/*--------------------------------------------------------------------*/ /*--- Reading of syms & debug info from ELF .so/executable files. ---*/ /*--- readelf.c ---*/ /*--------------------------------------------------------------------*/ /* This file is part of Valgrind, a dynamic binary instrumentation framework. Copyright (C) 2000-2013 Julian Seward jseward@acm.org This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. The GNU General Public License is contained in the file COPYING. */ #if defined(VGO_linux) #include "pub_core_basics.h" #include "pub_core_vki.h" #include "pub_core_debuginfo.h" #include "pub_core_libcbase.h" #include "pub_core_libcprint.h" #include "pub_core_libcassert.h" #include "pub_core_machine.h" /* VG_ELF_CLASS */ #include "pub_core_options.h" #include "pub_core_oset.h" #include "pub_core_tooliface.h" /* VG_(needs) */ #include "pub_core_xarray.h" #include "priv_misc.h" /* dinfo_zalloc/free/strdup */ #include "priv_image.h" #include "priv_d3basics.h" #include "priv_tytypes.h" #include "priv_storage.h" #include "priv_readelf.h" /* self */ #include "priv_readdwarf.h" /* 'cos ELF contains DWARF */ #include "priv_readdwarf3.h" #include "priv_readexidx.h" /* --- !!! --- EXTERNAL HEADERS start --- !!! --- */ #include /* --- !!! --- EXTERNAL HEADERS end --- !!! --- */ /*------------------------------------------------------------*/ /*--- 32/64-bit parameterisation ---*/ /*------------------------------------------------------------*/ /* For all the ELF macros and types which specify '32' or '64', select the correct variant for this platform and give it an 'XX' name. Then use the 'XX' variant consistently in the rest of this file. */ #if VG_WORDSIZE == 4 # define ElfXX_Ehdr Elf32_Ehdr # define ElfXX_Shdr Elf32_Shdr # define ElfXX_Phdr Elf32_Phdr # define ElfXX_Nhdr Elf32_Nhdr # define ElfXX_Sym Elf32_Sym # define ElfXX_Off Elf32_Off # define ElfXX_Word Elf32_Word # define ElfXX_Addr Elf32_Addr # define ElfXX_Dyn Elf32_Dyn # define ELFXX_ST_BIND ELF32_ST_BIND # define ELFXX_ST_TYPE ELF32_ST_TYPE #elif VG_WORDSIZE == 8 # define ElfXX_Ehdr Elf64_Ehdr # define ElfXX_Shdr Elf64_Shdr # define ElfXX_Phdr Elf64_Phdr # define ElfXX_Nhdr Elf64_Nhdr # define ElfXX_Sym Elf64_Sym # define ElfXX_Off Elf64_Off # define ElfXX_Word Elf64_Word # define ElfXX_Addr Elf64_Addr # define ElfXX_Dyn Elf64_Dyn # define ELFXX_ST_BIND ELF64_ST_BIND # define ELFXX_ST_TYPE ELF64_ST_TYPE #else # error "VG_WORDSIZE should be 4 or 8" #endif /*------------------------------------------------------------*/ /*--- ---*/ /*--- Read symbol table and line info from ELF files. ---*/ /*--- ---*/ /*------------------------------------------------------------*/ /* readelf.c parses ELF files and acquires symbol table info from them. It calls onwards to readdwarf.c to read DWARF2/3 line number and call frame info found. */ /* Identify an ELF object file by peering at the first few bytes of it. */ Bool ML_(is_elf_object_file)( const void* image, SizeT n_image, Bool rel_ok ) { const ElfXX_Ehdr* ehdr = image; Int ok = 1; if (n_image < sizeof(ElfXX_Ehdr)) return False; ok &= (ehdr->e_ident[EI_MAG0] == 0x7F && ehdr->e_ident[EI_MAG1] == 'E' && ehdr->e_ident[EI_MAG2] == 'L' && ehdr->e_ident[EI_MAG3] == 'F'); ok &= (ehdr->e_ident[EI_CLASS] == VG_ELF_CLASS && ehdr->e_ident[EI_DATA] == VG_ELF_DATA2XXX && ehdr->e_ident[EI_VERSION] == EV_CURRENT); ok &= (ehdr->e_type == ET_EXEC || ehdr->e_type == ET_DYN || (rel_ok && ehdr->e_type == ET_REL)); ok &= (ehdr->e_machine == VG_ELF_MACHINE); ok &= (ehdr->e_version == EV_CURRENT); ok &= (ehdr->e_shstrndx != SHN_UNDEF); ok &= (ehdr->e_shoff != 0 && ehdr->e_shnum != 0); ok &= ((ehdr->e_phoff != 0 && ehdr->e_phnum != 0) || ehdr->e_type == ET_REL); return ok ? True : False; } /* The same thing, but operating on a DiImage instead. */ static Bool is_elf_object_file_by_DiImage( DiImage* img, Bool rel_ok ) { /* Be sure this doesn't make the frame too big. */ vg_assert(sizeof(ElfXX_Ehdr) <= 512); ElfXX_Ehdr ehdr; if (!ML_(img_valid)(img, 0, sizeof(ehdr))) return False; ML_(img_get)(&ehdr, img, 0, sizeof(ehdr)); return ML_(is_elf_object_file)( &ehdr, sizeof(ehdr), rel_ok ); } /* Show a raw ELF symbol, given its in-image address and name. */ static void show_raw_elf_symbol ( DiImage* strtab_img, Int i, const ElfXX_Sym* sym, DiOffT sym_name_ioff, Addr sym_svma, Bool ppc64_linux_format ) { const HChar* space = ppc64_linux_format ? " " : ""; VG_(printf)("raw symbol [%4d]: ", i); switch (ELFXX_ST_BIND(sym->st_info)) { case STB_LOCAL: VG_(printf)("LOC "); break; case STB_GLOBAL: VG_(printf)("GLO "); break; case STB_WEAK: VG_(printf)("WEA "); break; case STB_LOPROC: VG_(printf)("lop "); break; case STB_HIPROC: VG_(printf)("hip "); break; default: VG_(printf)("??? "); break; } switch (ELFXX_ST_TYPE(sym->st_info)) { case STT_NOTYPE: VG_(printf)("NOT "); break; case STT_OBJECT: VG_(printf)("OBJ "); break; case STT_FUNC: VG_(printf)("FUN "); break; case STT_SECTION: VG_(printf)("SEC "); break; case STT_FILE: VG_(printf)("FIL "); break; case STT_LOPROC: VG_(printf)("lop "); break; case STT_HIPROC: VG_(printf)("hip "); break; default: VG_(printf)("??? "); break; } HChar* sym_name = NULL; if (sym->st_name) sym_name = ML_(img_strdup)(strtab_img, "di.sres.1", sym_name_ioff); VG_(printf)(": svma %#010lx, %ssz %4llu %s\n", sym_svma, space, (ULong)(sym->st_size + 0UL), (sym_name ? sym_name : "NONAME") ); if (sym_name) ML_(dinfo_free)(sym_name); } /* Decide whether SYM is something we should collect, and if so, copy relevant info to the _OUT arguments. For {x86,amd64,ppc32}-linux this is straightforward - the name, address, size are copied out unchanged. There is a bit of a kludge re data symbols (see KLUDGED BSS CHECK below): we assume that the .bss is mapped immediately after .data, and so accept any data symbol which exists in the range [start of .data, size of .data + size of .bss). I don't know if this is really correct/justifiable, or not. For ppc64be-linux it's more complex. If the symbol is seen to be in the .opd section, it is taken to be a function descriptor, and so a dereference is attempted, in order to get hold of the real entry point address. Also as part of the dereference, there is an attempt to calculate the TOC pointer (R2 value) associated with the symbol. To support the ppc64be-linux pre-"dotless" ABI (prior to gcc 4.0.0), if the symbol is seen to be outside the .opd section and its name starts with a dot, an .opd deference is not attempted, and no TOC pointer is calculated, but the leading dot is removed from the name. As a result, on ppc64be-linux, the caller of this function may have to piece together the real size, address, name of the symbol from multiple calls to this function. Ugly and confusing. */ static Bool get_elf_symbol_info ( /* INPUTS */ struct _DebugInfo* di, /* containing DebugInfo */ const ElfXX_Sym* sym, /* ELF symbol */ DiOffT sym_name_ioff, /* name, may be absent (DiOffT_INVALID) */ const DiSlice* escn_strtab, /* holds the name */ Addr sym_svma, /* address as stated in the object file */ Bool symtab_in_debug, /* symbol table is in the debug file */ const DiSlice* escn_opd, /* the .opd (ppc64be-linux only) */ PtrdiffT opd_bias, /* for biasing AVMAs found in .opd */ /* OUTPUTS */ DiOffT* sym_name_out_ioff, /* name (in strtab) we should record */ SymAVMAs* sym_avmas_out, /* sym avmas we should record */ Int* sym_size_out, /* symbol size */ Bool* from_opd_out, /* ppc64be-linux only: did we deref an .opd entry? */ Bool* is_text_out, /* is this a text symbol? */ Bool* is_ifunc /* is this a STT_GNU_IFUNC function ?*/ ) { Bool plausible; # if defined(VGP_ppc64be_linux) Bool is_in_opd; # endif Bool in_text, in_data, in_sdata, in_rodata, in_bss, in_sbss; Addr text_svma, data_svma, sdata_svma, rodata_svma, bss_svma, sbss_svma; PtrdiffT text_bias, data_bias, sdata_bias, rodata_bias, bss_bias, sbss_bias; /* Set defaults */ *sym_name_out_ioff = sym_name_ioff; (*sym_avmas_out).main = sym_svma; /* we will bias this shortly */ *is_text_out = True; SET_TOCPTR_AVMA(*sym_avmas_out, 0); /* default to unknown/inapplicable */ SET_LOCAL_EP_AVMA(*sym_avmas_out, 0); /* default to unknown/inapplicable */ *from_opd_out = False; *is_ifunc = False; /* Get the symbol size, but restrict it to fit in a signed 32 bit int. Also, deal with the stupid case of negative size by making the size be 1. Note that sym->st_size has type UWord, effectively. */ { Word size_tmp = (Word)sym->st_size; Word max_Int = (1LL << 31) - 1; if (size_tmp < 0) size_tmp = 1; if (size_tmp > max_Int) size_tmp = max_Int; *sym_size_out = (Int)size_tmp; } /* After this point refer only to *sym_size_out and not to sym->st_size. */ /* Figure out if we're interested in the symbol. Firstly, is it of the right flavour? */ plausible = (ELFXX_ST_BIND(sym->st_info) == STB_GLOBAL || ELFXX_ST_BIND(sym->st_info) == STB_LOCAL || ELFXX_ST_BIND(sym->st_info) == STB_WEAK ) && (ELFXX_ST_TYPE(sym->st_info) == STT_FUNC || ELFXX_ST_TYPE(sym->st_info) == STT_OBJECT # ifdef STT_GNU_IFUNC || ELFXX_ST_TYPE(sym->st_info) == STT_GNU_IFUNC # endif ); /* Work out the svma and bias for each section as it will appear in addresses in the symbol table. */ if (symtab_in_debug) { text_svma = di->text_debug_svma; text_bias = di->text_debug_bias; data_svma = di->data_debug_svma; data_bias = di->data_debug_bias; sdata_svma = di->sdata_debug_svma; sdata_bias = di->sdata_debug_bias; rodata_svma = di->rodata_debug_svma; rodata_bias = di->rodata_debug_bias; bss_svma = di->bss_debug_svma; bss_bias = di->bss_debug_bias; sbss_svma = di->sbss_debug_svma; sbss_bias = di->sbss_debug_bias; } else { text_svma = di->text_svma; text_bias = di->text_bias; data_svma = di->data_svma; data_bias = di->data_bias; sdata_svma = di->sdata_svma; sdata_bias = di->sdata_bias; rodata_svma = di->rodata_svma; rodata_bias = di->rodata_bias; bss_svma = di->bss_svma; bss_bias = di->bss_bias; sbss_svma = di->sbss_svma; sbss_bias = di->sbss_bias; } /* Now bias (*sym_avmas_out).main accordingly by figuring out exactly which section the symbol is from and bias accordingly. Screws up if the previously deduced section svma address ranges are wrong. */ if (di->text_present && di->text_size > 0 && sym_svma >= text_svma && sym_svma < text_svma + di->text_size) { *is_text_out = True; (*sym_avmas_out).main += text_bias; } else if (di->data_present && di->data_size > 0 && sym_svma >= data_svma && sym_svma < data_svma + di->data_size) { *is_text_out = False; (*sym_avmas_out).main += data_bias; } else if (di->sdata_present && di->sdata_size > 0 && sym_svma >= sdata_svma && sym_svma < sdata_svma + di->sdata_size) { *is_text_out = False; (*sym_avmas_out).main += sdata_bias; } else if (di->rodata_present && di->rodata_size > 0 && sym_svma >= rodata_svma && sym_svma < rodata_svma + di->rodata_size) { *is_text_out = False; (*sym_avmas_out).main += rodata_bias; } else if (di->bss_present && di->bss_size > 0 && sym_svma >= bss_svma && sym_svma < bss_svma + di->bss_size) { *is_text_out = False; (*sym_avmas_out).main += bss_bias; } else if (di->sbss_present && di->sbss_size > 0 && sym_svma >= sbss_svma && sym_svma < sbss_svma + di->sbss_size) { *is_text_out = False; (*sym_avmas_out).main += sbss_bias; } else { /* Assume it's in .text. Is this a good idea? */ *is_text_out = True; (*sym_avmas_out).main += text_bias; } # ifdef STT_GNU_IFUNC /* Check for indirect functions. */ if (*is_text_out && ELFXX_ST_TYPE(sym->st_info) == STT_GNU_IFUNC) { *is_ifunc = True; } # endif # if defined(VGP_ppc64be_linux) /* Allow STT_NOTYPE in the very special case where we're running on ppc64be-linux and the symbol is one which the .opd-chasing hack below will chase. */ if (!plausible && *is_text_out && ELFXX_ST_TYPE(sym->st_info) == STT_NOTYPE && *sym_size_out > 0 && di->opd_present && di->opd_size > 0 && (*sym_avmas_out).main >= di->opd_avma && (*sym_avmas_out).main < di->opd_avma + di->opd_size) plausible = True; # endif if (!plausible) return False; /* Ignore if nameless. */ if (sym_name_ioff == DiOffT_INVALID || /* VG_(strlen)(sym_name) == 0 */ /* equivalent but cheaper ... */ ML_(img_get_UChar)(escn_strtab->img, sym_name_ioff) == '\0') { if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.1", sym_name_ioff); TRACE_SYMTAB(" ignore -- nameless: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; } /* Ignore if zero-sized. Except on Android: On Android 2.3.5, some of the symbols that Memcheck needs to intercept (for noise reduction purposes) have zero size, due to lack of .size directives in handwritten assembly sources. So we can't reject them out of hand -- instead give them a bogusly large size and let canonicaliseSymtab trim them so they don't overlap any following symbols. At least the following symbols are known to be affected: in /system/lib/libc.so: strlen strcmp strcpy memcmp memcpy in /system/bin/linker: __dl_strcmp __dl_strlen */ if (*sym_size_out == 0) { # if defined(VGPV_arm_linux_android) \ || defined(VGPV_x86_linux_android) \ || defined(VGPV_mips32_linux_android) \ || defined(VGPV_arm64_linux_android) *sym_size_out = 2048; # else if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.2", sym_name_ioff); TRACE_SYMTAB(" ignore -- size=0: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; # endif } /* This seems to significantly reduce the number of junk symbols, and particularly reduces the number of overlapping address ranges. Don't ask me why ... */ if ((Int)sym->st_value == 0) { if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.3", sym_name_ioff); TRACE_SYMTAB( " ignore -- valu=0: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; } /* If it's apparently in a GOT or PLT, it's really a reference to a symbol defined elsewhere, so ignore it. */ if (di->got_present && di->got_size > 0 && (*sym_avmas_out).main >= di->got_avma && (*sym_avmas_out).main < di->got_avma + di->got_size) { if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.4", sym_name_ioff); TRACE_SYMTAB(" ignore -- in GOT: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; } if (di->plt_present && di->plt_size > 0 && (*sym_avmas_out).main >= di->plt_avma && (*sym_avmas_out).main < di->plt_avma + di->plt_size) { if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.5", sym_name_ioff); TRACE_SYMTAB(" ignore -- in PLT: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; } /* ppc64be-linux nasty hack: if the symbol is in an .opd section, then really what we have is the address of a function descriptor. So use the first word of that as the function's text. See thread starting at http://gcc.gnu.org/ml/gcc-patches/2004-08/msg00557.html */ # if defined(VGP_ppc64be_linux) /* Host and guest may have different Endianess, used by BE only */ is_in_opd = False; # endif if (di->opd_present && di->opd_size > 0 && (*sym_avmas_out).main >= di->opd_avma && (*sym_avmas_out).main < di->opd_avma + di->opd_size) { # if !defined(VGP_ppc64be_linux) if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.6", sym_name_ioff); TRACE_SYMTAB(" ignore -- in OPD: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; # else Int offset_in_opd; Bool details = 1||False; if (details) TRACE_SYMTAB("opdXXX: opd_bias %p, sym_svma_out %p\n", (void*)(opd_bias), (void*)(*sym_avmas_out).main); if (!VG_IS_8_ALIGNED((*sym_avmas_out).main)) { if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.6a", sym_name_ioff); TRACE_SYMTAB(" ignore -- not 8-aligned: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; } /* (*sym_avmas_out).main is a avma pointing into the .opd section. We know the vma of the opd section start, so we can figure out how far into the opd section this is. */ offset_in_opd = (Addr)(*sym_avmas_out).main - (Addr)(di->opd_avma); if (offset_in_opd < 0 || offset_in_opd >= di->opd_size) { if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.6a", sym_name_ioff); TRACE_SYMTAB(" ignore -- invalid OPD offset: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; } /* Now we want to know what's at that offset in the .opd section. We can't look in the running image since it won't necessarily have been mapped. But we can consult the oimage. opd_img is the start address of the .opd in the oimage. Hence: */ ULong fn_descr[2]; /* is actually 3 words, but we need only 2 */ if (!ML_(img_valid)(escn_opd->img, escn_opd->ioff + offset_in_opd, sizeof(fn_descr))) { if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.6b", sym_name_ioff); TRACE_SYMTAB(" ignore -- invalid OPD fn_descr offset: %s\n", sym_name); if (sym_name) ML_(dinfo_free)(sym_name); } return False; } /* This can't fail now, because we just checked the offset above. */ ML_(img_get)(&fn_descr[0], escn_opd->img, escn_opd->ioff + offset_in_opd, sizeof(fn_descr)); if (details) TRACE_SYMTAB("opdXXY: offset %d, fn_descr %p\n", offset_in_opd, fn_descr); if (details) TRACE_SYMTAB("opdXXZ: *fn_descr %p\n", (void*)(fn_descr[0])); /* opd_bias is the what we have to add to SVMAs found in .opd to get plausible .text AVMAs for the entry point, and .data AVMAs (presumably) for the TOC locations. We use the caller supplied value (which is di->text_bias) for both of these. Not sure why that is correct - it seems to work, and sounds OK for fn_descr[0], but surely we need to use the data bias and not the text bias for fn_descr[1] ? Oh Well. */ (*sym_avmas_out).main = fn_descr[0] + opd_bias; SET_TOCPTR_AVMA(*sym_avmas_out, fn_descr[1] + opd_bias); *from_opd_out = True; is_in_opd = True; /* Do a final sanity check: if the symbol falls outside the DebugInfo's mapped range, ignore it. Since (*sym_avmas_out).main has been updated, that can be achieved simply by falling through to the test below. */ # endif /* ppc64-linux nasty hack */ } /* Here's yet another ppc64-linux hack. Get rid of leading dot if the symbol is outside .opd. */ # if defined(VGP_ppc64be_linux) if (di->opd_size > 0 && !is_in_opd && *sym_name_out_ioff != DiOffT_INVALID && ML_(img_get_UChar)(escn_strtab->img, *sym_name_out_ioff) == '.') { vg_assert(!(*from_opd_out)); (*sym_name_out_ioff)++; } # endif /* If no part of the symbol falls within the mapped range, ignore it. */ in_text = di->text_present && di->text_size > 0 && !((*sym_avmas_out).main + *sym_size_out <= di->text_avma || (*sym_avmas_out).main >= di->text_avma + di->text_size); in_data = di->data_present && di->data_size > 0 && !((*sym_avmas_out).main + *sym_size_out <= di->data_avma || (*sym_avmas_out).main >= di->data_avma + di->data_size); in_sdata = di->sdata_present && di->sdata_size > 0 && !((*sym_avmas_out).main + *sym_size_out <= di->sdata_avma || (*sym_avmas_out).main >= di->sdata_avma + di->sdata_size); in_rodata = di->rodata_present && di->rodata_size > 0 && !((*sym_avmas_out).main + *sym_size_out <= di->rodata_avma || (*sym_avmas_out).main >= di->rodata_avma + di->rodata_size); in_bss = di->bss_present && di->bss_size > 0 && !((*sym_avmas_out).main + *sym_size_out <= di->bss_avma || (*sym_avmas_out).main >= di->bss_avma + di->bss_size); in_sbss = di->sbss_present && di->sbss_size > 0 && !((*sym_avmas_out).main + *sym_size_out <= di->sbss_avma || (*sym_avmas_out).main >= di->sbss_avma + di->sbss_size); if (*is_text_out) { /* This used to reject any symbol falling outside the text segment ("if (!in_text) ..."). Now it is relaxed slightly, to reject only symbols which fall outside the area mapped r-x. This is in accordance with r7427. See "Comment_Regarding_Text_Range_Checks" in storage.c for background. */ Bool in_rx; vg_assert(di->fsm.have_rx_map); /* This could actually wrap around and cause ML_(find_rx_mapping) to assert. But that seems so unlikely, let's wait for it to happen before fixing it. */ in_rx = (ML_(find_rx_mapping)( di, (*sym_avmas_out).main, (*sym_avmas_out).main + *sym_size_out) != NULL); if (in_text) vg_assert(in_rx); if (!in_rx) { TRACE_SYMTAB( "ignore -- %#lx .. %#lx outside .text svma range %#lx .. %#lx\n", (*sym_avmas_out).main, (*sym_avmas_out).main + *sym_size_out, di->text_avma, di->text_avma + di->text_size); return False; } } else { if (!(in_data || in_sdata || in_rodata || in_bss || in_sbss)) { TRACE_SYMTAB( "ignore -- %#lx .. %#lx outside .data / .sdata / .rodata " "/ .bss / .sbss svma ranges\n", (*sym_avmas_out).main, (*sym_avmas_out).main + *sym_size_out); return False; } } # if defined(VGP_ppc64be_linux) if (di->opd_present && di->opd_size > 0) { vg_assert((*sym_avmas_out).main + *sym_size_out <= di->opd_avma || (*sym_avmas_out).main >= di->opd_avma + di->opd_size); } #endif # if defined(VGP_ppc64le_linux) /* PPC64 LE ABI uses three bits in the st_other field to indicate the number * of instructions between the function's global and local entry points. An * offset of 0 indicates that there is one entry point. The value must be: * * 0 - one entry point, local and global are the same * 1 - reserved * 2 - local entry point is one instruction after the global entry point * 3 - local entry point is two instructions after the global entry point * 4 - local entry point is four instructions after the global entry point * 5 - local entry point is eight instructions after the global entry point * 6 - local entry point is sixteen instructions after the global entry point * 7 - reserved * * Extract the three bit field from the other field is done by: * (other_field & STO_PPC64_LOCAL_MASK) >> STO_PPC_LOCAL_BIT * * where the #define values are given in include/elf/powerpc.h file for * the PPC binutils. * * conversion of the three bit field to bytes is given by * * ((1 << bit_field) >> 2) << 2 */ #define STO_PPC64_LOCAL_BIT 5 #define STO_PPC64_LOCAL_MASK (7 << STO_PPC64_LOCAL_BIT) { unsigned int bit_field, dist_to_local_entry; /* extract the other filed */ bit_field = (sym->st_other & STO_PPC64_LOCAL_MASK) >> STO_PPC64_LOCAL_BIT; if ((bit_field > 0) && (bit_field < 7)) { /* store the local entry point address */ dist_to_local_entry = ((1 << bit_field) >> 2) << 2; SET_LOCAL_EP_AVMA(*sym_avmas_out, (*sym_avmas_out).main + dist_to_local_entry); if (TRACE_SYMTAB_ENABLED) { HChar* sym_name = ML_(img_strdup)(escn_strtab->img, "di.gesi.5", sym_name_ioff); VG_(printf)("Local entry point: %s at %#010x\n", sym_name, (unsigned int)GET_LOCAL_EP_AVMA(*sym_avmas_out)); } } } # endif /* Acquire! */ return True; } /* Read an ELF symbol table (normal or dynamic). This one is for the "normal" case ({x86,amd64,ppc32,arm,mips32,mips64, ppc64le}-linux). */ static __attribute__((unused)) /* not referred to on all targets */ void read_elf_symtab__normal( struct _DebugInfo* di, const HChar* tab_name, DiSlice* escn_symtab, DiSlice* escn_strtab, DiSlice* escn_opd, /* ppc64be-linux only */ Bool symtab_in_debug ) { if (escn_strtab->img == NULL || escn_symtab->img == NULL) { HChar buf[VG_(strlen)(tab_name) + 40]; VG_(sprintf)(buf, " object doesn't have a %s", tab_name); ML_(symerr)(di, False, buf); return; } TRACE_SYMTAB("\n--- Reading (ELF, standard) %s (%lld entries) ---\n", tab_name, escn_symtab->szB/sizeof(ElfXX_Sym) ); /* Perhaps should start at i = 1; ELF docs suggest that entry 0 always denotes 'unknown symbol'. */ Word i; for (i = 1; i < (Word)(escn_symtab->szB/sizeof(ElfXX_Sym)); i++) { ElfXX_Sym sym; ML_(img_get)(&sym, escn_symtab->img, escn_symtab->ioff + i * sizeof(ElfXX_Sym), sizeof(sym)); DiOffT sym_name = escn_strtab->ioff + sym.st_name; Addr sym_svma = sym.st_value; if (di->trace_symtab) show_raw_elf_symbol(escn_strtab->img, i, &sym, sym_name, sym_svma, False); SymAVMAs sym_avmas_really; Int sym_size = 0; Bool from_opd = False, is_text = False, is_ifunc = False; DiOffT sym_name_really = DiOffT_INVALID; sym_avmas_really.main = 0; SET_TOCPTR_AVMA(sym_avmas_really, 0); SET_LOCAL_EP_AVMA(sym_avmas_really, 0); if (get_elf_symbol_info(di, &sym, sym_name, escn_strtab, sym_svma, symtab_in_debug, escn_opd, di->text_bias, &sym_name_really, &sym_avmas_really, &sym_size, &from_opd, &is_text, &is_ifunc)) { DiSym disym; VG_(memset)(&disym, 0, sizeof(disym)); HChar* cstr = ML_(img_strdup)(escn_strtab->img, "di.res__n.1", sym_name_really); disym.avmas = sym_avmas_really; disym.pri_name = ML_(addStr) ( di, cstr, -1 ); disym.sec_names = NULL; disym.size = sym_size; disym.isText = is_text; disym.isIFunc = is_ifunc; if (cstr) { ML_(dinfo_free)(cstr); cstr = NULL; } vg_assert(disym.pri_name); vg_assert(GET_TOCPTR_AVMA(disym.avmas) == 0); /* has no role except on ppc64be-linux */ ML_(addSym) ( di, &disym ); if (TRACE_SYMTAB_ENABLED) { TRACE_SYMTAB(" rec(%c) [%4ld]: " " val %#010lx, sz %4d %s\n", is_text ? 't' : 'd', i, disym.avmas.main, (Int)disym.size, disym.pri_name ); if (GET_LOCAL_EP_AVMA(disym.avmas) != 0) { TRACE_SYMTAB(" local entry point %#010lx\n", GET_LOCAL_EP_AVMA(disym.avmas)); } } } } } /* Read an ELF symbol table (normal or dynamic). This one is for ppc64be-linux, which requires special treatment. */ typedef struct { Addr addr; DiOffT name; /* We have to store also the DiImage* so as to give context for |name|. This is not part of the key (in terms of lookup) but there's no easy other way to do this. Ugly. */ DiImage* img; } TempSymKey; typedef struct { TempSymKey key; Addr tocptr; Int size; Bool from_opd; Bool is_text; Bool is_ifunc; } TempSym; static Word cmp_TempSymKey ( const TempSymKey* key1, const TempSym* elem2 ) { /* Stay sane ... */ vg_assert(key1->img == elem2->key.img); vg_assert(key1->img != NULL); if (key1->addr < elem2->key.addr) return -1; if (key1->addr > elem2->key.addr) return 1; vg_assert(key1->name != DiOffT_INVALID); vg_assert(elem2->key.name != DiOffT_INVALID); return (Word)ML_(img_strcmp)(key1->img, key1->name, elem2->key.name); } static __attribute__((unused)) /* not referred to on all targets */ void read_elf_symtab__ppc64be_linux( struct _DebugInfo* di, const HChar* tab_name, DiSlice* escn_symtab, DiSlice* escn_strtab, DiSlice* escn_opd, /* ppc64be-linux only */ Bool symtab_in_debug ) { Word i; Int old_size; Bool modify_size, modify_tocptr; OSet *oset; TempSymKey key; TempSym *elem; TempSym *prev; if (escn_strtab->img == NULL || escn_symtab->img == NULL) { HChar buf[VG_(strlen)(tab_name) + 40]; VG_(sprintf)(buf, " object doesn't have a %s", tab_name); ML_(symerr)(di, False, buf); return; } TRACE_SYMTAB("\n--- Reading (ELF, ppc64be-linux) %s (%lld entries) ---\n", tab_name, escn_symtab->szB/sizeof(ElfXX_Sym) ); oset = VG_(OSetGen_Create)( offsetof(TempSym,key), (OSetCmp_t)cmp_TempSymKey, ML_(dinfo_zalloc), "di.respl.1", ML_(dinfo_free) ); /* Perhaps should start at i = 1; ELF docs suggest that entry 0 always denotes 'unknown symbol'. */ for (i = 1; i < (Word)(escn_symtab->szB/sizeof(ElfXX_Sym)); i++) { ElfXX_Sym sym; ML_(img_get)(&sym, escn_symtab->img, escn_symtab->ioff + i * sizeof(ElfXX_Sym), sizeof(sym)); DiOffT sym_name = escn_strtab->ioff + sym.st_name; Addr sym_svma = sym.st_value; if (di->trace_symtab) show_raw_elf_symbol(escn_strtab->img, i, &sym, sym_name, sym_svma, True); SymAVMAs sym_avmas_really; Int sym_size = 0; Bool from_opd = False, is_text = False, is_ifunc = False; DiOffT sym_name_really = DiOffT_INVALID; DiSym disym; VG_(memset)(&disym, 0, sizeof(disym)); sym_avmas_really.main = 0; SET_TOCPTR_AVMA(sym_avmas_really, 0); SET_LOCAL_EP_AVMA(sym_avmas_really, 0); if (get_elf_symbol_info(di, &sym, sym_name, escn_strtab, sym_svma, symtab_in_debug, escn_opd, di->text_bias, &sym_name_really, &sym_avmas_really, &sym_size, &from_opd, &is_text, &is_ifunc)) { /* Check if we've seen this (name,addr) key before. */ key.addr = sym_avmas_really.main; key.name = sym_name_really; key.img = escn_strtab->img; prev = VG_(OSetGen_Lookup)( oset, &key ); if (prev) { /* Seen it before. Fold in whatever new info we can. */ modify_size = False; modify_tocptr = False; old_size = 0; if (prev->from_opd && !from_opd && (prev->size == 24 || prev->size == 16) && sym_size != prev->size) { /* Existing one is an opd-redirect, with a bogus size, so the only useful new fact we have is the real size of the symbol. */ modify_size = True; old_size = prev->size; prev->size = sym_size; } else if (!prev->from_opd && from_opd && (sym_size == 24 || sym_size == 16)) { /* Existing one is non-opd, new one is opd. What we can acquire from the new one is the TOC ptr to be used. Since the existing sym is non-toc, it shouldn't currently have an known TOC ptr. */ vg_assert(prev->tocptr == 0); modify_tocptr = True; prev->tocptr = GET_TOCPTR_AVMA(sym_avmas_really); } else { /* ignore. can we do better here? */ } /* Only one or the other is possible (I think) */ vg_assert(!(modify_size && modify_tocptr)); if (modify_size && di->trace_symtab) { VG_(printf)(" modify (old sz %4d) " " val %#010lx, toc %#010lx, sz %4d %lld\n", old_size, prev->key.addr, prev->tocptr, (Int) prev->size, (ULong)prev->key.name ); } if (modify_tocptr && di->trace_symtab) { VG_(printf)(" modify (upd tocptr) " " val %#010lx, toc %#010lx, sz %4d %lld\n", prev->key.addr, prev->tocptr, (Int) prev->size, (ULong)prev->key.name ); } } else { /* A new (name,addr) key. Add and continue. */ elem = VG_(OSetGen_AllocNode)(oset, sizeof(TempSym)); elem->key = key; elem->tocptr = GET_TOCPTR_AVMA(sym_avmas_really); elem->size = sym_size; elem->from_opd = from_opd; elem->is_text = is_text; elem->is_ifunc = is_ifunc; VG_(OSetGen_Insert)(oset, elem); if (di->trace_symtab) { HChar* str = ML_(img_strdup)(escn_strtab->img, "di.respl.2", elem->key.name); VG_(printf)(" to-oset [%4ld]: " " val %#010lx, toc %#010lx, sz %4d %s\n", i, elem->key.addr, elem->tocptr, (Int) elem->size, str ); if (str) ML_(dinfo_free)(str); } } } } /* All the syms that matter are in the oset. Now pull them out, build a "standard" symbol table, and nuke the oset. */ i = 0; VG_(OSetGen_ResetIter)( oset ); while ( (elem = VG_(OSetGen_Next)(oset)) ) { DiSym disym; VG_(memset)(&disym, 0, sizeof(disym)); HChar* cstr = ML_(img_strdup)(escn_strtab->img, "di.res__ppc64.1", elem->key.name); disym.avmas.main = elem->key.addr; SET_TOCPTR_AVMA(disym.avmas, elem->tocptr); SET_LOCAL_EP_AVMA(disym.avmas, 0); // ppc64be does not use local_ep. disym.pri_name = ML_(addStr) ( di, cstr, -1 ); disym.sec_names = NULL; disym.size = elem->size; disym.isText = elem->is_text; disym.isIFunc = elem->is_ifunc; if (cstr) { ML_(dinfo_free)(cstr); cstr = NULL; } vg_assert(disym.pri_name != NULL); ML_(addSym) ( di, &disym ); if (di->trace_symtab) { VG_(printf)(" rec(%c) [%4ld]: " " val %#010lx, toc %#010lx, sz %4d %s\n", disym.isText ? 't' : 'd', i, disym.avmas.main, GET_TOCPTR_AVMA(disym.avmas), (Int) disym.size, disym.pri_name ); } i++; } VG_(OSetGen_Destroy)( oset ); } /* * Look for a build-id in an ELF image. The build-id specification * can be found here: * * http://fedoraproject.org/wiki/RolandMcGrath/BuildID * * Returned string must be freed by the caller. */ static HChar* find_buildid(DiImage* img, Bool rel_ok, Bool search_shdrs) { HChar* buildid = NULL; # ifdef NT_GNU_BUILD_ID if (is_elf_object_file_by_DiImage(img, rel_ok)) { Word i; ElfXX_Ehdr ehdr; ML_(img_get)(&ehdr, img, 0, sizeof(ehdr)); for (i = 0; i < ehdr.e_phnum; i++) { ElfXX_Phdr phdr; ML_(img_get)(&phdr, img, ehdr.e_phoff + i * ehdr.e_phentsize, sizeof(phdr)); if (phdr.p_type == PT_NOTE) { ElfXX_Off note_ioff = phdr.p_offset; while (note_ioff < phdr.p_offset + phdr.p_filesz) { ElfXX_Nhdr note; ML_(img_get)(¬e, img, (DiOffT)note_ioff, sizeof(note)); DiOffT name_ioff = note_ioff + sizeof(ElfXX_Nhdr); DiOffT desc_ioff = name_ioff + ((note.n_namesz + 3) & ~3); if (ML_(img_strcmp_c)(img, name_ioff, ELF_NOTE_GNU) == 0 && note.n_type == NT_GNU_BUILD_ID) { buildid = ML_(dinfo_zalloc)("di.fbi.1", note.n_descsz * 2 + 1); Word j; for (j = 0; j < note.n_descsz; j++) { UChar desc_j = ML_(img_get_UChar)(img, desc_ioff + j); VG_(sprintf)(buildid + VG_(strlen)(buildid), "%02x", (UInt)desc_j); } } note_ioff = note_ioff + sizeof(ElfXX_Nhdr) + ((note.n_namesz + 3) & ~3) + ((note.n_descsz + 3) & ~3); } } } /* Normally we would only search shdrs for ET_REL files, but when we search for a separate .debug file phdrs might not be there (they are never loaded) or have been corrupted, so try again against shdrs. */ if (buildid || (!rel_ok && !search_shdrs)) return buildid; for (i = 0; i < ehdr.e_shnum; i++) { ElfXX_Shdr shdr; ML_(img_get)(&shdr, img, ehdr.e_shoff + i * ehdr.e_shentsize, sizeof(shdr)); if (shdr.sh_type == SHT_NOTE) { ElfXX_Off note_ioff = shdr.sh_offset; while (note_ioff < shdr.sh_offset + shdr.sh_size) { ElfXX_Nhdr note; ML_(img_get)(¬e, img, (DiOffT)note_ioff, sizeof(note)); DiOffT name_ioff = note_ioff + sizeof(ElfXX_Nhdr); DiOffT desc_ioff = name_ioff + ((note.n_namesz + 3) & ~3); if (ML_(img_strcmp_c)(img, name_ioff, ELF_NOTE_GNU) == 0 && note.n_type == NT_GNU_BUILD_ID) { buildid = ML_(dinfo_zalloc)("di.fbi.2", note.n_descsz * 2 + 1); Word j; for (j = 0; j < note.n_descsz; j++) { UChar desc_j = ML_(img_get_UChar)(img, desc_ioff + j); VG_(sprintf)(buildid + VG_(strlen)(buildid), "%02x", (UInt)desc_j); } } note_ioff = note_ioff + sizeof(ElfXX_Nhdr) + ((note.n_namesz + 3) & ~3) + ((note.n_descsz + 3) & ~3); } } } } # endif /* def NT_GNU_BUILD_ID */ return buildid; } /* Try and open a separate debug file, ignoring any where the CRC does not match the value from the main object file. Returned DiImage must be discarded by the caller. If |serverAddr| is NULL, |name| is expected to be a fully qualified (absolute) path to the file in the local filesystem. If |serverAddr| is non-NULL, it is expected to be an IPv4 and port spec of the form "d.d.d.d:d" or "d.d.d.d", and |name| is expected to be a plain filename (no path components at all). */ static DiImage* open_debug_file( const HChar* name, const HChar* buildid, UInt crc, Bool rel_ok, const HChar* serverAddr ) { DiImage* dimg = serverAddr ? ML_(img_from_di_server)(name, serverAddr) : ML_(img_from_local_file)(name); if (dimg == NULL) return NULL; if (VG_(clo_verbosity) > 1) { if (serverAddr) VG_(message)(Vg_DebugMsg, " Considering %s on server %s ..\n", name, serverAddr); else VG_(message)(Vg_DebugMsg, " Considering %s ..\n", name); } /* We will always check the crc if we have one (altfiles don't have one) for now because we might be opening the main file again by any other name, and that obviously also has the same buildid. More efficient would be an fstat bases check or a check that the file actually contains .debug* sections. */ if (buildid && crc == 0) { HChar* debug_buildid = find_buildid(dimg, rel_ok, True); if (debug_buildid == NULL || VG_(strcmp)(buildid, debug_buildid) != 0) { ML_(img_done)(dimg); if (VG_(clo_verbosity) > 1) VG_(message)(Vg_DebugMsg, " .. build-id mismatch (found %s wanted %s)\n", debug_buildid, buildid); ML_(dinfo_free)(debug_buildid); return NULL; } ML_(dinfo_free)(debug_buildid); if (VG_(clo_verbosity) > 1) VG_(message)(Vg_DebugMsg, " .. build-id is valid\n"); } else { UInt calccrc = ML_(img_calc_gnu_debuglink_crc32)(dimg); if (calccrc != crc) { ML_(img_done)(dimg); if (VG_(clo_verbosity) > 1) VG_(message)(Vg_DebugMsg, " .. CRC mismatch (computed %08x wanted %08x)\n", calccrc, crc); return NULL; } if (VG_(clo_verbosity) > 1) VG_(message)(Vg_DebugMsg, " .. CRC is valid\n"); } return dimg; } /* Try to find a separate debug file for a given object file. If found, return its DiImage, which should be freed by the caller. If |buildid| is non-NULL, then a debug object matching it is acceptable. If |buildid| is NULL or doesn't specify a findable debug object, then we look in various places to find a file with the specified CRC. And if that doesn't work out then we give up. */ static DiImage* find_debug_file( struct _DebugInfo* di, const HChar* objpath, const HChar* buildid, const HChar* debugname, UInt crc, Bool rel_ok ) { const HChar* extrapath = VG_(clo_extra_debuginfo_path); const HChar* serverpath = VG_(clo_debuginfo_server); DiImage* dimg = NULL; /* the img that we found */ HChar* debugpath = NULL; /* where we found it */ if (buildid != NULL) { debugpath = ML_(dinfo_zalloc)("di.fdf.1", VG_(strlen)(buildid) + 33); VG_(sprintf)(debugpath, "/usr/lib/debug/.build-id/%c%c/%s.debug", buildid[0], buildid[1], buildid + 2); dimg = open_debug_file(debugpath, buildid, 0, rel_ok, NULL); if (!dimg) { ML_(dinfo_free)(debugpath); debugpath = NULL; } } if (dimg == NULL && debugname != NULL) { HChar *objdir = ML_(dinfo_strdup)("di.fdf.2", objpath); HChar *objdirptr; if ((objdirptr = VG_(strrchr)(objdir, '/')) != NULL) *objdirptr = '\0'; debugpath = ML_(dinfo_zalloc)( "di.fdf.3", VG_(strlen)(objdir) + VG_(strlen)(debugname) + 64 + (extrapath ? VG_(strlen)(extrapath) : 0) + (serverpath ? VG_(strlen)(serverpath) : 0)); VG_(sprintf)(debugpath, "%s/%s", objdir, debugname); dimg = open_debug_file(debugpath, buildid, crc, rel_ok, NULL); if (dimg != NULL) goto dimg_ok; VG_(sprintf)(debugpath, "%s/.debug/%s", objdir, debugname); dimg = open_debug_file(debugpath, buildid, crc, rel_ok, NULL); if (dimg != NULL) goto dimg_ok; VG_(sprintf)(debugpath, "/usr/lib/debug%s/%s", objdir, debugname); dimg = open_debug_file(debugpath, buildid, crc, rel_ok, NULL); if (dimg != NULL) goto dimg_ok; if (extrapath) { VG_(sprintf)(debugpath, "%s%s/%s", extrapath, objdir, debugname); dimg = open_debug_file(debugpath, buildid, crc, rel_ok, NULL); if (dimg != NULL) goto dimg_ok; } if (serverpath) { /* When looking on the debuginfo server, always just pass the basename. */ const HChar* basename = debugname; if (VG_(strstr)(basename, "/") != NULL) { basename = VG_(strrchr)(basename, '/') + 1; } VG_(sprintf)(debugpath, "%s on %s", basename, serverpath); dimg = open_debug_file(basename, buildid, crc, rel_ok, serverpath); if (dimg) goto dimg_ok; } dimg_ok: ML_(dinfo_free)(objdir); } if (dimg != NULL) { vg_assert(debugpath); TRACE_SYMTAB("\n"); TRACE_SYMTAB("------ Found a debuginfo file: %s\n", debugpath); /* Only set once, we might be called again for opening the altfile. */ if (di->fsm.dbgname == NULL) di->fsm.dbgname = ML_(dinfo_strdup)("di.fdf.4", debugpath); } if (debugpath) ML_(dinfo_free)(debugpath); return dimg; } /* Try to find a separate debug file for a given object file, in a hacky and dangerous way: check only the --extra-debuginfo-path and the --debuginfo-server. And don't do a consistency check. */ static DiImage* find_debug_file_ad_hoc( const DebugInfo* di, const HChar* objpath ) { const HChar* extrapath = VG_(clo_extra_debuginfo_path); const HChar* serverpath = VG_(clo_debuginfo_server); DiImage* dimg = NULL; /* the img that we found */ HChar* debugpath = NULL; /* where we found it */ HChar *objdir = ML_(dinfo_strdup)("di.fdfah.1", objpath); HChar *objdirptr; if ((objdirptr = VG_(strrchr)(objdir, '/')) != NULL) *objdirptr = '\0'; debugpath = ML_(dinfo_zalloc)( "di.fdfah.3", VG_(strlen)(objdir) + 64 + (extrapath ? VG_(strlen)(extrapath) : 0) + (serverpath ? VG_(strlen)(serverpath) : 0)); if (extrapath) { VG_(sprintf)(debugpath, "%s/%s", extrapath, objpath); dimg = ML_(img_from_local_file)(debugpath); if (dimg != NULL) { if (VG_(clo_verbosity) > 1) { VG_(message)(Vg_DebugMsg, " Using (POSSIBLY MISMATCHED) %s\n", debugpath); } goto dimg_ok; } } if (serverpath) { /* When looking on the debuginfo server, always just pass the basename. */ const HChar* basename = objpath; if (VG_(strstr)(basename, "/") != NULL) { basename = VG_(strrchr)(basename, '/') + 1; } VG_(sprintf)(debugpath, "%s on %s", basename, serverpath); dimg = ML_(img_from_di_server)(basename, serverpath); if (dimg != NULL) { if (VG_(clo_verbosity) > 1) { VG_(message)(Vg_DebugMsg, " Using (POSSIBLY MISMATCHED) %s\n", debugpath); } goto dimg_ok; } } dimg_ok: ML_(dinfo_free)(objdir); if (dimg != NULL) { vg_assert(debugpath); TRACE_SYMTAB("\n"); TRACE_SYMTAB("------ Found an ad_hoc debuginfo file: %s\n", debugpath); } if (debugpath) ML_(dinfo_free)(debugpath); return dimg; } static DiOffT INDEX_BIS ( DiOffT base, UWord idx, UWord scale ) { // This is a bit stupid. Really, idx and scale ought to be // 64-bit quantities, always. return base + (DiOffT)idx * (DiOffT)scale; } /* Find the file offset corresponding to SVMA by using the program headers. This is taken from binutils-2.17/binutils/readelf.c offset_from_vma(). */ static Word file_offset_from_svma ( /*OUT*/Bool* ok, Addr svma, DiImage* img, DiOffT phdr_ioff, Word phdr_nent, Word phdr_ent_szB ) { Word i; for (i = 0; i < phdr_nent; i++) { ElfXX_Phdr seg; ML_(img_get)(&seg, img, INDEX_BIS(phdr_ioff, i, phdr_ent_szB), sizeof(seg)); if (seg.p_type != PT_LOAD) continue; if (svma >= (seg.p_vaddr & -seg.p_align) && svma + 1 <= seg.p_vaddr + seg.p_filesz) { *ok = True; return svma - seg.p_vaddr + seg.p_offset; } } *ok = False; return 0; } /* The central function for reading ELF debug info. For the object/exe specified by the DebugInfo, find ELF sections, then read the symbols, line number info, file name info, CFA (stack-unwind info) and anything else we want, into the tables within the supplied DebugInfo. */ Bool ML_(read_elf_debug_info) ( struct _DebugInfo* di ) { /* This function is long and complex. That, and the presence of nested scopes, means it's not always easy to see which parts are in loops/conditionals and which aren't. To make it easier to follow, points executed exactly once -- that is, those which are the top level of the function -- are marked TOPLEVEL. */ /* Consistent terminology for local variable names, without which it's almost unfollowably complex: In which file? in the main ELF file *_m* in the debuginfo file *_d* in the alt debuginfo file *_a* What kind of thing? _{m,d,a}img a DiImage* _{m,d,a}ioff an offset in the image (DiOffT) _{m,d,a}nent "number of entries" _{m,d,a}ent_szB "size in bytes of an entry" ehdr_{m,d,a} ELF header phdr Program header shdr Section header a_X a temporary X _escn an DiSlice (elf section info) variable szB size in bytes */ /* TOPLEVEL */ Bool res, ok; Word i, j; Bool dynbss_present = False; Bool sdynbss_present = False; /* Image for the main ELF file we're working with. */ DiImage* mimg = NULL; /* Ditto for any ELF debuginfo file that we might happen to load. */ DiImage* dimg = NULL; /* Ditto for alternate ELF debuginfo file that we might happen to load. */ DiImage* aimg = NULL; /* ELF header offset for the main file. Should be zero since the ELF header is at start of file. */ DiOffT ehdr_mioff = 0; /* Program header table image addr, # entries, entry size */ DiOffT phdr_mioff = 0; UWord phdr_mnent = 0; UWord phdr_ment_szB = 0; /* Section header image addr, # entries, entry size. Also the associated string table. */ DiOffT shdr_mioff = 0; UWord shdr_mnent = 0; UWord shdr_ment_szB = 0; DiOffT shdr_strtab_mioff = 0; /* SVMAs covered by rx and rw segments and corresponding biases. Normally each object would provide just one rx and one rw area, but various ELF mangling tools create objects with multiple such entries, hence the generality. */ typedef struct { Addr svma_base; Addr svma_limit; PtrdiffT bias; Bool exec; } RangeAndBias; XArray* /* of RangeAndBias */ svma_ranges = NULL; vg_assert(di); vg_assert(di->fsm.have_rx_map == True); vg_assert(di->fsm.have_rw_map == True); vg_assert(di->have_dinfo == False); vg_assert(di->fsm.filename); vg_assert(!di->symtab); vg_assert(!di->loctab); vg_assert(!di->inltab); vg_assert(!di->cfsi_base); vg_assert(!di->cfsi_m_ix); vg_assert(!di->cfsi_rd); vg_assert(!di->cfsi_exprs); vg_assert(!di->strpool); vg_assert(!di->fndnpool); vg_assert(!di->soname); { Bool has_nonempty_rx = False; Bool has_nonempty_rw = False; for (i = 0; i < VG_(sizeXA)(di->fsm.maps); i++) { DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, i); if (!map->rx && !map->rw) continue; if (map->rx && map->size > 0) has_nonempty_rx = True; if (map->rw && map->size > 0) has_nonempty_rw = True; /* If this doesn't hold true, it means that m_syswrap/m_aspacemgr managed to do a mapping where the start isn't page aligned. Which sounds pretty bogus to me. */ vg_assert(VG_IS_PAGE_ALIGNED(map->avma)); } vg_assert(has_nonempty_rx); vg_assert(has_nonempty_rw); } /* ---------------------------------------------------------- At this point, there is very little information in the DebugInfo. We only know that something that looks like an ELF file has been mapped rx-ishly and rw-ishly as recorded in the di->fsm.maps array items. First we examine the file's ELF Program Header, and, by comparing that against the di->fsm.maps info, try to figure out the AVMAs for the sections we care about, that should have been mapped: text, data, sdata, bss, got, plt, and toc. ---------------------------------------------------------- */ res = False; if (VG_(clo_verbosity) > 1 || VG_(clo_trace_redir)) VG_(message)(Vg_DebugMsg, "Reading syms from %s\n", di->fsm.filename ); /* Connect to the primary object image, so that we can read symbols and line number info out of it. It will be disconnected immediately thereafter; it is only connected transiently. */ mimg = ML_(img_from_local_file)(di->fsm.filename); if (mimg == NULL) { VG_(message)(Vg_UserMsg, "warning: connection to image %s failed\n", di->fsm.filename ); VG_(message)(Vg_UserMsg, " no symbols or debug info loaded\n" ); return False; } /* Ok, the object image is available. Now verify that it is a valid ELF .so or executable image. */ ok = is_elf_object_file_by_DiImage(mimg, False); if (!ok) { ML_(symerr)(di, True, "Invalid ELF Header"); goto out; } /* Find where the program and section header tables are, and give up if either is missing or outside the image (bogus). */ ElfXX_Ehdr ehdr_m; vg_assert(ehdr_mioff == 0); // ensured by its initialisation ok = ML_(img_valid)(mimg, ehdr_mioff, sizeof(ehdr_m)); vg_assert(ok); // ML_(is_elf_object_file) should ensure this ML_(img_get)(&ehdr_m, mimg, ehdr_mioff, sizeof(ehdr_m)); phdr_mioff = ehdr_mioff + ehdr_m.e_phoff; phdr_mnent = ehdr_m.e_phnum; phdr_ment_szB = ehdr_m.e_phentsize; shdr_mioff = ehdr_mioff + ehdr_m.e_shoff; shdr_mnent = ehdr_m.e_shnum; shdr_ment_szB = ehdr_m.e_shentsize; TRACE_SYMTAB("------ Basic facts about the object ------\n"); TRACE_SYMTAB("object: n_oimage %llu\n", (ULong)ML_(img_size)(mimg)); TRACE_SYMTAB("phdr: ioff %llu nent %ld ent_szB %ld\n", phdr_mioff, phdr_mnent, phdr_ment_szB); TRACE_SYMTAB("shdr: ioff %llu nent %ld ent_szB %ld\n", shdr_mioff, shdr_mnent, shdr_ment_szB); for (i = 0; i < VG_(sizeXA)(di->fsm.maps); i++) { const DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, i); if (map->rx) TRACE_SYMTAB("rx_map: avma %#lx size %lu foff %lu\n", map->avma, map->size, map->foff); } for (i = 0; i < VG_(sizeXA)(di->fsm.maps); i++) { const DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, i); if (map->rw) TRACE_SYMTAB("rw_map: avma %#lx size %lu foff %lu\n", map->avma, map->size, map->foff); } if (phdr_mnent == 0 || !ML_(img_valid)(mimg, phdr_mioff, phdr_mnent * phdr_ment_szB)) { ML_(symerr)(di, True, "Missing or invalid ELF Program Header Table"); goto out; } if (shdr_mnent == 0 || !ML_(img_valid)(mimg, shdr_mioff, shdr_mnent * shdr_ment_szB)) { ML_(symerr)(di, True, "Missing or invalid ELF Section Header Table"); goto out; } /* Also find the section header's string table, and validate. */ /* checked previously by is_elf_object_file: */ vg_assert(ehdr_m.e_shstrndx != SHN_UNDEF); // shdr_mioff is the offset of the section header table // and we need the ehdr_m.e_shstrndx'th entry { ElfXX_Shdr a_shdr; ML_(img_get)(&a_shdr, mimg, INDEX_BIS(shdr_mioff, ehdr_m.e_shstrndx, shdr_ment_szB), sizeof(a_shdr)); shdr_strtab_mioff = ehdr_mioff /* isn't this always zero? */ + a_shdr.sh_offset; if (!ML_(img_valid)(mimg, shdr_strtab_mioff, 1/*bogus, but we don't know the real size*/ )) { ML_(symerr)(di, True, "Invalid ELF Section Header String Table"); goto out; } } TRACE_SYMTAB("shdr: string table at %llu\n", shdr_strtab_mioff); svma_ranges = VG_(newXA)(ML_(dinfo_zalloc), "di.relfdi.1", ML_(dinfo_free), sizeof(RangeAndBias)); /* TOPLEVEL */ /* Look through the program header table, and: - copy information from suitable PT_LOAD entries into svma_ranges - find (or fake up) the .soname for this object. */ TRACE_SYMTAB("\n"); TRACE_SYMTAB("------ Examining the program headers ------\n"); vg_assert(di->soname == NULL); { /* TOPLEVEL */ ElfXX_Addr prev_svma = 0; for (i = 0; i < phdr_mnent; i++) { ElfXX_Phdr a_phdr; ML_(img_get)(&a_phdr, mimg, INDEX_BIS(phdr_mioff, i, phdr_ment_szB), sizeof(a_phdr)); /* Make sure the PT_LOADable entries are in order and non-overlapping. This in turn means the address ranges slurped into svma_ranges are in order and non-overlapping. */ if (a_phdr.p_type == PT_LOAD) { TRACE_SYMTAB("PT_LOAD[%ld]: p_vaddr %#lx (prev %#lx)\n", i, (UWord)a_phdr.p_vaddr, (UWord)prev_svma); TRACE_SYMTAB("PT_LOAD[%ld]: p_offset %lu, p_filesz %lu," " perms %c%c%c\n", i, (UWord)a_phdr.p_offset, (UWord)a_phdr.p_filesz, a_phdr.p_flags & PF_R ? 'r' : '-', a_phdr.p_flags & PF_W ? 'w' : '-', a_phdr.p_flags & PF_X ? 'x' : '-'); if (a_phdr.p_vaddr < prev_svma) { ML_(symerr)(di, True, "ELF Program Headers are not in ascending order"); goto out; } prev_svma = a_phdr.p_vaddr; if (a_phdr.p_memsz > 0) { Bool loaded = False; for (j = 0; j < VG_(sizeXA)(di->fsm.maps); j++) { const DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, j); if ( (map->rx || map->rw) && map->size > 0 /* stay sane */ && a_phdr.p_offset >= map->foff && a_phdr.p_offset < map->foff + map->size && a_phdr.p_offset + a_phdr.p_filesz <= map->foff + map->size) { RangeAndBias item; item.svma_base = a_phdr.p_vaddr; item.svma_limit = a_phdr.p_vaddr + a_phdr.p_memsz; item.bias = map->avma - map->foff + a_phdr.p_offset - a_phdr.p_vaddr; if (map->rw && (a_phdr.p_flags & (PF_R | PF_W)) == (PF_R | PF_W)) { item.exec = False; VG_(addToXA)(svma_ranges, &item); TRACE_SYMTAB( "PT_LOAD[%ld]: acquired as rw, bias 0x%lx\n", i, item.bias); loaded = True; } if (map->rx && (a_phdr.p_flags & (PF_R | PF_X)) == (PF_R | PF_X)) { item.exec = True; VG_(addToXA)(svma_ranges, &item); TRACE_SYMTAB( "PT_LOAD[%ld]: acquired as rx, bias 0x%lx\n", i, item.bias); loaded = True; } } } if (!loaded) { ML_(symerr)(di, False, "ELF section outside all mapped regions"); /* This problem might be solved by further memory mappings. Avoid the vg_assert(!di->soname) at the beginning of this function if DYNAMIC section has been already processed. */ if (di->soname) { ML_(dinfo_free)(di->soname); di->soname = NULL; } goto out; } } } /* Try to get the soname. If there isn't one, use "NONE". The seginfo needs to have some kind of soname in order to facilitate writing redirect functions, since all redirect specifications require a soname (pattern). */ if (a_phdr.p_type == PT_DYNAMIC && di->soname == NULL) { Word stroff = -1; DiOffT strtab_mioff = DiOffT_INVALID; for (j = 0; True/*exit check is in the loop*/; j++) { ElfXX_Dyn t_dyn_m; /* dyn_img[j] */ ML_(img_get)(&t_dyn_m, mimg, INDEX_BIS(ehdr_mioff + a_phdr.p_offset, j, sizeof(ElfXX_Dyn)), sizeof(t_dyn_m)); if (t_dyn_m.d_tag == DT_NULL) break; switch (t_dyn_m.d_tag) { case DT_SONAME: { stroff = t_dyn_m.d_un.d_val; break; } case DT_STRTAB: { Bool ok2 = False; Word offset = file_offset_from_svma( &ok2, t_dyn_m.d_un.d_ptr, mimg, phdr_mioff, phdr_mnent, phdr_ment_szB ); if (ok2 && strtab_mioff == DiOffT_INVALID) { // Check for obviously bogus offsets. if (!ML_(img_valid)(mimg, offset, 1)) { ML_(symerr)(di, True, "Invalid DT_STRTAB offset"); goto out; } strtab_mioff = ehdr_mioff + offset; vg_assert(ehdr_mioff == 0); // should always be } break; } default: break; } } if (stroff != -1 && strtab_mioff != DiOffT_INVALID) { di->soname = ML_(img_strdup)(mimg, "di.redi.1", strtab_mioff + stroff); TRACE_SYMTAB("Found soname = %s\n", di->soname); } } } /* for (i = 0; i < phdr_Mnent; i++) ... */ /* TOPLEVEL */ } /* examine the program headers (local scope) */ /* TOPLEVEL */ /* If, after looking at all the program headers, we still didn't find a soname, add a fake one. */ if (di->soname == NULL) { TRACE_SYMTAB("No soname found; using (fake) \"NONE\"\n"); di->soname = ML_(dinfo_strdup)("di.redi.2", "NONE"); } vg_assert(VG_(sizeXA)(svma_ranges) != 0); /* Now read the section table. */ TRACE_SYMTAB("\n"); TRACE_SYMTAB("------ Examining the section headers ------\n"); for (i = 0; i < VG_(sizeXA)(di->fsm.maps); i++) { const DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, i); if (map->rx) TRACE_SYMTAB("rx: at %#lx are mapped foffsets %ld .. %ld\n", map->avma, map->foff, map->foff + map->size - 1 ); } TRACE_SYMTAB("rx: contains these svma regions:\n"); for (i = 0; i < VG_(sizeXA)(svma_ranges); i++) { const RangeAndBias* reg = VG_(indexXA)(svma_ranges, i); if (reg->exec) TRACE_SYMTAB(" svmas %#lx .. %#lx with bias %#lx\n", reg->svma_base, reg->svma_limit - 1, reg->bias ); } for (i = 0; i < VG_(sizeXA)(di->fsm.maps); i++) { const DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, i); if (map->rw) TRACE_SYMTAB("rw: at %#lx are mapped foffsets %ld .. %ld\n", map->avma, map->foff, map->foff + map->size - 1 ); } TRACE_SYMTAB("rw: contains these svma regions:\n"); for (i = 0; i < VG_(sizeXA)(svma_ranges); i++) { const RangeAndBias* reg = VG_(indexXA)(svma_ranges, i); if (!reg->exec) TRACE_SYMTAB(" svmas %#lx .. %#lx with bias %#lx\n", reg->svma_base, reg->svma_limit - 1, reg->bias ); } /* TOPLEVEL */ /* Iterate over section headers */ for (i = 0; i < shdr_mnent; i++) { ElfXX_Shdr a_shdr; ML_(img_get)(&a_shdr, mimg, INDEX_BIS(shdr_mioff, i, shdr_ment_szB), sizeof(a_shdr)); DiOffT name_mioff = shdr_strtab_mioff + a_shdr.sh_name; HChar* name = ML_(img_strdup)(mimg, "di.redi_name.1", name_mioff); Addr svma = a_shdr.sh_addr; OffT foff = a_shdr.sh_offset; UWord size = a_shdr.sh_size; /* Do not change this to be signed. */ UInt alyn = a_shdr.sh_addralign; Bool bits = !(a_shdr.sh_type == SHT_NOBITS); /* Look through our collection of info obtained from the PT_LOAD headers, and make 'inrx' and 'inrw' point to the first entry in each that intersects 'avma'. If in each case none is found, leave the relevant pointer at NULL. */ RangeAndBias* inrx = NULL; RangeAndBias* inrw = NULL; for (j = 0; j < VG_(sizeXA)(svma_ranges); j++) { RangeAndBias* rng = VG_(indexXA)(svma_ranges, j); if (svma >= rng->svma_base && svma < rng->svma_limit) { if (!inrx && rng->exec) { inrx = rng; } else if (!inrw && !rng->exec) { inrw = rng; } if (inrx && inrw) break; } } TRACE_SYMTAB(" [sec %2ld] %s %s al%2u foff %6ld .. %6ld " " svma %p name \"%s\"\n", i, inrx ? "rx" : " ", inrw ? "rw" : " ", alyn, foff, foff+size-1, (void*)svma, name); /* Check for sane-sized segments. SHT_NOBITS sections have zero size in the file. */ if ((foff >= ML_(img_size)(mimg)) || (foff + (bits ? size : 0) > ML_(img_size)(mimg))) { ML_(symerr)(di, True, "ELF Section extends beyond image end"); goto out; } /* Check for a sane alignment value. */ if (alyn > 0 && -1 == VG_(log2)(alyn)) { ML_(symerr)(di, True, "ELF Section contains invalid " ".sh_addralign value"); goto out; } /* Ignore zero sized sections. */ if (size == 0) { TRACE_SYMTAB("zero sized section \"%s\", ignoring\n", name); ML_(dinfo_free)(name); continue; } # define BAD(_secname) \ do { ML_(symerr)(di, True, \ "Can't make sense of " _secname \ " section mapping"); \ /* make sure we don't assert if we find */ \ /* ourselves back in this routine later, */ \ /* with the same di */ \ di->soname = NULL; \ goto out; \ } while (0) /* Find avma-s for: .text .data .sdata .rodata .bss .sbss .plt .got .opd and .eh_frame */ /* Accept .text where mapped as rx (code), even if zero-sized */ if (0 == VG_(strcmp)(name, ".text")) { if (inrx && !di->text_present) { di->text_present = True; di->text_svma = svma; di->text_avma = svma + inrx->bias; di->text_size = size; di->text_bias = inrx->bias; di->text_debug_svma = svma; di->text_debug_bias = inrx->bias; TRACE_SYMTAB("acquiring .text svma = %#lx .. %#lx\n", di->text_svma, di->text_svma + di->text_size - 1); TRACE_SYMTAB("acquiring .text avma = %#lx .. %#lx\n", di->text_avma, di->text_avma + di->text_size - 1); TRACE_SYMTAB("acquiring .text bias = %#lx\n", di->text_bias); } else { BAD(".text"); } } /* Accept .data where mapped as rw (data), even if zero-sized */ if (0 == VG_(strcmp)(name, ".data")) { if (inrw && !di->data_present) { di->data_present = True; di->data_svma = svma; di->data_avma = svma + inrw->bias; di->data_size = size; di->data_bias = inrw->bias; di->data_debug_svma = svma; di->data_debug_bias = inrw->bias; TRACE_SYMTAB("acquiring .data svma = %#lx .. %#lx\n", di->data_svma, di->data_svma + di->data_size - 1); TRACE_SYMTAB("acquiring .data avma = %#lx .. %#lx\n", di->data_avma, di->data_avma + di->data_size - 1); TRACE_SYMTAB("acquiring .data bias = %#lx\n", di->data_bias); } else { BAD(".data"); } } /* Accept .sdata where mapped as rw (data) */ if (0 == VG_(strcmp)(name, ".sdata")) { if (inrw && !di->sdata_present) { di->sdata_present = True; di->sdata_svma = svma; di->sdata_avma = svma + inrw->bias; di->sdata_size = size; di->sdata_bias = inrw->bias; di->sdata_debug_svma = svma; di->sdata_debug_bias = inrw->bias; TRACE_SYMTAB("acquiring .sdata svma = %#lx .. %#lx\n", di->sdata_svma, di->sdata_svma + di->sdata_size - 1); TRACE_SYMTAB("acquiring .sdata avma = %#lx .. %#lx\n", di->sdata_avma, di->sdata_avma + di->sdata_size - 1); TRACE_SYMTAB("acquiring .sdata bias = %#lx\n", di->sdata_bias); } else { BAD(".sdata"); } } /* Accept .rodata where mapped as rx (data), even if zero-sized */ if (0 == VG_(strcmp)(name, ".rodata")) { if (inrx && !di->rodata_present) { di->rodata_present = True; di->rodata_svma = svma; di->rodata_avma = svma + inrx->bias; di->rodata_size = size; di->rodata_bias = inrx->bias; di->rodata_debug_svma = svma; di->rodata_debug_bias = inrx->bias; /* NB was 'inrw' prior to r11794 */ TRACE_SYMTAB("acquiring .rodata svma = %#lx .. %#lx\n", di->rodata_svma, di->rodata_svma + di->rodata_size - 1); TRACE_SYMTAB("acquiring .rodata avma = %#lx .. %#lx\n", di->rodata_avma, di->rodata_avma + di->rodata_size - 1); TRACE_SYMTAB("acquiring .rodata bias = %#lx\n", di->rodata_bias); } else { BAD(".rodata"); } } if (0 == VG_(strcmp)(name, ".dynbss")) { if (inrw && !di->bss_present) { dynbss_present = True; di->bss_present = True; di->bss_svma = svma; di->bss_avma = svma + inrw->bias; di->bss_size = size; di->bss_bias = inrw->bias; di->bss_debug_svma = svma; di->bss_debug_bias = inrw->bias; TRACE_SYMTAB("acquiring .dynbss svma = %#lx .. %#lx\n", di->bss_svma, di->bss_svma + di->bss_size - 1); TRACE_SYMTAB("acquiring .dynbss avma = %#lx .. %#lx\n", di->bss_avma, di->bss_avma + di->bss_size - 1); TRACE_SYMTAB("acquiring .dynbss bias = %#lx\n", di->bss_bias); } } /* Accept .bss where mapped as rw (data), even if zero-sized */ if (0 == VG_(strcmp)(name, ".bss")) { if (inrw && dynbss_present) { vg_assert(di->bss_present); dynbss_present = False; vg_assert(di->bss_svma + di->bss_size == svma); di->bss_size += size; TRACE_SYMTAB("acquiring .bss svma = %#lx .. %#lx\n", svma, svma + size - 1); TRACE_SYMTAB("acquiring .bss avma = %#lx .. %#lx\n", svma + inrw->bias, svma + inrw->bias + size - 1); TRACE_SYMTAB("acquiring .bss bias = %#lx\n", di->bss_bias); } else if (inrw && !di->bss_present) { di->bss_present = True; di->bss_svma = svma; di->bss_avma = svma + inrw->bias; di->bss_size = size; di->bss_bias = inrw->bias; di->bss_debug_svma = svma; di->bss_debug_bias = inrw->bias; TRACE_SYMTAB("acquiring .bss svma = %#lx .. %#lx\n", di->bss_svma, di->bss_svma + di->bss_size - 1); TRACE_SYMTAB("acquiring .bss avma = %#lx .. %#lx\n", di->bss_avma, di->bss_avma + di->bss_size - 1); TRACE_SYMTAB("acquiring .bss bias = %#lx\n", di->bss_bias); } else /* Now one from the wtf?! department ... */ if (inrx && (!inrw) && !di->bss_present) { /* File contains a .bss, but it got mapped as rx only. This is very strange. For now, just pretend we didn't see it :-) */ di->bss_present = False; di->bss_svma = 0; di->bss_avma = 0; di->bss_size = 0; di->bss_bias = 0; di->bss_debug_svma = 0; di->bss_debug_bias = 0; if (!VG_(clo_xml)) { VG_(message)(Vg_UserMsg, "Warning: the following file's .bss is " "mapped r-x only - ignoring .bss syms\n"); VG_(message)(Vg_UserMsg, " %s\n", di->fsm.filename ? di->fsm.filename : "(null?!)" ); } } else if ((!inrw) && (!inrx) && !di->bss_present) { /* File contains a .bss, but it didn't get mapped. Ignore. */ di->bss_present = False; di->bss_svma = 0; di->bss_avma = 0; di->bss_size = 0; di->bss_bias = 0; } else { BAD(".bss"); } } if (0 == VG_(strcmp)(name, ".sdynbss")) { if (inrw && !di->sbss_present) { sdynbss_present = True; di->sbss_present = True; di->sbss_svma = svma; di->sbss_avma = svma + inrw->bias; di->sbss_size = size; di->sbss_bias = inrw->bias; di->sbss_debug_svma = svma; di->sbss_debug_bias = inrw->bias; TRACE_SYMTAB("acquiring .sdynbss svma = %#lx .. %#lx\n", di->sbss_svma, di->sbss_svma + di->sbss_size - 1); TRACE_SYMTAB("acquiring .sdynbss avma = %#lx .. %#lx\n", di->sbss_avma, di->sbss_avma + di->sbss_size - 1); TRACE_SYMTAB("acquiring .sdynbss bias = %#lx\n", di->sbss_bias); } } /* Accept .sbss where mapped as rw (data) */ if (0 == VG_(strcmp)(name, ".sbss")) { if (inrw && sdynbss_present) { vg_assert(di->sbss_present); sdynbss_present = False; vg_assert(di->sbss_svma + di->sbss_size == svma); di->sbss_size += size; TRACE_SYMTAB("acquiring .sbss svma = %#lx .. %#lx\n", svma, svma + size - 1); TRACE_SYMTAB("acquiring .sbss avma = %#lx .. %#lx\n", svma + inrw->bias, svma + inrw->bias + size - 1); TRACE_SYMTAB("acquiring .sbss bias = %#lx\n", di->sbss_bias); } else if (inrw && !di->sbss_present) { di->sbss_present = True; di->sbss_svma = svma; di->sbss_avma = svma + inrw->bias; di->sbss_size = size; di->sbss_bias = inrw->bias; di->sbss_debug_svma = svma; di->sbss_debug_bias = inrw->bias; TRACE_SYMTAB("acquiring .sbss svma = %#lx .. %#lx\n", di->sbss_svma, di->sbss_svma + di->sbss_size - 1); TRACE_SYMTAB("acquiring .sbss avma = %#lx .. %#lx\n", di->sbss_avma, di->sbss_avma + di->sbss_size - 1); TRACE_SYMTAB("acquiring .sbss bias = %#lx\n", di->sbss_bias); } else { BAD(".sbss"); } } /* Accept .got where mapped as rw (data) */ if (0 == VG_(strcmp)(name, ".got")) { if (inrw && !di->got_present) { di->got_present = True; di->got_avma = svma + inrw->bias; di->got_size = size; TRACE_SYMTAB("acquiring .got avma = %#lx\n", di->got_avma); } else { BAD(".got"); } } /* Accept .got.plt where mapped as rw (data) */ if (0 == VG_(strcmp)(name, ".got.plt")) { if (inrw && !di->gotplt_present) { di->gotplt_present = True; di->gotplt_avma = svma + inrw->bias; di->gotplt_size = size; TRACE_SYMTAB("acquiring .got.plt avma = %#lx\n", di->gotplt_avma); } else if (size != 0) { BAD(".got.plt"); } } /* PLT is different on different platforms, it seems. */ # if defined(VGP_x86_linux) || defined(VGP_amd64_linux) \ || defined(VGP_arm_linux) || defined (VGP_s390x_linux) \ || defined(VGP_mips32_linux) || defined(VGP_mips64_linux) \ || defined(VGP_arm64_linux) || defined(VGP_tilegx_linux) /* Accept .plt where mapped as rx (code) */ if (0 == VG_(strcmp)(name, ".plt")) { if (inrx && !di->plt_present) { di->plt_present = True; di->plt_avma = svma + inrx->bias; di->plt_size = size; TRACE_SYMTAB("acquiring .plt avma = %#lx\n", di->plt_avma); } else { BAD(".plt"); } } # elif defined(VGP_ppc32_linux) /* Accept .plt where mapped as rw (data) */ if (0 == VG_(strcmp)(name, ".plt")) { if (inrw && !di->plt_present) { di->plt_present = True; di->plt_avma = svma + inrw->bias; di->plt_size = size; TRACE_SYMTAB("acquiring .plt avma = %#lx\n", di->plt_avma); } else { BAD(".plt"); } } # elif defined(VGP_ppc64be_linux) || defined(VGP_ppc64le_linux) /* Accept .plt where mapped as rw (data), or unmapped */ if (0 == VG_(strcmp)(name, ".plt")) { if (inrw && !di->plt_present) { di->plt_present = True; di->plt_avma = svma + inrw->bias; di->plt_size = size; TRACE_SYMTAB("acquiring .plt avma = %#lx\n", di->plt_avma); } else if ((!inrw) && (!inrx) && size > 0 && !di->plt_present) { /* File contains a .plt, but it didn't get mapped. Presumably it is not required on this platform. At least don't reject the situation as invalid. */ di->plt_present = True; di->plt_avma = 0; di->plt_size = 0; } else { BAD(".plt"); } } # else # error "Unsupported platform" # endif /* Accept .opd where mapped as rw (data) */ if (0 == VG_(strcmp)(name, ".opd")) { if (inrw && !di->opd_present) { di->opd_present = True; di->opd_avma = svma + inrw->bias; di->opd_size = size; TRACE_SYMTAB("acquiring .opd avma = %#lx\n", di->opd_avma); } else { BAD(".opd"); } } /* Accept .eh_frame where mapped as rx (code). This seems to be the common case. However, if that doesn't pan out, try for rw (data) instead. We can handle up to N_EHFRAME_SECTS per ELF object. */ if (0 == VG_(strcmp)(name, ".eh_frame")) { if (inrx && di->n_ehframe < N_EHFRAME_SECTS) { di->ehframe_avma[di->n_ehframe] = svma + inrx->bias; di->ehframe_size[di->n_ehframe] = size; TRACE_SYMTAB("acquiring .eh_frame avma = %#lx\n", di->ehframe_avma[di->n_ehframe]); di->n_ehframe++; } else if (inrw && di->n_ehframe < N_EHFRAME_SECTS) { di->ehframe_avma[di->n_ehframe] = svma + inrw->bias; di->ehframe_size[di->n_ehframe] = size; TRACE_SYMTAB("acquiring .eh_frame avma = %#lx\n", di->ehframe_avma[di->n_ehframe]); di->n_ehframe++; } else { BAD(".eh_frame"); } } /* Accept .ARM.exidx where mapped as rx (code). */ /* FIXME: make sure the entire section is mapped in, not just the first address. */ if (0 == VG_(strcmp)(name, ".ARM.exidx")) { if (inrx && !di->exidx_present) { di->exidx_present = True; di->exidx_svma = svma; di->exidx_avma = svma + inrx->bias; di->exidx_size = size; di->exidx_bias = inrx->bias; TRACE_SYMTAB("acquiring .exidx svma = %#lx .. %#lx\n", di->exidx_svma, di->exidx_svma + di->exidx_size - 1); TRACE_SYMTAB("acquiring .exidx avma = %#lx .. %#lx\n", di->exidx_avma, di->exidx_avma + di->exidx_size - 1); TRACE_SYMTAB("acquiring .exidx bias = %#lx\n", di->exidx_bias); } else { BAD(".ARM.exidx"); } } /* Accept .ARM.extab where mapped as rx (code). */ /* FIXME: make sure the entire section is mapped in, not just the first address. */ if (0 == VG_(strcmp)(name, ".ARM.extab")) { if (inrx && !di->extab_present) { di->extab_present = True; di->extab_svma = svma; di->extab_avma = svma + inrx->bias; di->extab_size = size; di->extab_bias = inrx->bias; TRACE_SYMTAB("acquiring .extab svma = %#lx .. %#lx\n", di->extab_svma, di->extab_svma + di->extab_size - 1); TRACE_SYMTAB("acquiring .extab avma = %#lx .. %#lx\n", di->extab_avma, di->extab_avma + di->extab_size - 1); TRACE_SYMTAB("acquiring .extab bias = %#lx\n", di->extab_bias); } else { BAD(".ARM.extab"); } } ML_(dinfo_free)(name); # undef BAD } /* iterate over the section headers */ /* TOPLEVEL */ if (0) VG_(printf)("YYYY text_: avma %#lx size %ld bias %#lx\n", di->text_avma, di->text_size, di->text_bias); if (VG_(clo_verbosity) > 2 || VG_(clo_trace_redir)) VG_(message)(Vg_DebugMsg, " svma %#010lx, avma %#010lx\n", di->text_avma - di->text_bias, di->text_avma ); TRACE_SYMTAB("\n"); TRACE_SYMTAB("------ Finding image addresses " "for debug-info sections ------\n"); /* TOPLEVEL */ /* Find interesting sections, read the symbol table(s), read any debug information. Each section is located either in the main, debug or alt-debug files, but only in one. For each section, |section_escn| records which of |mimg|, |dimg| or |aimg| we found it in, along with the section's image offset and its size. The triples (section_img, section_ioff, section_szB) are consistent, in that they are always either (NULL, DiOffT_INVALID, 0), or refer to the same image, and are all assigned together. */ { /* TOPLEVEL */ DiSlice strtab_escn = DiSlice_INVALID; // .strtab DiSlice symtab_escn = DiSlice_INVALID; // .symtab DiSlice dynstr_escn = DiSlice_INVALID; // .dynstr DiSlice dynsym_escn = DiSlice_INVALID; // .dynsym DiSlice debuglink_escn = DiSlice_INVALID; // .gnu_debuglink DiSlice debugaltlink_escn = DiSlice_INVALID; // .gnu_debugaltlink DiSlice debug_line_escn = DiSlice_INVALID; // .debug_line (dwarf2) DiSlice debug_info_escn = DiSlice_INVALID; // .debug_info (dwarf2) DiSlice debug_types_escn = DiSlice_INVALID; // .debug_types (dwarf4) DiSlice debug_abbv_escn = DiSlice_INVALID; // .debug_abbrev (dwarf2) DiSlice debug_str_escn = DiSlice_INVALID; // .debug_str (dwarf2) DiSlice debug_ranges_escn = DiSlice_INVALID; // .debug_ranges (dwarf2) DiSlice debug_loc_escn = DiSlice_INVALID; // .debug_loc (dwarf2) DiSlice debug_frame_escn = DiSlice_INVALID; // .debug_frame (dwarf2) DiSlice debug_line_alt_escn = DiSlice_INVALID; // .debug_line (alt) DiSlice debug_info_alt_escn = DiSlice_INVALID; // .debug_info (alt) DiSlice debug_abbv_alt_escn = DiSlice_INVALID; // .debug_abbrev (alt) DiSlice debug_str_alt_escn = DiSlice_INVALID; // .debug_str (alt) DiSlice dwarf1d_escn = DiSlice_INVALID; // .debug (dwarf1) DiSlice dwarf1l_escn = DiSlice_INVALID; // .line (dwarf1) DiSlice opd_escn = DiSlice_INVALID; // .opd (dwarf2, // ppc64be-linux) DiSlice ehframe_escn[N_EHFRAME_SECTS]; // .eh_frame (dwarf2) for (i = 0; i < N_EHFRAME_SECTS; i++) ehframe_escn[i] = DiSlice_INVALID; /* Find all interesting sections */ UInt ehframe_mix = 0; /* What FIND does: it finds the section called _SEC_NAME. The size of it is assigned to _SEC_SIZE. The address of the section in the transiently loaded oimage is assigned to _SEC_IMG. If the section is found, _POST_FX is executed after _SEC_NAME and _SEC_SIZE have been assigned to. Even for sections which are marked loadable, the client's ld.so may not have loaded them yet, so there is no guarantee that we can safely prod around in any such area). Because the entire object file is transiently mapped aboard for inspection, it's always safe to inspect that area. */ /* TOPLEVEL */ /* Iterate over section headers (again) */ for (i = 0; i < ehdr_m.e_shnum; i++) { # define FINDX(_sec_name, _sec_escn, _post_fx) \ do { \ ElfXX_Shdr a_shdr; \ ML_(img_get)(&a_shdr, mimg, \ INDEX_BIS(shdr_mioff, i, shdr_ment_szB), \ sizeof(a_shdr)); \ if (0 == ML_(img_strcmp_c)(mimg, shdr_strtab_mioff \ + a_shdr.sh_name, _sec_name)) { \ Bool nobits; \ _sec_escn.img = mimg; \ _sec_escn.ioff = (DiOffT)a_shdr.sh_offset; \ _sec_escn.szB = a_shdr.sh_size; \ nobits = a_shdr.sh_type == SHT_NOBITS; \ vg_assert(_sec_escn.img != NULL); \ vg_assert(_sec_escn.ioff != DiOffT_INVALID); \ TRACE_SYMTAB( "%-18s: ioff %llu .. %llu\n", \ _sec_name, (ULong)_sec_escn.ioff, \ ((ULong)_sec_escn.ioff) + _sec_escn.szB - 1); \ /* SHT_NOBITS sections have zero size in the file. */ \ if ( a_shdr.sh_offset \ + (nobits ? 0 : _sec_escn.szB) > ML_(img_size)(mimg) ) { \ ML_(symerr)(di, True, \ " section beyond image end?!"); \ goto out; \ } \ _post_fx; \ } \ } while (0); /* Version with no post-effects */ # define FIND(_sec_name, _sec_escn) \ FINDX(_sec_name, _sec_escn, /**/) /* NAME ElfSec */ FIND(".dynsym", dynsym_escn) FIND(".dynstr", dynstr_escn) FIND(".symtab", symtab_escn) FIND(".strtab", strtab_escn) FIND(".gnu_debuglink", debuglink_escn) FIND(".gnu_debugaltlink", debugaltlink_escn) FIND(".debug_line", debug_line_escn) FIND(".debug_info", debug_info_escn) FIND(".debug_types", debug_types_escn) FIND(".debug_abbrev", debug_abbv_escn) FIND(".debug_str", debug_str_escn) FIND(".debug_ranges", debug_ranges_escn) FIND(".debug_loc", debug_loc_escn) FIND(".debug_frame", debug_frame_escn) FIND(".debug", dwarf1d_escn) FIND(".line", dwarf1l_escn) FIND(".opd", opd_escn) FINDX(".eh_frame", ehframe_escn[ehframe_mix], do { ehframe_mix++; vg_assert(ehframe_mix <= N_EHFRAME_SECTS); } while (0) ) /* Comment_on_EH_FRAME_MULTIPLE_INSTANCES: w.r.t. .eh_frame multi-instance kludgery, how are we assured that the order in which we fill in ehframe_escn[] is consistent with the order in which we previously filled in di->ehframe_avma[] and di->ehframe_size[] ? By the fact that in both cases, these arrays were filled in by iterating over the section headers top-to-bottom. So both loops (this one and the previous one) encounter the .eh_frame entries in the same order and so fill in these arrays in a consistent order. */ # undef FINDX # undef FIND } /* Iterate over section headers (again) */ /* TOPLEVEL */ /* Now, see if we can find a debuginfo object, and if so connect |dimg| to it. */ vg_assert(dimg == NULL && aimg == NULL); /* Look for a build-id */ HChar* buildid = find_buildid(mimg, False, False); /* Look for a debug image that matches either the build-id or the debuglink-CRC32 in the main image. If the main image doesn't contain either of those then this won't even bother to try looking. This looks in all known places, including the --extra-debuginfo-path if specified and on the --debuginfo-server if specified. */ if (buildid != NULL || debuglink_escn.img != NULL) { /* Do have a debuglink section? */ if (debuglink_escn.img != NULL) { UInt crc_offset = VG_ROUNDUP(ML_(img_strlen)(debuglink_escn.img, debuglink_escn.ioff)+1, 4); vg_assert(crc_offset + sizeof(UInt) <= debuglink_escn.szB); /* Extract the CRC from the debuglink section */ UInt crc = ML_(img_get_UInt)(debuglink_escn.img, debuglink_escn.ioff + crc_offset); /* See if we can find a matching debug file */ HChar* debuglink_str_m = ML_(img_strdup)(debuglink_escn.img, "di.redi_dlk.1", debuglink_escn.ioff); dimg = find_debug_file( di, di->fsm.filename, buildid, debuglink_str_m, crc, False ); if (debuglink_str_m) ML_(dinfo_free)(debuglink_str_m); } else { /* See if we can find a matching debug file */ dimg = find_debug_file( di, di->fsm.filename, buildid, NULL, 0, False ); } } if (buildid) { ML_(dinfo_free)(buildid); buildid = NULL; /* paranoia */ } /* As a last-ditch measure, try looking for in the --extra-debuginfo-path and/or on the --debuginfo-server, but only in the case where --allow-mismatched-debuginfo=yes. This is dangerous in that (1) it gives no assurance that the debuginfo object matches the main one, and hence (2) we will very likely get an assertion in the code below, if indeed there is a mismatch. Hence it is disabled by default (--allow-mismatched-debuginfo=no). Nevertheless it's sometimes a useful way of getting out of a tight spot. Note that we're ignoring the name in the .gnu_debuglink section here, and just looking for a file of the same name either the extra-path or on the server. */ if (dimg == NULL && VG_(clo_allow_mismatched_debuginfo)) { dimg = find_debug_file_ad_hoc( di, di->fsm.filename ); } /* TOPLEVEL */ /* If we were successful in finding a debug image, pull various SVMA/bias/size and image addresses out of it. */ if (dimg != NULL && is_elf_object_file_by_DiImage(dimg, False)) { /* Pull out and validate program header and section header info */ DiOffT ehdr_dioff = 0; ElfXX_Ehdr ehdr_dimg; ML_(img_get)(&ehdr_dimg, dimg, ehdr_dioff, sizeof(ehdr_dimg)); DiOffT phdr_dioff = ehdr_dimg.e_phoff; UWord phdr_dnent = ehdr_dimg.e_phnum; UWord phdr_dent_szB = ehdr_dimg.e_phentsize; DiOffT shdr_dioff = ehdr_dimg.e_shoff; UWord shdr_dnent = ehdr_dimg.e_shnum; UWord shdr_dent_szB = ehdr_dimg.e_shentsize; DiOffT shdr_strtab_dioff = DiOffT_INVALID; /* SVMAs covered by rx and rw segments and corresponding bias. */ Addr rx_dsvma_limit = 0; PtrdiffT rx_dbias = 0; Addr rw_dsvma_limit = 0; PtrdiffT rw_dbias = 0; Bool need_symtab, need_dwarf2, need_dwarf1; if (phdr_dnent == 0 || !ML_(img_valid)(dimg, phdr_dioff, phdr_dnent * phdr_dent_szB)) { ML_(symerr)(di, True, "Missing or invalid ELF Program Header Table" " (debuginfo file)"); goto out; } if (shdr_dnent == 0 || !ML_(img_valid)(dimg, shdr_dioff, shdr_dnent * shdr_dent_szB)) { ML_(symerr)(di, True, "Missing or invalid ELF Section Header Table" " (debuginfo file)"); goto out; } /* Also find the section header's string table, and validate. */ /* checked previously by is_elf_object_file: */ vg_assert(ehdr_dimg.e_shstrndx != SHN_UNDEF); // shdr_dioff is the offset of the section header table // and we need the ehdr_dimg.e_shstrndx'th entry { ElfXX_Shdr a_shdr; ML_(img_get)(&a_shdr, dimg, INDEX_BIS(shdr_dioff, ehdr_dimg.e_shstrndx, shdr_dent_szB), sizeof(a_shdr)); shdr_strtab_dioff = a_shdr.sh_offset; if (!ML_(img_valid)(dimg, shdr_strtab_dioff, 1/*bogus, but we don't know the real size*/)) { ML_(symerr)(di, True, "Invalid ELF Section Header String Table" " (debuginfo file)"); goto out; } } for (i = 0; i < ehdr_dimg.e_phnum; i++) { ElfXX_Phdr a_phdr; ML_(img_get)(&a_phdr, dimg, INDEX_BIS(ehdr_dimg.e_phoff, i, phdr_dent_szB), sizeof(a_phdr)); if (a_phdr.p_type == PT_LOAD) { for (j = 0; j < VG_(sizeXA)(di->fsm.maps); j++) { const DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, j); if ( a_phdr.p_offset >= map->foff && a_phdr.p_offset < map->foff + map->size && a_phdr.p_offset + a_phdr.p_filesz < map->foff + map->size) { if (map->rx && rx_dsvma_limit == 0) { rx_dsvma_limit = a_phdr.p_vaddr + a_phdr.p_memsz; rx_dbias = map->avma - map->foff + a_phdr.p_offset - a_phdr.p_vaddr; } if (map->rw && rw_dsvma_limit == 0) { rw_dsvma_limit = a_phdr.p_vaddr + a_phdr.p_memsz; rw_dbias = map->avma - map->foff + a_phdr.p_offset - a_phdr.p_vaddr; } break; } } } } need_symtab = (symtab_escn.img == NULL); need_dwarf2 = (debug_info_escn.img == NULL); need_dwarf1 = (dwarf1d_escn.img == NULL); /* Find all interesting sections in the debug image */ for (i = 0; i < ehdr_dimg.e_shnum; i++) { /* Find debug svma and bias information for sections we found in the main file. */ # define FIND(_sec, _seg) \ do { \ ElfXX_Shdr a_shdr; \ ML_(img_get)(&a_shdr, dimg, \ INDEX_BIS(shdr_dioff, i, shdr_dent_szB), \ sizeof(a_shdr)); \ if (di->_sec##_present \ && 0 == ML_(img_strcmp_c)(dimg, shdr_strtab_dioff \ + a_shdr.sh_name, "." #_sec)) { \ vg_assert(di->_sec##_size == a_shdr.sh_size); \ /* JRS 2013-Jun-01: the following assert doesn't contain */ \ /* any ==s, which seems to me to be suspicious. */ \ vg_assert(di->_sec##_avma + a_shdr.sh_addr + _seg##_dbias); \ /* Assume we have a correct value for the main */ \ /* object's bias. Use that to derive the debuginfo */ \ /* object's bias, by adding the difference in SVMAs */ \ /* for the corresponding sections in the two files. */ \ /* That should take care of all prelinking effects. */ \ di->_sec##_debug_svma = a_shdr.sh_addr; \ di->_sec##_debug_bias \ = di->_sec##_bias + \ di->_sec##_svma - di->_sec##_debug_svma; \ TRACE_SYMTAB("acquiring ." #_sec \ " debug svma = %#lx .. %#lx\n", \ di->_sec##_debug_svma, \ di->_sec##_debug_svma + di->_sec##_size - 1); \ TRACE_SYMTAB("acquiring ." #_sec " debug bias = %#lx\n", \ di->_sec##_debug_bias); \ } \ } while (0); /* SECTION SEGMENT */ FIND(text, rx) FIND(data, rw) FIND(sdata, rw) FIND(rodata, rw) FIND(bss, rw) FIND(sbss, rw) # undef FIND /* Same deal as previous FIND, except only do it for those sections which we didn't find in the main file. */ # define FIND(_condition, _sec_name, _sec_escn) \ do { \ ElfXX_Shdr a_shdr; \ ML_(img_get)(&a_shdr, dimg, \ INDEX_BIS(shdr_dioff, i, shdr_dent_szB), \ sizeof(a_shdr)); \ if (_condition \ && 0 == ML_(img_strcmp_c)(dimg, shdr_strtab_dioff \ + a_shdr.sh_name, _sec_name)) { \ Bool nobits; \ if (_sec_escn.img != NULL) { \ ML_(symerr)(di, True, \ " debuginfo section duplicates a" \ " section in the main ELF file"); \ goto out; \ } \ _sec_escn.img = dimg; \ _sec_escn.ioff = (DiOffT)a_shdr.sh_offset; \ _sec_escn.szB = a_shdr.sh_size; \ nobits = a_shdr.sh_type == SHT_NOBITS; \ vg_assert(_sec_escn.img != NULL); \ vg_assert(_sec_escn.ioff != DiOffT_INVALID); \ TRACE_SYMTAB( "%-18s: dioff %llu .. %llu\n", \ _sec_name, \ (ULong)_sec_escn.ioff, \ ((ULong)_sec_escn.ioff) + _sec_escn.szB - 1); \ /* SHT_NOBITS sections have zero size in the file. */ \ if (a_shdr.sh_offset \ + (nobits ? 0 : _sec_escn.szB) > ML_(img_size)(dimg)) { \ ML_(symerr)(di, True, \ " section beyond image end?!"); \ goto out; \ } \ } \ } while (0); /* NEEDED? NAME ElfSec */ FIND(need_symtab, ".symtab", symtab_escn) FIND(need_symtab, ".strtab", strtab_escn) FIND(need_dwarf2, ".debug_line", debug_line_escn) FIND(need_dwarf2, ".debug_info", debug_info_escn) FIND(need_dwarf2, ".debug_types", debug_types_escn) FIND(need_dwarf2, ".debug_abbrev", debug_abbv_escn) FIND(need_dwarf2, ".debug_str", debug_str_escn) FIND(need_dwarf2, ".debug_ranges", debug_ranges_escn) FIND(need_dwarf2, ".debug_loc", debug_loc_escn) FIND(need_dwarf2, ".debug_frame", debug_frame_escn) FIND(need_dwarf2, ".gnu_debugaltlink", debugaltlink_escn) FIND(need_dwarf1, ".debug", dwarf1d_escn) FIND(need_dwarf1, ".line", dwarf1l_escn) # undef FIND } /* Find all interesting sections */ } /* do we have a debug image? */ /* TOPLEVEL */ /* Look for alternate debug image, and if found, connect |aimg| to it. */ vg_assert(aimg == NULL); if (debugaltlink_escn.img != NULL) { HChar* altfile_str_m = ML_(img_strdup)(debugaltlink_escn.img, "di.fbi.3", debugaltlink_escn.ioff); UInt buildid_offset = ML_(img_strlen)(debugaltlink_escn.img, debugaltlink_escn.ioff)+1; vg_assert(buildid_offset < debugaltlink_escn.szB); HChar *altbuildid = ML_(dinfo_zalloc)("di.fbi.4", (debugaltlink_escn.szB - buildid_offset) * 2 + 1); /* The altfile might be relative to the debug file or main file. */ HChar *dbgname = di->fsm.dbgname ? di->fsm.dbgname : di->fsm.filename; for (j = 0; j < debugaltlink_escn.szB - buildid_offset; j++) VG_(sprintf)( altbuildid + 2 * j, "%02x", (UInt)ML_(img_get_UChar)(debugaltlink_escn.img, debugaltlink_escn.ioff + buildid_offset + j)); /* See if we can find a matching debug file */ aimg = find_debug_file( di, dbgname, altbuildid, altfile_str_m, 0, True ); if (altfile_str_m) ML_(dinfo_free)(altfile_str_m); ML_(dinfo_free)(altbuildid); } /* TOPLEVEL */ /* If we were successful in finding alternate debug image, pull various size and image addresses out of it. */ if (aimg != NULL && is_elf_object_file_by_DiImage(aimg, True)) { /* Pull out and validate program header and section header info */ DiOffT ehdr_aioff = 0; ElfXX_Ehdr ehdr_aimg; ML_(img_get)(&ehdr_aimg, aimg, ehdr_aioff, sizeof(ehdr_aimg)); DiOffT shdr_aioff = ehdr_aimg.e_shoff; UWord shdr_anent = ehdr_aimg.e_shnum; UWord shdr_aent_szB = ehdr_aimg.e_shentsize; DiOffT shdr_strtab_aioff = DiOffT_INVALID; if (shdr_anent == 0 || !ML_(img_valid)(aimg, shdr_aioff, shdr_anent * shdr_aent_szB)) { ML_(symerr)(di, True, "Missing or invalid ELF Section Header Table" " (alternate debuginfo file)"); goto out; } /* Also find the section header's string table, and validate. */ /* checked previously by is_elf_object_file: */ vg_assert(ehdr_aimg.e_shstrndx != SHN_UNDEF); // shdr_aioff is the offset of the section header table // and we need the ehdr_aimg.e_shstrndx'th entry { ElfXX_Shdr a_shdr; ML_(img_get)(&a_shdr, aimg, INDEX_BIS(shdr_aioff, ehdr_aimg.e_shstrndx, shdr_aent_szB), sizeof(a_shdr)); shdr_strtab_aioff = a_shdr.sh_offset; if (!ML_(img_valid)(aimg, shdr_strtab_aioff, 1/*bogus, but we don't know the real size*/)) { ML_(symerr)(di, True, "Invalid ELF Section Header String Table" " (alternate debuginfo file)"); goto out; } } /* Find all interesting sections */ for (i = 0; i < ehdr_aimg.e_shnum; i++) { # define FIND(_sec_name, _sec_escn) \ do { \ ElfXX_Shdr a_shdr; \ ML_(img_get)(&a_shdr, aimg, \ INDEX_BIS(shdr_aioff, i, shdr_aent_szB), \ sizeof(a_shdr)); \ if (0 == ML_(img_strcmp_c)(aimg, shdr_strtab_aioff \ + a_shdr.sh_name, _sec_name)) { \ if (_sec_escn.img != NULL) { \ ML_(symerr)(di, True, \ " alternate debuginfo section duplicates a" \ " section in the main ELF file"); \ goto out; \ } \ _sec_escn.img = aimg; \ _sec_escn.ioff = (DiOffT)a_shdr.sh_offset; \ _sec_escn.szB = a_shdr.sh_size; \ vg_assert(_sec_escn.img != NULL); \ vg_assert(_sec_escn.ioff != DiOffT_INVALID); \ TRACE_SYMTAB( "%-18s: aioff %llu .. %llu\n", \ _sec_name, \ (ULong)_sec_escn.ioff, \ ((ULong)_sec_escn.ioff) + _sec_escn.szB - 1); \ } \ } while (0); /* NAME ElfSec */ FIND(".debug_line", debug_line_alt_escn) FIND(".debug_info", debug_info_alt_escn) FIND(".debug_abbrev", debug_abbv_alt_escn) FIND(".debug_str", debug_str_alt_escn) # undef FIND } /* Find all interesting sections */ } /* do we have a debug image? */ /* TOPLEVEL */ /* Check some sizes */ vg_assert((dynsym_escn.szB % sizeof(ElfXX_Sym)) == 0); vg_assert((symtab_escn.szB % sizeof(ElfXX_Sym)) == 0); /* TOPLEVEL */ /* Read symbols */ { void (*read_elf_symtab)(struct _DebugInfo*, const HChar*, DiSlice*, DiSlice*, DiSlice*, Bool); Bool symtab_in_debug; # if defined(VGP_ppc64be_linux) read_elf_symtab = read_elf_symtab__ppc64be_linux; # else read_elf_symtab = read_elf_symtab__normal; # endif symtab_in_debug = symtab_escn.img == dimg; read_elf_symtab(di, "symbol table", &symtab_escn, &strtab_escn, &opd_escn, symtab_in_debug); read_elf_symtab(di, "dynamic symbol table", &dynsym_escn, &dynstr_escn, &opd_escn, False); } /* TOPLEVEL */ /* Read .eh_frame and .debug_frame (call-frame-info) if any. Do the .eh_frame section(s) first. */ vg_assert(di->n_ehframe >= 0 && di->n_ehframe <= N_EHFRAME_SECTS); for (i = 0; i < di->n_ehframe; i++) { /* see Comment_on_EH_FRAME_MULTIPLE_INSTANCES above for why this next assertion should hold. */ vg_assert(ML_(sli_is_valid)(ehframe_escn[i])); vg_assert(ehframe_escn[i].szB == di->ehframe_size[i]); ML_(read_callframe_info_dwarf3)( di, ehframe_escn[i], di->ehframe_avma[i], True/*is_ehframe*/ ); } if (ML_(sli_is_valid)(debug_frame_escn)) { ML_(read_callframe_info_dwarf3)( di, debug_frame_escn, 0/*assume zero avma*/, False/*!is_ehframe*/ ); } /* TOPLEVEL */ /* jrs 2006-01-01: icc-8.1 has been observed to generate binaries without debug_str sections. Don't preclude debuginfo reading for that reason, but, in read_unitinfo_dwarf2, do check that debugstr is non-NULL before using it. */ if (ML_(sli_is_valid)(debug_info_escn) && ML_(sli_is_valid)(debug_abbv_escn) && ML_(sli_is_valid)(debug_line_escn)) { /* The old reader: line numbers and unwind info only */ ML_(read_debuginfo_dwarf3) ( di, debug_info_escn, debug_types_escn, debug_abbv_escn, debug_line_escn, debug_str_escn, debug_str_alt_escn ); /* The new reader: read the DIEs in .debug_info to acquire information on variable types and locations or inline info. But only if the tool asks for it, or the user requests it on the command line. */ if (VG_(clo_read_var_info) /* the user or tool asked for it */ || VG_(clo_read_inline_info)) { ML_(new_dwarf3_reader)( di, debug_info_escn, debug_types_escn, debug_abbv_escn, debug_line_escn, debug_str_escn, debug_ranges_escn, debug_loc_escn, debug_info_alt_escn, debug_abbv_alt_escn, debug_line_alt_escn, debug_str_alt_escn ); } } /* TOPLEVEL */ // JRS 31 July 2014: dwarf-1 reading is currently broken and // therefore deactivated. //if (dwarf1d_img && dwarf1l_img) { // ML_(read_debuginfo_dwarf1) ( di, dwarf1d_img, dwarf1d_sz, // dwarf1l_img, dwarf1l_sz ); //} # if defined(VGA_arm) /* TOPLEVEL */ /* ARM32 only: read .exidx/.extab if present. Note we are reading these directly out of the mapped in (running) image. Also, read these only if no CFI based unwind info was acquired for this file. An .exidx section is always required, but the .extab section can be optionally omitted, provided that .exidx does not refer to it. If the .exidx is erroneous and does refer to .extab even though .extab is missing, the range checks done by GET_EX_U32 in ExtabEntryExtract in readexidx.c should prevent any invalid memory accesses, and cause the .extab to be rejected as invalid. FIXME: * check with m_aspacemgr that the entire [exidx_avma, +exidx_size) and [extab_avma, +extab_size) areas are readable, since we're reading this stuff out of the running image (not from a file/socket) and we don't want to segfault. * DebugInfo::exidx_bias and use text_bias instead. I think it's always the same. * remove DebugInfo::{extab_bias, exidx_svma, extab_svma} since they are never used. */ if (di->exidx_present && di->cfsi_used == 0 && di->text_present && di->text_size > 0) { Addr text_last_svma = di->text_svma + di->text_size - 1; ML_(read_exidx)( di, (UChar*)di->exidx_avma, di->exidx_size, (UChar*)di->extab_avma, di->extab_size, text_last_svma, di->exidx_bias ); } # endif /* defined(VGA_arm) */ } /* "Find interesting sections, read the symbol table(s), read any debug information" (a local scope) */ /* TOPLEVEL */ res = True; /* If reading Dwarf3 variable type/location info, print a line showing the number of variables read for each object. (Currently disabled -- is a sanity-check mechanism for exp-sgcheck.) */ if (0 && VG_(clo_read_var_info)) { UWord nVars = 0; if (di->varinfo) { for (j = 0; j < VG_(sizeXA)(di->varinfo); j++) { OSet* /* of DiAddrRange */ scope = *(OSet**)VG_(indexXA)(di->varinfo, j); vg_assert(scope); VG_(OSetGen_ResetIter)( scope ); while (True) { DiAddrRange* range = VG_(OSetGen_Next)( scope ); if (!range) break; vg_assert(range->vars); Word w = VG_(sizeXA)(range->vars); vg_assert(w >= 0); if (0) VG_(printf)("range %#lx %#lx %ld\n", range->aMin, range->aMax, w); nVars += (UWord)w; } } } VG_(umsg)("VARINFO: %7lu vars %7ld text_size %s\n", nVars, di->text_size, di->fsm.filename); } /* TOPLEVEL */ out: { /* Last, but not least, detach from the image(s). */ if (mimg) ML_(img_done)(mimg); if (dimg) ML_(img_done)(dimg); if (aimg) ML_(img_done)(aimg); if (svma_ranges) VG_(deleteXA)(svma_ranges); return res; } /* out: */ /* NOTREACHED */ } #endif // defined(VGO_linux) /*--------------------------------------------------------------------*/ /*--- end ---*/ /*--------------------------------------------------------------------*/