, + struct dso **curr_dsop, const char *section_name, - bool adjust_kernel_syms, bool kmodule, bool *remap_kernel) + bool adjust_kernel_syms, bool kmodule, bool *remap_kernel, + u64 max_text_sh_offset) { struct dso *curr_dso = *curr_dsop; struct map *curr_map; @@ -944,7 +1431,7 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, if (adjust_kernel_syms) sym->st_value -= shdr->sh_addr - shdr->sh_offset; - if (strcmp(section_name, (curr_dso->short_name + dso->short_name_len)) == 0) + if (strcmp(section_name, (dso__short_name(curr_dso) + dso__short_name_len(dso))) == 0) return 0; if (strcmp(section_name, ".text") == 0) { @@ -953,19 +1440,22 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, * kallsyms and identity maps. Overwrite it to * map to the kernel dso. */ - if (*remap_kernel && dso->kernel && !kmodule) { + if (*remap_kernel && dso__kernel(dso) && !kmodule) { *remap_kernel = false; - map->start = shdr->sh_addr + ref_reloc(kmap); - map->end = map->start + shdr->sh_size; - map->pgoff = shdr->sh_offset; - map->map_ip = map__map_ip; - map->unmap_ip = map__unmap_ip; + map__set_start(map, shdr->sh_addr + ref_reloc(kmap)); + map__set_end(map, map__start(map) + shdr->sh_size); + map__set_pgoff(map, shdr->sh_offset); + map__set_mapping_type(map, MAPPING_TYPE__DSO); /* Ensure maps are correctly ordered */ if (kmaps) { - map__get(map); + int err; + struct map *tmp = map__get(map); + maps__remove(kmaps, map); - maps__insert(kmaps, map); - map__put(map); + err = maps__insert(kmaps, map); + map__put(tmp); + if (err) + return err; } } @@ -976,76 +1466,85 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, */ if (*remap_kernel && kmodule) { *remap_kernel = false; - map->pgoff = shdr->sh_offset; + map__set_pgoff(map, shdr->sh_offset); } - *curr_mapp = map; - *curr_dsop = dso; + dso__put(*curr_dsop); + *curr_dsop = dso__get(dso); return 0; } if (!kmap) return 0; - snprintf(dso_name, sizeof(dso_name), "%s%s", dso->short_name, section_name); + /* + * perf does not record module section addresses except for .text, but + * some sections can use the same mapping as .text. + */ + if (kmodule && adjust_kernel_syms && is_exe_text(shdr->sh_flags) && + shdr->sh_offset <= max_text_sh_offset) { + dso__put(*curr_dsop); + *curr_dsop = dso__get(dso); + return 0; + } + + snprintf(dso_name, sizeof(dso_name), "%s%s", dso__short_name(dso), section_name); curr_map = maps__find_by_name(kmaps, dso_name); if (curr_map == NULL) { u64 start = sym->st_value; if (kmodule) - start += map->start + shdr->sh_offset; + start += map__start(map) + shdr->sh_offset; curr_dso = dso__new(dso_name); if (curr_dso == NULL) return -1; - curr_dso->kernel = dso->kernel; - curr_dso->long_name = dso->long_name; - curr_dso->long_name_len = dso->long_name_len; + dso__set_kernel(curr_dso, dso__kernel(dso)); + RC_CHK_ACCESS(curr_dso)->long_name = dso__long_name(dso); + RC_CHK_ACCESS(curr_dso)->long_name_len = dso__long_name_len(dso); + dso__set_binary_type(curr_dso, dso__binary_type(dso)); + dso__set_adjust_symbols(curr_dso, dso__adjust_symbols(dso)); curr_map = map__new2(start, curr_dso); - dso__put(curr_dso); - if (curr_map == NULL) + if (curr_map == NULL) { + dso__put(curr_dso); return -1; - - if (curr_dso->kernel) + } + if (dso__kernel(curr_dso)) map__kmap(curr_map)->kmaps = kmaps; if (adjust_kernel_syms) { - curr_map->start = shdr->sh_addr + ref_reloc(kmap); - curr_map->end = curr_map->start + shdr->sh_size; - curr_map->pgoff = shdr->sh_offset; + map__set_start(curr_map, shdr->sh_addr + ref_reloc(kmap)); + map__set_end(curr_map, map__start(curr_map) + shdr->sh_size); + map__set_pgoff(curr_map, shdr->sh_offset); } else { - curr_map->map_ip = curr_map->unmap_ip = identity__map_ip; + map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY); } - curr_dso->symtab_type = dso->symtab_type; - maps__insert(kmaps, curr_map); - /* - * Add it before we drop the referece to curr_map, i.e. while - * we still are sure to have a reference to this DSO via - * *curr_map->dso. - */ - dsos__add(&kmaps->machine->dsos, curr_dso); - /* kmaps already got it */ - map__put(curr_map); + dso__set_symtab_type(curr_dso, dso__symtab_type(dso)); + if (maps__insert(kmaps, curr_map)) + return -1; + dsos__add(&maps__machine(kmaps)->dsos, curr_dso); dso__set_loaded(curr_dso); - *curr_mapp = curr_map; + dso__put(*curr_dsop); *curr_dsop = curr_dso; - } else - *curr_dsop = curr_map->dso; + } else { + dso__put(*curr_dsop); + *curr_dsop = dso__get(map__dso(curr_map)); + } + map__put(curr_map); return 0; } -int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, - struct symsrc *runtime_ss, int kmodule) +static int +dso__load_sym_internal(struct dso *dso, struct map *map, struct symsrc *syms_ss, + struct symsrc *runtime_ss, int kmodule, int dynsym) { - struct kmap *kmap = dso->kernel ? map__kmap(map) : NULL; + struct kmap *kmap = dso__kernel(dso) ? map__kmap(map) : NULL; struct maps *kmaps = kmap ? map__kmaps(map) : NULL; - struct map *curr_map = map; - struct dso *curr_dso = dso; - Elf_Data *symstrs, *secstrs; + struct dso *curr_dso = NULL; + Elf_Data *symstrs, *secstrs, *secstrs_run, *secstrs_sym; uint32_t nr_syms; - int err = -1; uint32_t idx; GElf_Ehdr ehdr; GElf_Shdr shdr; @@ -1056,42 +1555,26 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, Elf *elf; int nr = 0; bool remap_kernel = false, adjust_kernel_syms = false; + u64 max_text_sh_offset = 0; if (kmap && !kmaps) return -1; - dso->symtab_type = syms_ss->type; - dso->is_64_bit = syms_ss->is_64_bit; - dso->rel = syms_ss->ehdr.e_type == ET_REL; - - /* - * Modules may already have symbols from kallsyms, but those symbols - * have the wrong values for the dso maps, so remove them. - */ - if (kmodule && syms_ss->symtab) - symbols__delete(&dso->symbols); - - if (!syms_ss->symtab) { - /* - * If the vmlinux is stripped, fail so we will fall back - * to using kallsyms. The vmlinux runtime symbols aren't - * of much use. - */ - if (dso->kernel) - goto out_elf_end; - - syms_ss->symtab = syms_ss->dynsym; - syms_ss->symshdr = syms_ss->dynshdr; - } - elf = syms_ss->elf; ehdr = syms_ss->ehdr; - sec = syms_ss->symtab; - shdr = syms_ss->symshdr; + if (dynsym) { + sec = syms_ss->dynsym; + shdr = syms_ss->dynshdr; + } else { + sec = syms_ss->symtab; + shdr = syms_ss->symshdr; + } if (elf_section_by_name(runtime_ss->elf, &runtime_ss->ehdr, &tshdr, - ".text", NULL)) - dso->text_offset = tshdr.sh_addr - tshdr.sh_offset; + ".text", NULL)) { + dso__set_text_offset(dso, tshdr.sh_addr - tshdr.sh_offset); + dso__set_text_end(dso, tshdr.sh_offset + tshdr.sh_size); + } if (runtime_ss->opdsec) opddata = elf_rawdata(runtime_ss->opdsec, NULL); @@ -1112,8 +1595,16 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, if (sec_strndx == NULL) goto out_elf_end; - secstrs = elf_getdata(sec_strndx, NULL); - if (secstrs == NULL) + secstrs_run = elf_getdata(sec_strndx, NULL); + if (secstrs_run == NULL) + goto out_elf_end; + + sec_strndx = elf_getscn(elf, ehdr.e_shstrndx); + if (sec_strndx == NULL) + goto out_elf_end; + + secstrs_sym = elf_getdata(sec_strndx, NULL); + if (secstrs_sym == NULL) goto out_elf_end; nr_syms = shdr.sh_size / shdr.sh_entsize; @@ -1131,8 +1622,7 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, if (strcmp(elf_name, kmap->ref_reloc_sym->name)) continue; kmap->ref_reloc_sym->unrelocated_addr = sym.st_value; - map->reloc = kmap->ref_reloc_sym->addr - - kmap->ref_reloc_sym->unrelocated_addr; + map__set_reloc(map, kmap->ref_reloc_sym->addr - kmap->ref_reloc_sym->unrelocated_addr); break; } } @@ -1142,17 +1632,22 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, * attempted to prelink vdso to its virtual address. */ if (dso__is_vdso(dso)) - map->reloc = map->start - dso->text_offset; + map__set_reloc(map, map__start(map) - dso__text_offset(dso)); - dso->adjust_symbols = runtime_ss->adjust_symbols || ref_reloc(kmap); + dso__set_adjust_symbols(dso, runtime_ss->adjust_symbols || ref_reloc(kmap)); /* * Initial kernel and module mappings do not map to the dso. * Flag the fixups. */ - if (dso->kernel) { + if (dso__kernel(dso)) { remap_kernel = true; - adjust_kernel_syms = dso->adjust_symbols; + adjust_kernel_syms = dso__adjust_symbols(dso); } + + if (kmodule && adjust_kernel_syms) + max_text_sh_offset = max_text_section(runtime_ss->elf, &runtime_ss->ehdr); + + curr_dso = dso__get(dso); elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) { struct symbol *f; const char *elf_name = elf_sym__name(&sym, symstrs); @@ -1173,6 +1668,12 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, continue; } + /* Reject RISCV ELF "mapping symbols" */ + if (ehdr.e_machine == EM_RISCV) { + if (elf_name[0] == '$' && strchr("dx", elf_name[1])) + continue; + } + if (runtime_ss->opdsec && sym.st_shndx == runtime_ss->opdidx) { u32 offset = sym.st_value - syms_ss->opdshdr.sh_addr; u64 *opd = opddata->d_buf + offset; @@ -1181,6 +1682,7 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, sym.st_value); used_opd = true; } + /* * When loading symbols in a data mapping, ABS symbols (which * has a value of SHN_ABS in its st_shndx) failed at @@ -1193,12 +1695,40 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, if (sym.st_shndx == SHN_ABS) continue; - sec = elf_getscn(runtime_ss->elf, sym.st_shndx); + sec = elf_getscn(syms_ss->elf, sym.st_shndx); if (!sec) goto out_elf_end; gelf_getshdr(sec, &shdr); + /* + * If the attribute bit SHF_ALLOC is not set, the section + * doesn't occupy memory during process execution. + * E.g. ".gnu.warning.*" section is used by linker to generate + * warnings when calling deprecated functions, the symbols in + * the section aren't loaded to memory during process execution, + * so skip them. + */ + if (!(shdr.sh_flags & SHF_ALLOC)) + continue; + + secstrs = secstrs_sym; + + /* + * We have to fallback to runtime when syms' section header has + * NOBITS set. NOBITS results in file offset (sh_offset) not + * being incremented. So sh_offset used below has different + * values for syms (invalid) and runtime (valid). + */ + if (shdr.sh_type == SHT_NOBITS) { + sec = elf_getscn(runtime_ss->elf, sym.st_shndx); + if (!sec) + goto out_elf_end; + + gelf_getshdr(sec, &shdr); + secstrs = secstrs_run; + } + if (is_label && !elf_sec__filter(&shdr, secstrs)) continue; @@ -1211,20 +1741,47 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, (sym.st_value & 1)) --sym.st_value; - if (dso->kernel) { - if (dso__process_kernel_symbol(dso, map, &sym, &shdr, kmaps, kmap, &curr_dso, &curr_map, - section_name, adjust_kernel_syms, kmodule, &remap_kernel)) + if (dso__kernel(dso)) { + if (dso__process_kernel_symbol(dso, map, &sym, &shdr, + kmaps, kmap, &curr_dso, + section_name, + adjust_kernel_syms, + kmodule, + &remap_kernel, + max_text_sh_offset)) goto out_elf_end; } else if ((used_opd && runtime_ss->adjust_symbols) || (!used_opd && syms_ss->adjust_symbols)) { - pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " " - "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", __func__, - (u64)sym.st_value, (u64)shdr.sh_addr, - (u64)shdr.sh_offset); - sym.st_value -= shdr.sh_addr - shdr.sh_offset; + GElf_Phdr phdr; + + if (elf_read_program_header(runtime_ss->elf, + (u64)sym.st_value, &phdr)) { + pr_debug4("%s: failed to find program header for " + "symbol: %s st_value: %#" PRIx64 "\n", + __func__, elf_name, (u64)sym.st_value); + pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " " + "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", + __func__, (u64)sym.st_value, (u64)shdr.sh_addr, + (u64)shdr.sh_offset); + /* + * Fail to find program header, let's rollback + * to use shdr.sh_addr and shdr.sh_offset to + * calibrate symbol's file address, though this + * is not necessary for normal C ELF file, we + * still need to handle java JIT symbols in this + * case. + */ + sym.st_value -= shdr.sh_addr - shdr.sh_offset; + } else { + pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " " + "p_vaddr: %#" PRIx64 " p_offset: %#" PRIx64 "\n", + __func__, (u64)sym.st_value, (u64)phdr.p_vaddr, + (u64)phdr.p_offset); + sym.st_value -= phdr.p_vaddr - phdr.p_offset; + } } - demangled = demangle_sym(dso, kmodule, elf_name); + demangled = dso__demangle_sym(dso, kmodule, elf_name); if (demangled != NULL) elf_name = demangled; @@ -1237,16 +1794,17 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, arch__sym_update(f, &sym); - __symbols__insert(&curr_dso->symbols, f, dso->kernel); + __symbols__insert(dso__symbols(curr_dso), f, dso__kernel(dso)); nr++; } + dso__put(curr_dso); /* * For misannotated, zeroed, ASM function sizes. */ if (nr > 0) { - symbols__fixup_end(&dso->symbols); - symbols__fixup_duplicate(&dso->symbols); + symbols__fixup_end(dso__symbols(dso), false); + symbols__fixup_duplicate(dso__symbols(dso)); if (kmap) { /* * We need to fixup this here too because we create new @@ -1255,9 +1813,67 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, maps__fixup_end(kmaps); } } - err = nr; + return nr; out_elf_end: - return err; + dso__put(curr_dso); + return -1; +} + +int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, + struct symsrc *runtime_ss, int kmodule) +{ + int nr = 0; + int err = -1; + + dso__set_symtab_type(dso, syms_ss->type); + dso__set_is_64_bit(dso, syms_ss->is_64_bit); + dso__set_rel(dso, syms_ss->ehdr.e_type == ET_REL); + + /* + * Modules may already have symbols from kallsyms, but those symbols + * have the wrong values for the dso maps, so remove them. + */ + if (kmodule && syms_ss->symtab) + symbols__delete(dso__symbols(dso)); + + if (!syms_ss->symtab) { + /* + * If the vmlinux is stripped, fail so we will fall back + * to using kallsyms. The vmlinux runtime symbols aren't + * of much use. + */ + if (dso__kernel(dso)) + return err; + } else { + err = dso__load_sym_internal(dso, map, syms_ss, runtime_ss, + kmodule, 0); + if (err < 0) + return err; + nr = err; + } + + if (syms_ss->dynsym) { + err = dso__load_sym_internal(dso, map, syms_ss, runtime_ss, + kmodule, 1); + if (err < 0) + return err; + nr += err; + } + + /* + * The .gnu_debugdata is a special situation: it contains a symbol + * table, but the runtime file may also contain dynsym entries which are + * not present there. We need to load both. + */ + if (syms_ss->type == DSO_BINARY_TYPE__GNU_DEBUGDATA && runtime_ss->dynsym) { + err = dso__load_sym_internal(dso, map, runtime_ss, runtime_ss, + kmodule, 1); + if (err < 0) + return err; + nr += err; + } + + return nr; } static int elf_read_maps(Elf *elf, bool exe, mapfn_t mapfn, void *data) @@ -1952,8 +2568,8 @@ static int kcore_copy__compare_file(const char *from_dir, const char *to_dir, * unusual. One significant peculiarity is that the mapping (start -> pgoff) * is not the same for the kernel map and the modules map. That happens because * the data is copied adjacently whereas the original kcore has gaps. Finally, - * kallsyms and modules files are compared with their copies to check that - * modules have not been loaded or unloaded while the copies were taking place. + * kallsyms file is compared with its copy to check that modules have not been + * loaded or unloaded while the copies were taking place. * * Return: %0 on success, %-1 on failure. */ @@ -2016,9 +2632,6 @@ int kcore_copy(const char *from_dir, const char *to_dir) goto out_extract_close; } - if (kcore_copy__compare_file(from_dir, to_dir, "modules")) - goto out_extract_close; - if (kcore_copy__compare_file(from_dir, to_dir, "kallsyms")) goto out_extract_close; @@ -2360,6 +2973,7 @@ int cleanup_sdt_note_list(struct list_head *sdt_notes) list_for_each_entry_safe(pos, tmp, sdt_notes, note_list) { list_del_init(&pos->note_list); + zfree(&pos->args); zfree(&pos->name); zfree(&pos->provider); free(pos); |