From c6803cdaba7a7bf933e52cd36f901430253cc2b0 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Mon, 15 Jul 2024 17:27:18 -0700 Subject: libbacktrace: support FDPIC Based on patch by Max Filippov. * internal.h: If FDPIC, #include and/or . (libbacktrace_using_fdpic): Define. (struct libbacktrace_base_address): Define. (libbacktrace_add_base): Define. (backtrace_dwarf_add): Change base_address to struct libbacktrace_base_address. * dwarf.c (struct dwarf_data): Change base_address to struct libbacktrace_base_address. (add_ranges, find_address_ranges, build_ddress_map): Likewise. (build_dwarf_data, build_dwarf_add): Likewise. (add_low_high_range): Change base_address to struct libbacktrace_base_address. Use libbacktrace_add_base. (add_ranges_from_ranges, add_ranges_from_rnglists): Likewise. (add_line): Use libbacktrace_add_base. * elf.c (elf_initialize_syminfo): Change base_address to struct libbacktrace_base_address. Use libbacktrace_add_base. (elf_add): Change base_address to struct libbacktrace_base_address. (phdr_callback): Likewise. Initialize base_address.m. (backtrace_initialize): If using FDPIC, don't call elf_add with main executable; always use dl_iterate_phdr. * macho.c (macho_add_symtab): Change base_address to struct libbacktrace_base_address. Use libbacktrace_add_base. (macho_syminfo): Change base_address to struct libbacktrace_base_address. (macho_add_fat, macho_add_dsym, macho_add): Likewise. (backtrace_initialize): Likewise. Initialize base_address.m. * pecoff.c (coff_initialize_syminfo): Change base_address to struct libbacktrace_base_address. Use libbacktrace_add_base. (coff_add): Change base_address to struct libbacktrace_base_address. Initialize base_address.m. --- libbacktrace/elf.c | 31 ++++++++++++++++++++++--------- 1 file changed, 22 insertions(+), 9 deletions(-) (limited to 'libbacktrace/elf.c') diff --git a/libbacktrace/elf.c b/libbacktrace/elf.c index 107c968..e8d67fe 100644 --- a/libbacktrace/elf.c +++ b/libbacktrace/elf.c @@ -633,7 +633,7 @@ elf_symbol_search (const void *vkey, const void *ventry) static int elf_initialize_syminfo (struct backtrace_state *state, - uintptr_t base_address, + struct libbacktrace_base_address base_address, const unsigned char *symtab_data, size_t symtab_size, const unsigned char *strtab, size_t strtab_size, backtrace_error_callback error_callback, @@ -699,7 +699,8 @@ elf_initialize_syminfo (struct backtrace_state *state, = *(const b_elf_addr *) (opd->data + (sym->st_value - opd->addr)); else elf_symbols[j].address = sym->st_value; - elf_symbols[j].address += base_address; + elf_symbols[j].address = + libbacktrace_add_base (elf_symbols[j].address, base_address); elf_symbols[j].size = sym->st_size; ++j; } @@ -6499,7 +6500,8 @@ backtrace_uncompress_lzma (struct backtrace_state *state, static int elf_add (struct backtrace_state *state, const char *filename, int descriptor, const unsigned char *memory, size_t memory_size, - uintptr_t base_address, struct elf_ppc64_opd_data *caller_opd, + struct libbacktrace_base_address base_address, + struct elf_ppc64_opd_data *caller_opd, backtrace_error_callback error_callback, void *data, fileline *fileline_fn, int *found_sym, int *found_dwarf, struct dwarf_data **fileline_entry, int exe, int debuginfo, @@ -7349,6 +7351,7 @@ phdr_callback (struct dl_phdr_info *info, size_t size ATTRIBUTE_UNUSED, const char *filename; int descriptor; int does_not_exist; + struct libbacktrace_base_address base_address; fileline elf_fileline_fn; int found_dwarf; @@ -7378,7 +7381,8 @@ phdr_callback (struct dl_phdr_info *info, size_t size ATTRIBUTE_UNUSED, return 0; } - if (elf_add (pd->state, filename, descriptor, NULL, 0, info->dlpi_addr, NULL, + base_address.m = info->dlpi_addr; + if (elf_add (pd->state, filename, descriptor, NULL, 0, base_address, NULL, pd->error_callback, pd->data, &elf_fileline_fn, pd->found_sym, &found_dwarf, NULL, 0, 0, NULL, 0)) { @@ -7407,11 +7411,20 @@ backtrace_initialize (struct backtrace_state *state, const char *filename, fileline elf_fileline_fn = elf_nodebug; struct phdr_data pd; - ret = elf_add (state, filename, descriptor, NULL, 0, 0, NULL, error_callback, - data, &elf_fileline_fn, &found_sym, &found_dwarf, NULL, 1, 0, - NULL, 0); - if (!ret) - return 0; + /* When using fdpic we must use dl_iterate_phdr for all modules, including + the main executable, so that we can get the right base address + mapping. */ + if (!libbacktrace_using_fdpic ()) + { + struct libbacktrace_base_address zero_base_address; + + memset (&zero_base_address, 0, sizeof zero_base_address); + ret = elf_add (state, filename, descriptor, NULL, 0, zero_base_address, + NULL, error_callback, data, &elf_fileline_fn, &found_sym, + &found_dwarf, NULL, 1, 0, NULL, 0); + if (!ret) + return 0; + } pd.state = state; pd.error_callback = error_callback; -- cgit v1.1