From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19840 invoked by alias); 21 Mar 2014 16:48:18 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 19761 invoked by uid 89); 21 Mar 2014 16:48:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.8 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 21 Mar 2014 16:48:16 +0000 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s2LGmFgg021461 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 21 Mar 2014 12:48:15 -0400 Received: from valrhona.uglyboxes.com (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s2LGmD0q030016 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO) for ; Fri, 21 Mar 2014 12:48:14 -0400 Message-ID: <532C6D4D.2050705@redhat.com> Date: Fri, 21 Mar 2014 16:48:00 -0000 From: Keith Seitz User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: "gdb-patches@sourceware.org ml" Subject: [RFA] Fix gdb/15827 (crash w/corrupt DWARF) Content-Type: multipart/mixed; boundary="------------090207050009070308090901" X-IsSubscribed: yes X-SW-Source: 2014-03/txt/msg00526.txt.bz2 This is a multi-part message in MIME format. --------------090207050009070308090901 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-length: 1961 Hi, I think most of us know that the dwarf2read.c pretty much assumes that the DWARF input is okay. The reporter of this bug used a binary fuzzer to corrupt the DWARF info: <1><569>: Abbrev Number: 16 (DW_TAG_enumeration_type) <56a> DW_AT_byte_size : 4 <56b> DW_AT_decl_file : 17 <56c> DW_AT_decl_line : 73 <56d> DW_AT_sibling : <0xb12> <2><571>: Abbrev Number: 17 (DW_TAG_enumerator) <572> DW_AT_name : (indirect string, offset: 0xf14): _SC_ARG_MAX <576> DW_AT_const_value : 0 [snip] <2>: Abbrev Number: 17 (DW_TAG_enumerator) DW_AT_name : (indirect string, offset: 0x9b7): _SC_LEVEL3_CACHE_ASSOC DW_AT_const_value : 2243 <2>: Abbrev Number: 12 (DW_TAG_array_type) DW_AT_type : <0x114> DW_AT_sibling : <0x761101c4> <3>: Abbrev Number: 10 (DW_TAG_member) DW_AT_name : (indirect string, offset: 0x1c50000): DW_AT_decl_file : 17 DW_AT_decl_line : 2539 DW_AT_type : <0x1c60000> DW_AT_data_member_location: 17 As you can see, the sibling for DIE 0xa93 points of to la-la land. This causes skip_one_die to crash, since it never validates whether the offset of the sibling is contained within the current readers's input buffer. This function does check, however, whether the offset is negative. This patch essentially adds the counterpoint check and a beginning at some tests for catch-all "corrupt" DWARF. Keith ChangeLog 2014-03-20 Keith Seitz PR gdb/15827 * dwarf2read.c (skip_one_die): Check that all relative-offset sibling DIEs fall within range of the current reader's buffer. (read_partial_die): Likewise. testsuite/ChangeLog 2014-03-20 Keith Seitz PR gdb/15827 * gdb.dwarf2/corrupt.c: New file. * gdb.dwarf2/corrupt.exp: New file. --------------090207050009070308090901 Content-Type: text/x-patch; name="15827.patch" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="15827.patch" Content-length: 4037 diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c index 705dc2d..c30b1b3 100644 --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -7103,6 +7103,8 @@ skip_one_die (const struct die_reader_specs *reader, const gdb_byte *info_ptr, if (sibling_ptr < info_ptr) complaint (&symfile_complaints, _("DW_AT_sibling points backwards")); + else if (sibling_ptr > reader->buffer_end) + dwarf2_section_buffer_overflow_complaint (reader->die_section); else return sibling_ptr; } @@ -15416,6 +15418,8 @@ read_partial_die (const struct die_reader_specs *reader, if (sibling_ptr < info_ptr) complaint (&symfile_complaints, _("DW_AT_sibling points backwards")); + else if (sibling_ptr > reader->buffer_end) + dwarf2_section_buffer_overflow_complaint (reader->die_section); else part_die->sibling = sibling_ptr; } diff --git a/gdb/testsuite/gdb.dwarf2/corrupt.c b/gdb/testsuite/gdb.dwarf2/corrupt.c new file mode 100644 index 0000000..4120f3d --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/corrupt.c @@ -0,0 +1,24 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2014 Free Software Foundation, Inc. + + 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 3 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, see . */ + +/* Dummy main function. */ + +int +main() +{ + return 0; +} diff --git a/gdb/testsuite/gdb.dwarf2/corrupt.exp b/gdb/testsuite/gdb.dwarf2/corrupt.exp new file mode 100644 index 0000000..ba5e551 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/corrupt.exp @@ -0,0 +1,78 @@ +# Copyright 2014 Free Software Foundation, Inc. + +# 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 3 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, see . + +# Test corrupt DWARF input +# PR gdb/15827 + +load_lib dwarf.exp + +if {![dwarf2_support]} { + return 0 +} + +standard_testfile corrupt.c corrupt.S + +# Make the DWARF used for the test. +# +# Here we put DW_AT_sibling DIEs into the output which +# point off into la-la land. The whole purpose is to simulate +# corrupt DWARF information and make sure that GDB can handle it +# without crashing. + +set asm_file [standard_output_file $srcfile2] +Dwarf::assemble $asm_file { + cu {} { + compile_unit {} { + declare_labels int_label + + int_label: base_type { + {byte_size 4} + {name "int"} + } + + enumeration_type { + {name "ENUM"} + {byte_size 4} + } { + enumerator { + {name "A"} + {const_value 0} + } + enumerator { + {name "B"} + {const_value 1} + {sibling 12345678 DW_FORM_ref4} + } { + base_type { + {byte_size 1} + {name "char"} + } + } + array_type { + {type :$int_label} + {sibling 12345678 DW_FORM_ref4} + } + } + } + } +} + +if {[prepare_for_testing $testfile.exp $testfile \ + [list $srcfile $asm_file] {nodebug}]} { + return -1 +} + +# If we get here and gdb hasn't crashed, the tests pass. +pass "corrupt DWARF" --------------090207050009070308090901--