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https://github.com/edk2-porting/linux-next.git
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b68e2f919c
Factors opening of certain sections & tracking certain elf info into an external structure. The goal here is to keep multiple elfs (and their looked up sections/indexes) around during the symbol generation process (in dso__load()). We need this to properly resolve symbols on PPC due to the use of function descriptors & the .opd section (ie: symbols which are functions don't point to their actual location, they point to their function descriptor in .opd which contains their actual location. It would be possible to just keep the (Elf *) around, but then we'd end up with duplicate code for looking up the same sections and checking for the existence of an important section wouldn't be as clean (and we need to keep the Elf stuff confined to symtab-elf.c). Utilized by the later patch "perf symbols: Use both runtime and debug images" Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Cc: David Hansen <dave@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Matt Hellsley <matthltc@us.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1344637382-22789-12-git-send-email-cody@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
843 lines
18 KiB
C
843 lines
18 KiB
C
#include <libelf.h>
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#include <gelf.h>
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#include <elf.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <errno.h>
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#include <string.h>
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#include <unistd.h>
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#include <inttypes.h>
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#include "symbol.h"
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#include "debug.h"
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#ifndef NT_GNU_BUILD_ID
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#define NT_GNU_BUILD_ID 3
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#endif
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/**
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* elf_symtab__for_each_symbol - iterate thru all the symbols
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*
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* @syms: struct elf_symtab instance to iterate
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* @idx: uint32_t idx
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* @sym: GElf_Sym iterator
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*/
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#define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
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for (idx = 0, gelf_getsym(syms, idx, &sym);\
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idx < nr_syms; \
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idx++, gelf_getsym(syms, idx, &sym))
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static inline uint8_t elf_sym__type(const GElf_Sym *sym)
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{
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return GELF_ST_TYPE(sym->st_info);
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}
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static inline int elf_sym__is_function(const GElf_Sym *sym)
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{
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return elf_sym__type(sym) == STT_FUNC &&
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sym->st_name != 0 &&
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sym->st_shndx != SHN_UNDEF;
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}
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static inline bool elf_sym__is_object(const GElf_Sym *sym)
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{
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return elf_sym__type(sym) == STT_OBJECT &&
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sym->st_name != 0 &&
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sym->st_shndx != SHN_UNDEF;
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}
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static inline int elf_sym__is_label(const GElf_Sym *sym)
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{
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return elf_sym__type(sym) == STT_NOTYPE &&
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sym->st_name != 0 &&
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sym->st_shndx != SHN_UNDEF &&
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sym->st_shndx != SHN_ABS;
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}
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static bool elf_sym__is_a(GElf_Sym *sym, enum map_type type)
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{
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switch (type) {
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case MAP__FUNCTION:
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return elf_sym__is_function(sym);
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case MAP__VARIABLE:
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return elf_sym__is_object(sym);
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default:
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return false;
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}
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}
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static inline const char *elf_sym__name(const GElf_Sym *sym,
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const Elf_Data *symstrs)
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{
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return symstrs->d_buf + sym->st_name;
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}
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static inline const char *elf_sec__name(const GElf_Shdr *shdr,
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const Elf_Data *secstrs)
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{
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return secstrs->d_buf + shdr->sh_name;
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}
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static inline int elf_sec__is_text(const GElf_Shdr *shdr,
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const Elf_Data *secstrs)
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{
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return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
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}
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static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
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const Elf_Data *secstrs)
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{
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return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
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}
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static bool elf_sec__is_a(GElf_Shdr *shdr, Elf_Data *secstrs,
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enum map_type type)
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{
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switch (type) {
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case MAP__FUNCTION:
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return elf_sec__is_text(shdr, secstrs);
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case MAP__VARIABLE:
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return elf_sec__is_data(shdr, secstrs);
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default:
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return false;
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}
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}
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static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr)
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{
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Elf_Scn *sec = NULL;
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GElf_Shdr shdr;
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size_t cnt = 1;
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while ((sec = elf_nextscn(elf, sec)) != NULL) {
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gelf_getshdr(sec, &shdr);
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if ((addr >= shdr.sh_addr) &&
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(addr < (shdr.sh_addr + shdr.sh_size)))
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return cnt;
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++cnt;
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}
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return -1;
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}
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static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
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GElf_Shdr *shp, const char *name,
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size_t *idx)
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{
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Elf_Scn *sec = NULL;
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size_t cnt = 1;
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/* Elf is corrupted/truncated, avoid calling elf_strptr. */
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if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL))
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return NULL;
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while ((sec = elf_nextscn(elf, sec)) != NULL) {
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char *str;
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gelf_getshdr(sec, shp);
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str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
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if (!strcmp(name, str)) {
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if (idx)
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*idx = cnt;
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break;
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}
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++cnt;
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}
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return sec;
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}
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#define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
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for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
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idx < nr_entries; \
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++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
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#define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
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for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
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idx < nr_entries; \
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++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
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/*
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* We need to check if we have a .dynsym, so that we can handle the
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* .plt, synthesizing its symbols, that aren't on the symtabs (be it
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* .dynsym or .symtab).
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* And always look at the original dso, not at debuginfo packages, that
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* have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
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*/
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int dso__synthesize_plt_symbols(struct dso *dso, char *name, struct map *map,
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symbol_filter_t filter)
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{
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uint32_t nr_rel_entries, idx;
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GElf_Sym sym;
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u64 plt_offset;
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GElf_Shdr shdr_plt;
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struct symbol *f;
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GElf_Shdr shdr_rel_plt, shdr_dynsym;
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Elf_Data *reldata, *syms, *symstrs;
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Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
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size_t dynsym_idx;
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GElf_Ehdr ehdr;
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char sympltname[1024];
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Elf *elf;
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int nr = 0, symidx, fd, err = 0;
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fd = open(name, O_RDONLY);
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if (fd < 0)
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goto out;
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elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
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if (elf == NULL)
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goto out_close;
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if (gelf_getehdr(elf, &ehdr) == NULL)
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goto out_elf_end;
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scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
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".dynsym", &dynsym_idx);
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if (scn_dynsym == NULL)
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goto out_elf_end;
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scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
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".rela.plt", NULL);
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if (scn_plt_rel == NULL) {
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scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
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".rel.plt", NULL);
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if (scn_plt_rel == NULL)
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goto out_elf_end;
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}
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err = -1;
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if (shdr_rel_plt.sh_link != dynsym_idx)
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goto out_elf_end;
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if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
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goto out_elf_end;
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/*
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* Fetch the relocation section to find the idxes to the GOT
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* and the symbols in the .dynsym they refer to.
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*/
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reldata = elf_getdata(scn_plt_rel, NULL);
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if (reldata == NULL)
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goto out_elf_end;
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syms = elf_getdata(scn_dynsym, NULL);
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if (syms == NULL)
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goto out_elf_end;
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scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
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if (scn_symstrs == NULL)
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goto out_elf_end;
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symstrs = elf_getdata(scn_symstrs, NULL);
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if (symstrs == NULL)
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goto out_elf_end;
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if (symstrs->d_size == 0)
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goto out_elf_end;
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nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
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plt_offset = shdr_plt.sh_offset;
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if (shdr_rel_plt.sh_type == SHT_RELA) {
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GElf_Rela pos_mem, *pos;
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elf_section__for_each_rela(reldata, pos, pos_mem, idx,
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nr_rel_entries) {
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symidx = GELF_R_SYM(pos->r_info);
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plt_offset += shdr_plt.sh_entsize;
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gelf_getsym(syms, symidx, &sym);
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snprintf(sympltname, sizeof(sympltname),
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"%s@plt", elf_sym__name(&sym, symstrs));
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f = symbol__new(plt_offset, shdr_plt.sh_entsize,
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STB_GLOBAL, sympltname);
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if (!f)
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goto out_elf_end;
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if (filter && filter(map, f))
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symbol__delete(f);
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else {
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symbols__insert(&dso->symbols[map->type], f);
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++nr;
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}
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}
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} else if (shdr_rel_plt.sh_type == SHT_REL) {
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GElf_Rel pos_mem, *pos;
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elf_section__for_each_rel(reldata, pos, pos_mem, idx,
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nr_rel_entries) {
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symidx = GELF_R_SYM(pos->r_info);
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plt_offset += shdr_plt.sh_entsize;
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gelf_getsym(syms, symidx, &sym);
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snprintf(sympltname, sizeof(sympltname),
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"%s@plt", elf_sym__name(&sym, symstrs));
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f = symbol__new(plt_offset, shdr_plt.sh_entsize,
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STB_GLOBAL, sympltname);
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if (!f)
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goto out_elf_end;
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if (filter && filter(map, f))
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symbol__delete(f);
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else {
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symbols__insert(&dso->symbols[map->type], f);
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++nr;
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}
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}
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}
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err = 0;
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out_elf_end:
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elf_end(elf);
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out_close:
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close(fd);
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if (err == 0)
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return nr;
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out:
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pr_debug("%s: problems reading %s PLT info.\n",
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__func__, dso->long_name);
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return 0;
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}
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/*
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* Align offset to 4 bytes as needed for note name and descriptor data.
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*/
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#define NOTE_ALIGN(n) (((n) + 3) & -4U)
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static int elf_read_build_id(Elf *elf, void *bf, size_t size)
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{
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int err = -1;
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GElf_Ehdr ehdr;
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GElf_Shdr shdr;
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Elf_Data *data;
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Elf_Scn *sec;
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Elf_Kind ek;
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void *ptr;
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if (size < BUILD_ID_SIZE)
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goto out;
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ek = elf_kind(elf);
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if (ek != ELF_K_ELF)
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goto out;
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if (gelf_getehdr(elf, &ehdr) == NULL) {
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pr_err("%s: cannot get elf header.\n", __func__);
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goto out;
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}
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/*
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* Check following sections for notes:
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* '.note.gnu.build-id'
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* '.notes'
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* '.note' (VDSO specific)
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*/
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do {
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sec = elf_section_by_name(elf, &ehdr, &shdr,
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".note.gnu.build-id", NULL);
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if (sec)
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break;
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sec = elf_section_by_name(elf, &ehdr, &shdr,
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".notes", NULL);
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if (sec)
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break;
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sec = elf_section_by_name(elf, &ehdr, &shdr,
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".note", NULL);
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if (sec)
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break;
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return err;
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} while (0);
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data = elf_getdata(sec, NULL);
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if (data == NULL)
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goto out;
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ptr = data->d_buf;
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while (ptr < (data->d_buf + data->d_size)) {
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GElf_Nhdr *nhdr = ptr;
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size_t namesz = NOTE_ALIGN(nhdr->n_namesz),
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descsz = NOTE_ALIGN(nhdr->n_descsz);
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const char *name;
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ptr += sizeof(*nhdr);
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name = ptr;
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ptr += namesz;
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if (nhdr->n_type == NT_GNU_BUILD_ID &&
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nhdr->n_namesz == sizeof("GNU")) {
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if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
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size_t sz = min(size, descsz);
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memcpy(bf, ptr, sz);
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memset(bf + sz, 0, size - sz);
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err = descsz;
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break;
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}
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}
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ptr += descsz;
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}
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out:
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return err;
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}
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int filename__read_build_id(const char *filename, void *bf, size_t size)
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{
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int fd, err = -1;
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Elf *elf;
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if (size < BUILD_ID_SIZE)
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goto out;
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fd = open(filename, O_RDONLY);
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if (fd < 0)
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goto out;
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elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
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if (elf == NULL) {
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pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
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goto out_close;
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}
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err = elf_read_build_id(elf, bf, size);
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elf_end(elf);
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out_close:
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close(fd);
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out:
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return err;
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}
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int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
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{
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int fd, err = -1;
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if (size < BUILD_ID_SIZE)
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goto out;
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fd = open(filename, O_RDONLY);
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if (fd < 0)
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goto out;
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while (1) {
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char bf[BUFSIZ];
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GElf_Nhdr nhdr;
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size_t namesz, descsz;
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if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
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break;
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namesz = NOTE_ALIGN(nhdr.n_namesz);
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descsz = NOTE_ALIGN(nhdr.n_descsz);
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if (nhdr.n_type == NT_GNU_BUILD_ID &&
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nhdr.n_namesz == sizeof("GNU")) {
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if (read(fd, bf, namesz) != (ssize_t)namesz)
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break;
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if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
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size_t sz = min(descsz, size);
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if (read(fd, build_id, sz) == (ssize_t)sz) {
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memset(build_id + sz, 0, size - sz);
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err = 0;
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break;
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}
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} else if (read(fd, bf, descsz) != (ssize_t)descsz)
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break;
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} else {
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int n = namesz + descsz;
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if (read(fd, bf, n) != n)
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break;
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}
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}
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close(fd);
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out:
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return err;
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}
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int filename__read_debuglink(const char *filename, char *debuglink,
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size_t size)
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{
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int fd, err = -1;
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Elf *elf;
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GElf_Ehdr ehdr;
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GElf_Shdr shdr;
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Elf_Data *data;
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Elf_Scn *sec;
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Elf_Kind ek;
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fd = open(filename, O_RDONLY);
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if (fd < 0)
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goto out;
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elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
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if (elf == NULL) {
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pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
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goto out_close;
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}
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ek = elf_kind(elf);
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if (ek != ELF_K_ELF)
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goto out_close;
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if (gelf_getehdr(elf, &ehdr) == NULL) {
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pr_err("%s: cannot get elf header.\n", __func__);
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goto out_close;
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}
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|
|
sec = elf_section_by_name(elf, &ehdr, &shdr,
|
|
".gnu_debuglink", NULL);
|
|
if (sec == NULL)
|
|
goto out_close;
|
|
|
|
data = elf_getdata(sec, NULL);
|
|
if (data == NULL)
|
|
goto out_close;
|
|
|
|
/* the start of this section is a zero-terminated string */
|
|
strncpy(debuglink, data->d_buf, size);
|
|
|
|
elf_end(elf);
|
|
|
|
out_close:
|
|
close(fd);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
|
|
void symsrc__destroy(struct symsrc *ss)
|
|
{
|
|
free(ss->name);
|
|
elf_end(ss->elf);
|
|
close(ss->fd);
|
|
}
|
|
|
|
int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
|
|
enum dso_binary_type type)
|
|
{
|
|
int err = -1;
|
|
GElf_Ehdr ehdr;
|
|
Elf *elf;
|
|
int fd;
|
|
|
|
fd = open(name, O_RDONLY);
|
|
if (fd < 0)
|
|
return -1;
|
|
|
|
elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
|
|
if (elf == NULL) {
|
|
pr_debug("%s: cannot read %s ELF file.\n", __func__, name);
|
|
goto out_close;
|
|
}
|
|
|
|
if (gelf_getehdr(elf, &ehdr) == NULL) {
|
|
pr_debug("%s: cannot get elf header.\n", __func__);
|
|
goto out_elf_end;
|
|
}
|
|
|
|
if (dso__swap_init(dso, ehdr.e_ident[EI_DATA]))
|
|
goto out_elf_end;
|
|
|
|
/* Always reject images with a mismatched build-id: */
|
|
if (dso->has_build_id) {
|
|
u8 build_id[BUILD_ID_SIZE];
|
|
|
|
if (elf_read_build_id(elf, build_id, BUILD_ID_SIZE) < 0)
|
|
goto out_elf_end;
|
|
|
|
if (!dso__build_id_equal(dso, build_id))
|
|
goto out_elf_end;
|
|
}
|
|
|
|
ss->symtab = elf_section_by_name(elf, &ehdr, &ss->symshdr, ".symtab",
|
|
NULL);
|
|
if (ss->symshdr.sh_type != SHT_SYMTAB)
|
|
ss->symtab = NULL;
|
|
|
|
ss->dynsym_idx = 0;
|
|
ss->dynsym = elf_section_by_name(elf, &ehdr, &ss->dynshdr, ".dynsym",
|
|
&ss->dynsym_idx);
|
|
if (ss->dynshdr.sh_type != SHT_DYNSYM)
|
|
ss->dynsym = NULL;
|
|
|
|
ss->opdidx = 0;
|
|
ss->opdsec = elf_section_by_name(elf, &ehdr, &ss->opdshdr, ".opd",
|
|
&ss->opdidx);
|
|
if (ss->opdshdr.sh_type != SHT_PROGBITS)
|
|
ss->opdsec = NULL;
|
|
|
|
if (dso->kernel == DSO_TYPE_USER) {
|
|
GElf_Shdr shdr;
|
|
ss->adjust_symbols = (ehdr.e_type == ET_EXEC ||
|
|
elf_section_by_name(elf, &ehdr, &shdr,
|
|
".gnu.prelink_undo",
|
|
NULL) != NULL);
|
|
} else {
|
|
ss->adjust_symbols = 0;
|
|
}
|
|
|
|
ss->name = strdup(name);
|
|
if (!ss->name)
|
|
goto out_elf_end;
|
|
|
|
ss->elf = elf;
|
|
ss->fd = fd;
|
|
ss->ehdr = ehdr;
|
|
ss->type = type;
|
|
|
|
return 0;
|
|
|
|
out_elf_end:
|
|
elf_end(elf);
|
|
out_close:
|
|
close(fd);
|
|
return err;
|
|
}
|
|
|
|
int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *ss,
|
|
symbol_filter_t filter, int kmodule, int want_symtab)
|
|
{
|
|
struct kmap *kmap = dso->kernel ? map__kmap(map) : NULL;
|
|
struct map *curr_map = map;
|
|
struct dso *curr_dso = dso;
|
|
Elf_Data *symstrs, *secstrs;
|
|
uint32_t nr_syms;
|
|
int err = -1;
|
|
uint32_t idx;
|
|
GElf_Ehdr ehdr;
|
|
GElf_Shdr shdr, opdshdr;
|
|
Elf_Data *syms, *opddata = NULL;
|
|
GElf_Sym sym;
|
|
Elf_Scn *sec, *sec_strndx, *opdsec;
|
|
Elf *elf;
|
|
int nr = 0;
|
|
size_t opdidx = 0;
|
|
|
|
elf = ss->elf;
|
|
ehdr = ss->ehdr;
|
|
sec = ss->symtab;
|
|
shdr = ss->symshdr;
|
|
|
|
if (sec == NULL) {
|
|
if (want_symtab)
|
|
goto out_elf_end;
|
|
|
|
sec = ss->dynsym;
|
|
shdr = ss->dynshdr;
|
|
if (sec == NULL)
|
|
goto out_elf_end;
|
|
}
|
|
|
|
opdsec = ss->opdsec;
|
|
opdshdr = ss->opdshdr;
|
|
opdidx = ss->opdidx;
|
|
if (opdsec)
|
|
opddata = elf_rawdata(opdsec, NULL);
|
|
|
|
syms = elf_getdata(sec, NULL);
|
|
if (syms == NULL)
|
|
goto out_elf_end;
|
|
|
|
sec = elf_getscn(elf, shdr.sh_link);
|
|
if (sec == NULL)
|
|
goto out_elf_end;
|
|
|
|
symstrs = elf_getdata(sec, NULL);
|
|
if (symstrs == NULL)
|
|
goto out_elf_end;
|
|
|
|
sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
|
|
if (sec_strndx == NULL)
|
|
goto out_elf_end;
|
|
|
|
secstrs = elf_getdata(sec_strndx, NULL);
|
|
if (secstrs == NULL)
|
|
goto out_elf_end;
|
|
|
|
nr_syms = shdr.sh_size / shdr.sh_entsize;
|
|
|
|
memset(&sym, 0, sizeof(sym));
|
|
dso->adjust_symbols = ss->adjust_symbols;
|
|
elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
|
|
struct symbol *f;
|
|
const char *elf_name = elf_sym__name(&sym, symstrs);
|
|
char *demangled = NULL;
|
|
int is_label = elf_sym__is_label(&sym);
|
|
const char *section_name;
|
|
|
|
if (kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
|
|
strcmp(elf_name, kmap->ref_reloc_sym->name) == 0)
|
|
kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
|
|
|
|
if (!is_label && !elf_sym__is_a(&sym, map->type))
|
|
continue;
|
|
|
|
/* Reject ARM ELF "mapping symbols": these aren't unique and
|
|
* don't identify functions, so will confuse the profile
|
|
* output: */
|
|
if (ehdr.e_machine == EM_ARM) {
|
|
if (!strcmp(elf_name, "$a") ||
|
|
!strcmp(elf_name, "$d") ||
|
|
!strcmp(elf_name, "$t"))
|
|
continue;
|
|
}
|
|
|
|
if (opdsec && sym.st_shndx == opdidx) {
|
|
u32 offset = sym.st_value - opdshdr.sh_addr;
|
|
u64 *opd = opddata->d_buf + offset;
|
|
sym.st_value = DSO__SWAP(dso, u64, *opd);
|
|
sym.st_shndx = elf_addr_to_index(elf, sym.st_value);
|
|
}
|
|
|
|
sec = elf_getscn(elf, sym.st_shndx);
|
|
if (!sec)
|
|
goto out_elf_end;
|
|
|
|
gelf_getshdr(sec, &shdr);
|
|
|
|
if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type))
|
|
continue;
|
|
|
|
section_name = elf_sec__name(&shdr, secstrs);
|
|
|
|
/* On ARM, symbols for thumb functions have 1 added to
|
|
* the symbol address as a flag - remove it */
|
|
if ((ehdr.e_machine == EM_ARM) &&
|
|
(map->type == MAP__FUNCTION) &&
|
|
(sym.st_value & 1))
|
|
--sym.st_value;
|
|
|
|
if (dso->kernel != DSO_TYPE_USER || kmodule) {
|
|
char dso_name[PATH_MAX];
|
|
|
|
if (strcmp(section_name,
|
|
(curr_dso->short_name +
|
|
dso->short_name_len)) == 0)
|
|
goto new_symbol;
|
|
|
|
if (strcmp(section_name, ".text") == 0) {
|
|
curr_map = map;
|
|
curr_dso = dso;
|
|
goto new_symbol;
|
|
}
|
|
|
|
snprintf(dso_name, sizeof(dso_name),
|
|
"%s%s", dso->short_name, section_name);
|
|
|
|
curr_map = map_groups__find_by_name(kmap->kmaps, map->type, dso_name);
|
|
if (curr_map == NULL) {
|
|
u64 start = sym.st_value;
|
|
|
|
if (kmodule)
|
|
start += map->start + shdr.sh_offset;
|
|
|
|
curr_dso = dso__new(dso_name);
|
|
if (curr_dso == NULL)
|
|
goto out_elf_end;
|
|
curr_dso->kernel = dso->kernel;
|
|
curr_dso->long_name = dso->long_name;
|
|
curr_dso->long_name_len = dso->long_name_len;
|
|
curr_map = map__new2(start, curr_dso,
|
|
map->type);
|
|
if (curr_map == NULL) {
|
|
dso__delete(curr_dso);
|
|
goto out_elf_end;
|
|
}
|
|
curr_map->map_ip = identity__map_ip;
|
|
curr_map->unmap_ip = identity__map_ip;
|
|
curr_dso->symtab_type = dso->symtab_type;
|
|
map_groups__insert(kmap->kmaps, curr_map);
|
|
dsos__add(&dso->node, curr_dso);
|
|
dso__set_loaded(curr_dso, map->type);
|
|
} else
|
|
curr_dso = curr_map->dso;
|
|
|
|
goto new_symbol;
|
|
}
|
|
|
|
if (curr_dso->adjust_symbols && 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);
|
|
sym.st_value -= shdr.sh_addr - shdr.sh_offset;
|
|
}
|
|
/*
|
|
* 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...
|
|
*/
|
|
demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
|
|
if (demangled != NULL)
|
|
elf_name = demangled;
|
|
new_symbol:
|
|
f = symbol__new(sym.st_value, sym.st_size,
|
|
GELF_ST_BIND(sym.st_info), elf_name);
|
|
free(demangled);
|
|
if (!f)
|
|
goto out_elf_end;
|
|
|
|
if (filter && filter(curr_map, f))
|
|
symbol__delete(f);
|
|
else {
|
|
symbols__insert(&curr_dso->symbols[curr_map->type], f);
|
|
nr++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* For misannotated, zeroed, ASM function sizes.
|
|
*/
|
|
if (nr > 0) {
|
|
symbols__fixup_duplicate(&dso->symbols[map->type]);
|
|
symbols__fixup_end(&dso->symbols[map->type]);
|
|
if (kmap) {
|
|
/*
|
|
* We need to fixup this here too because we create new
|
|
* maps here, for things like vsyscall sections.
|
|
*/
|
|
__map_groups__fixup_end(kmap->kmaps, map->type);
|
|
}
|
|
}
|
|
err = nr;
|
|
out_elf_end:
|
|
return err;
|
|
}
|
|
|
|
void symbol__elf_init(void)
|
|
{
|
|
elf_version(EV_CURRENT);
|
|
}
|