https://sourceware.org/bugzilla/show_bug.cgi?id=28658
Bug ID: 28658 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: --- 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='-g -O1 -fno-omit-frame-pointer' --enable-sanitize-undefined CXXFLAGS='-g -O1 -fno-omit-frame-pointer' make -j$(nproc) V=1 LD_PRELOAD="./libelf/libelf.so ./libdw/libdw.so" UBSAN_OPTIONS=print_stacktrace=1:print_summary=1 ./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=41574 ``` Running: /mnt/scratch0/clusterfuzz/bot/inputs/fuzzer-testcases/crash-747fcf4f5bf93741e8fc31e9cbb44a70865e4c07 link_map.c:873:12: runtime error: division by zero #0 0x51cae6 in dwfl_link_map_report /src/elfutils/libdwfl/link_map.c:873:12 #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 ``` -- You are receiving this mail because: You are on the CC list for the bug.