From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 4518D3858C60; Mon, 6 Dec 2021 12:46:16 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 4518D3858C60 From: "evvers at ya dot ru" To: elfutils-devel@sourceware.org Subject: [Bug libdw/28657] New: UBSan seems to report a divison-by-zero in dwfl_link_map_report Date: Mon, 06 Dec 2021 12:46:16 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: elfutils X-Bugzilla-Component: libdw X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: evvers at ya dot ru X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter cc target_milestone attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: elfutils-devel@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Elfutils-devel mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Dec 2021 12:46:16 -0000 https://sourceware.org/bugzilla/show_bug.cgi?id=3D28657 Bug ID: 28657 Summary: UBSan seems to report a divison-by-zero in dwfl_link_map_report Product: elfutils Version: unspecified Status: UNCONFIRMED Severity: normal Priority: P2 Component: libdw Assignee: unassigned at sourceware dot org Reporter: evvers at ya dot ru CC: elfutils-devel at sourceware dot org Target Milestone: --- Created attachment 13824 --> https://sourceware.org/bugzilla/attachment.cgi?id=3D13824&action=3Ded= it File triggering a "division-by-zero" One of systemd fuzz target run under UBSan discovered a "divison-by-zero". = It can be reproduced by building the master branch of the elfutils repository = with UBSan and passing the attachment to `./src/stack` ``` $ git describe elfutils-0.186-7-g99782bd2 autoreconf -i -f ./configure --enable-maintainer-mode CFLAGS=3D'-g -O1 -fno-omit-frame-point= er' --enable-sanitize-undefined CXXFLAGS=3D'-g -O1 -fno-omit-frame-pointer' make -j$(nproc) V=3D1 LD_PRELOAD=3D"./libelf/libelf.so ./libdw/libdw.so" UBSAN_OPTIONS=3Dprint_stacktrace=3D1:print_summary=3D1 ./src/stack --core ../oss-fuzz-41574 link_map.c:873:12: runtime error: division by zero #0 0x7f93972cf29a in dwfl_link_map_report /home/vagrant/elfutils/libdwfl/link_map.c:873 #1 0x7f93972d25c7 in _new.dwfl_core_file_report /home/vagrant/elfutils/libdwfl/core-file.c:548 #2 0x402b0f in parse_opt /home/vagrant/elfutils/src/stack.c:595 #3 0x7f939654df81 in __argp_parse (/lib64/libc.so.6+0x10cf81) #4 0x403d98 in main /home/vagrant/elfutils/src/stack.c:695 #5 0x7f9396468b74 in __libc_start_main (/lib64/libc.so.6+0x27b74) #6 0x4024cd in _start (/home/vagrant/elfutils/src/stack+0x4024cd) SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior link_map.c:873:12 in ``` It was also reported in https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=3D41574 ``` Running: /mnt/scratch0/clusterfuzz/bot/inputs/fuzzer-testcases/crash-747fcf4f5bf9374= 1e8fc31e9cbb44a70865e4c07 link_map.c:873:12: runtime error: division by zero #0 0x51cae6 in dwfl_link_map_report /src/elfutils/libdwfl/link_map.c:87= 3:12 #1 0x4b868b in dwfl_core_file_report /src/elfutils/libdwfl/core-file.c:548:16 #2 0x4b363e in LLVMFuzzerTestOneInput /src/fuzz-dwfl-core.c:52:6 #3 0x43f1b3 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) cxa_noexception.cpp:0 #4 0x42aac2 in fuzzer::RunOneTest(fuzzer::Fuzzer*, char const*, unsigned long) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:324:6 #5 0x43058a in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) cxa_noexception.cpp:0 #6 0x4594b2 in main /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:10 #7 0x7f2bedb160b2 in __libc_start_main /build/glibc-eX1tMB/glibc-2.31/csu/libc-start.c:308:16 #8 0x407d4d in _start SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior link_map.c:873:12 in ``` --=20 You are receiving this mail because: You are on the CC list for the bug.=