From: Mark Wielaard Date: Thu, 26 Aug 2021 17:05:45 +0000 (+0200) Subject: libdw: set address size, offset size and version on fake CUs X-Git-Tag: elfutils-0.186~24 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=52b0d9caf5575a62322c9fbe920b69444dd09162;p=thirdparty%2Felfutils.git libdw: set address size, offset size and version on fake CUs There are three "fake CUs" that are associated with .debug_loc, .debug_loclist and .debug_addr. These fake CUs are used for "fake attributes" to provide values that are stored in these sections instead of in the .debug_info section. These fake CUs didn't have the address size, offset size and DWARF version set. This meant that values that depended on those properties might not be interpreted correctly. One example was the value associated with a DW_OP_addrx (which comes from the .debug_addr section). Add a testcase using varlocs to test that addresses can correctly be retrieved for gcc/clang, DWARF4/5 and 32/64 bits objects. https://sourceware.org/bugzilla/show_bug.cgi?id=28220 Signed-off-by: Mark Wielaard --- diff --git a/libdw/ChangeLog b/libdw/ChangeLog index 768d5c25c..b707bbfe6 100644 --- a/libdw/ChangeLog +++ b/libdw/ChangeLog @@ -1,3 +1,8 @@ +2021-09-08 Mark Wielaard + + * dwarf_begin_elf.c (valid_p): Identify ELF class and use this to set + address_size of the fake CUs. Also set offset_size and DWARF version. + 2021-09-06 Dmitry V. Levin * dwarf_begin_elf.c (valid_p): Remove casts of malloc return values. diff --git a/libdw/dwarf_begin_elf.c b/libdw/dwarf_begin_elf.c index 7bde61b3d..53b44cd43 100644 --- a/libdw/dwarf_begin_elf.c +++ b/libdw/dwarf_begin_elf.c @@ -224,6 +224,23 @@ valid_p (Dwarf *result) result = NULL; } + /* We are setting up some "fake" CUs, which need an address size. + Check the ELF class to come up with something reasonable. */ + int elf_addr_size = 8; + if (result != NULL) + { + GElf_Ehdr ehdr; + if (gelf_getehdr (result->elf, &ehdr) == NULL) + { + Dwarf_Sig8_Hash_free (&result->sig8_hash); + __libdw_seterrno (DWARF_E_INVALID_ELF); + free (result); + result = NULL; + } + else if (ehdr.e_ident[EI_CLASS] == ELFCLASS32) + elf_addr_size = 4; + } + /* For dwarf_location_attr () we need a "fake" CU to indicate where the "fake" attribute data comes from. This is a block inside the .debug_loc or .debug_loclists section. */ @@ -247,8 +264,9 @@ valid_p (Dwarf *result) = (result->sectiondata[IDX_debug_loc]->d_buf + result->sectiondata[IDX_debug_loc]->d_size); result->fake_loc_cu->locs = NULL; - result->fake_loc_cu->address_size = 0; - result->fake_loc_cu->version = 0; + result->fake_loc_cu->address_size = elf_addr_size; + result->fake_loc_cu->offset_size = 4; + result->fake_loc_cu->version = 4; result->fake_loc_cu->split = NULL; } } @@ -274,8 +292,9 @@ valid_p (Dwarf *result) = (result->sectiondata[IDX_debug_loclists]->d_buf + result->sectiondata[IDX_debug_loclists]->d_size); result->fake_loclists_cu->locs = NULL; - result->fake_loclists_cu->address_size = 0; - result->fake_loclists_cu->version = 0; + result->fake_loclists_cu->address_size = elf_addr_size; + result->fake_loclists_cu->offset_size = 4; + result->fake_loclists_cu->version = 5; result->fake_loclists_cu->split = NULL; } } @@ -306,8 +325,9 @@ valid_p (Dwarf *result) = (result->sectiondata[IDX_debug_addr]->d_buf + result->sectiondata[IDX_debug_addr]->d_size); result->fake_addr_cu->locs = NULL; - result->fake_addr_cu->address_size = 0; - result->fake_addr_cu->version = 0; + result->fake_addr_cu->address_size = elf_addr_size; + result->fake_addr_cu->offset_size = 4; + result->fake_addr_cu->version = 5; result->fake_addr_cu->split = NULL; } } diff --git a/tests/ChangeLog b/tests/ChangeLog index caee93d39..1154686a8 100644 --- a/tests/ChangeLog +++ b/tests/ChangeLog @@ -1,3 +1,17 @@ +2021-09-08 Mark Wielaard + + * run-varlocs-vars.sh: New test. + * testfile-vars-clang-dwarf4-32.o.bz2: New test file. + * testfile-vars-clang-dwarf4-64.o.bz2: Likewise. + * testfile-vars-clang-dwarf5-32.o.bz2: Likewise. + * testfile-vars-clang-dwarf5-64.o.bz2: Likewise. + * testfile-vars-gcc-dwarf4-32.o.bz2: Likewise. + * testfile-vars-gcc-dwarf4-64.o.bz2: Likewise. + * testfile-vars-gcc-dwarf5-32.o.bz2: Likewise. + * testfile-vars-gcc-dwarf5-64.o.bz2: Likewise. + * Makefile.am (EXTRA_DIST): Add new test and test files. + (TESTS): Add run-varlocs-vars.sh. + 2021-09-09 Mark Wielaard * debuginfod-subr.sh: set -o functrace. diff --git a/tests/Makefile.am b/tests/Makefile.am index c586422e2..229427336 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -143,7 +143,7 @@ TESTS = run-arextract.sh run-arsymtest.sh run-ar.sh newfile test-nlist \ run-dwfl-report-elf-align.sh run-addr2line-test.sh \ run-addr2line-i-test.sh run-addr2line-i-lex-test.sh \ run-addr2line-i-demangle-test.sh run-addr2line-alt-debugpath.sh \ - run-varlocs.sh run-exprlocs.sh run-funcretval.sh \ + run-varlocs.sh run-exprlocs.sh run-varlocs-vars.sh run-funcretval.sh \ run-backtrace-native.sh run-backtrace-data.sh run-backtrace-dwarf.sh \ run-backtrace-native-biarch.sh run-backtrace-native-core.sh \ run-backtrace-native-core-biarch.sh run-backtrace-core-x86_64.sh \ @@ -399,7 +399,16 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \ testfileppc32.bz2 testfileppc64.bz2 \ testfiles390.bz2 testfiles390x.bz2 \ testfilearm.bz2 testfileaarch64.bz2 \ - run-varlocs.sh run-exprlocs.sh testfile-stridex.bz2 \ + run-varlocs.sh run-exprlocs.sh run-varlocs-vars.sh \ + testfile-vars-clang-dwarf4-32.o.bz2 \ + testfile-vars-clang-dwarf4-64.o.bz2 \ + testfile-vars-clang-dwarf5-32.o.bz2 \ + testfile-vars-clang-dwarf5-64.o.bz2 \ + testfile-vars-gcc-dwarf4-32.o.bz2 \ + testfile-vars-gcc-dwarf4-64.o.bz2 \ + testfile-vars-gcc-dwarf5-32.o.bz2 \ + testfile-vars-gcc-dwarf5-64.o.bz2 \ + testfile-stridex.bz2 \ testfile_const_type.c testfile_const_type.bz2 \ testfile_implicit_pointer.c testfile_implicit_pointer.bz2 \ testfile_parameter_ref.c testfile_parameter_ref.bz2 \ diff --git a/tests/run-varlocs-vars.sh b/tests/run-varlocs-vars.sh new file mode 100755 index 000000000..e7598bf0d --- /dev/null +++ b/tests/run-varlocs-vars.sh @@ -0,0 +1,93 @@ +#! /bin/sh +# Copyright (C) 2013, 2021 Red Hat, Inc. +# This file is part of elfutils. +# +# This file 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 3 of the License, or +# (at your option) any later version. +# +# elfutils 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, see . + +. $srcdir/test-subr.sh + +# Testfiles generated with: +# +# $ cat foo.c +# int x = 1; +# int y = 2; +# +# for cc in gcc clang; do +# for v in 4 5; do +# for w in 32 64; do +# out="testfile-vars-$cc-dwarf$v-$w.o" +# "$cc" -m"$w" -Wall -Wextra -gdwarf-"$v" -c foo.c -o "$out" +# done +# done +# done + +testfiles testfile-vars-clang-dwarf4-32.o +testfiles testfile-vars-clang-dwarf4-64.o +testfiles testfile-vars-clang-dwarf5-32.o +testfiles testfile-vars-clang-dwarf5-64.o +testfiles testfile-vars-gcc-dwarf4-32.o +testfiles testfile-vars-gcc-dwarf4-64.o +testfiles testfile-vars-gcc-dwarf5-32.o +testfiles testfile-vars-gcc-dwarf5-64.o + +tempfiles varlocs.out +testrun ${abs_top_builddir}/tests/varlocs --debug --exprlocs -e testfile-vars-clang-dwarf4-32.o | grep exprloc > varlocs.out +diff -u varlocs.out - < varlocs.out +diff -u varlocs.out - < varlocs.out +diff -u varlocs.out - < varlocs.out +diff -u varlocs.out - < varlocs.out +diff -u varlocs.out - < varlocs.out +diff -u varlocs.out - < varlocs.out +diff -u varlocs.out - < varlocs.out +diff -u varlocs.out - <