From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2205) id 237B738582BE; Fri, 8 Jul 2022 13:56:10 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 237B738582BE Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable From: Tom de Vries To: gdb-cvs@sourceware.org Subject: [binutils-gdb] [gdb/symtab] Fix segfault in dwarf2_per_objfile::symtab_set_p X-Act-Checkin: binutils-gdb X-Git-Author: Tom de Vries X-Git-Refname: refs/heads/master X-Git-Oldrev: 44ca285b73b68f6a8fa3e89004b510d6b7d98e91 X-Git-Newrev: 3fa23bb5a5320dd82d32455036d59a026929fc2f Message-Id: <20220708135610.237B738582BE@sourceware.org> Date: Fri, 8 Jul 2022 13:56:10 +0000 (GMT) X-BeenThere: gdb-cvs@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 08 Jul 2022 13:56:10 -0000 https://sourceware.org/git/gitweb.cgi?p=3Dbinutils-gdb.git;h=3D3fa23bb5a532= 0dd82d32455036d59a026929fc2f commit 3fa23bb5a5320dd82d32455036d59a026929fc2f Author: Tom de Vries Date: Fri Jul 8 15:56:06 2022 +0200 [gdb/symtab] Fix segfault in dwarf2_per_objfile::symtab_set_p =20 When running test-case gdb.cp/cpexprs-debug-types.exp with target board cc-with-debug-names, I run into: ... (gdb) print base::operator new^M ^M ^M Fatal signal: Segmentation fault^M ----- Backtrace -----^M 0x57ea46 gdb_internal_backtrace_1^M /home/vries/gdb_versions/devel/src/gdb/bt-utils.c:122^M 0x57eae9 _Z22gdb_internal_backtracev^M /home/vries/gdb_versions/devel/src/gdb/bt-utils.c:168^M 0x75b8ad handle_fatal_signal^M /home/vries/gdb_versions/devel/src/gdb/event-top.c:946^M 0x75ba19 handle_sigsegv^M /home/vries/gdb_versions/devel/src/gdb/event-top.c:1019^M 0x7f795f46a8bf ???^M 0x6d3cb1 _ZNK18dwarf2_per_objfile12symtab_set_pEPK18dwarf2_per_cu_data^M /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:1515^M ... =20 The problem is in this piece of code in dw2_debug_names_iterator::next: ... case DW_IDX_type_unit: /* Don't crash on bad data. */ if (ull >=3D per_bfd->tu_stats.nr_tus) { complaint (_(".debug_names entry has bad TU index %s" " [in module %s]"), pulongest (ull), objfile_name (objfile)); continue; } per_cu =3D per_bfd->get_cu (ull + per_bfd->tu_stats.nr_tus); break; ... =20 The all_comp_units vector (which get_cu accesses) contains both CUs and= TUs, with CUs first. =20 So to get the nth TU we need the element at "nr_cus + n", but the code uses "nr_tus + n" instead. =20 Fix this by using "nr_cus + n". =20 Tested on x86_64-linux. =20 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=3D29334 Diff: --- gdb/dwarf2/read.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c index 23fe5679cbd..9f92b420645 100644 --- a/gdb/dwarf2/read.c +++ b/gdb/dwarf2/read.c @@ -4991,7 +4991,11 @@ dw2_debug_names_iterator::next () objfile_name (objfile)); continue; } - per_cu =3D per_bfd->get_cu (ull + per_bfd->tu_stats.nr_tus); + { + int nr_cus =3D (per_bfd->all_comp_units.size () + - per_bfd->tu_stats.nr_tus); + per_cu =3D per_bfd->get_cu (nr_cus + ull); + } break; case DW_IDX_die_offset: /* In a per-CU index (as opposed to a per-module index), index