Bug 755242
| Summary: | wcscmp() triggers valgrind warnings | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Sam Varshavchik <mrsam> |
| Component: | valgrind | Assignee: | Mark Wielaard <mjw> |
| Status: | CLOSED ERRATA | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | low | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 18 | CC: | dodji, jakub, kjell, mjw, paul.0000.black |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2012-12-20 16:02:57 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Seeing the same; doesn't happen with a 32-bit prog on 64-bit F16. Posted bug and patch upstream: SSE optimized wcscpy, wcscmp, wcsrchr and wcschr trigger uninitialised value and/or invalid read warnings https://bugs.kde.org/show_bug.cgi?id=307828 valgrind-3.8.1-3.fc18 has been submitted as an update for Fedora 18. https://admin.fedoraproject.org/updates/valgrind-3.8.1-3.fc18 Package valgrind-3.8.1-3.fc18: * should fix your issue, * was pushed to the Fedora 18 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing valgrind-3.8.1-3.fc18' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2012-16133/valgrind-3.8.1-3.fc18 then log in and leave karma (feedback). valgrind-3.8.1-3.fc17 has been submitted as an update for Fedora 17. https://admin.fedoraproject.org/updates/valgrind-3.8.1-3.fc17 valgrind-3.8.1-3.fc17 fails. [mrsam@octopus base]$ valgrind --tool=memcheck ./testhttpclientauth ==28524== Memcheck, a memory error detector ==28524== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al. ==28524== Using Valgrind-3.8.1 and LibVEX; rerun with -h for copyright info ==28524== Command: ./testhttpclientauth ==28524== vex amd64->IR: unhandled instruction bytes: 0xF0 0xF 0xC0 0x10 0x84 0xD2 0xF 0x95 vex amd64->IR: REX=0 REX.W=0 REX.R=0 REX.X=0 REX.B=0 vex amd64->IR: VEX=0 VEX.L=0 VEX.nVVVV=0x0 ESC=0F vex amd64->IR: PFX.66=0 PFX.F2=0 PFX.F3=0 ==28524== valgrind: Unrecognised instruction at address 0x56c947. valgrind-3.7.0-4.fc17.x86_64 works on this binary (except for this bug). (In reply to comment #6) > valgrind-3.8.1-3.fc17 fails. > > [mrsam@octopus base]$ valgrind --tool=memcheck ./testhttpclientauth > ==28524== Memcheck, a memory error detector > ==28524== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al. > ==28524== Using Valgrind-3.8.1 and LibVEX; rerun with -h for copyright info > ==28524== Command: ./testhttpclientauth > ==28524== > vex amd64->IR: unhandled instruction bytes: 0xF0 0xF 0xC0 0x10 0x84 0xD2 0xF > 0x95 > vex amd64->IR: REX=0 REX.W=0 REX.R=0 REX.X=0 REX.B=0 > vex amd64->IR: VEX=0 VEX.L=0 VEX.nVVVV=0x0 ESC=0F > vex amd64->IR: PFX.66=0 PFX.F2=0 PFX.F3=0 > ==28524== valgrind: Unrecognised instruction at address 0x56c947. > > valgrind-3.7.0-4.fc17.x86_64 works on this binary (except for this bug). I'll open a new bug for this, since this is a different, but probably new, issue. Could you share the binary or share the build instructions? (In reply to comment #7) > I'll open a new bug for this, since this is a different, but probably new, > issue. https://bugzilla.redhat.com/show_bug.cgi?id=866793 valgrind-3.8.1-4.fc17 has been pushed to the Fedora 17 stable repository. If problems still persist, please make note of it in this bug report. |
Description of problem: wcscmp() in glibc glibc-2.14 (at least on x86_64) uses MMX, that may read past the end of the input strings it's checking. valgrind doesn't like this. Version-Release number of selected component (if applicable): valgrind-3.6.1-6.fc16.x86_64 How reproducible: Always Steps to Reproduce: 1. #include <wchar.h> void foo(int) { } int main() { wchar_t *a=new wchar_t[2], *b=new wchar_t[2]; size_t j; a[0]=b[0]='A'; a[1]=b[1]=0; foo(wcscmp(a, b)); delete[] a; delete[] b; return 0; } 2. valgrind --tool=memcheck --leak-check=yes <program> Actual results: ==9488== Invalid read of size 8 ==9488== at 0x384069F280: wcscmp (wcscmp.S:423) ==9488== by 0x400643: main (t.C:15) ==9488== Address 0x4c2b048 is 0 bytes after a block of size 8 alloc'd ==9488== at 0x4A06A27: operator new[](unsigned long) (vg_replace_malloc.c:305) ==9488== by 0x4005EE: main (t.C:9) Expected results: No warnings. Additional info: Add to /usr/lib64/valgrind/default.supp: { wcscmp-uses-mmx Memcheck:Addr8 fun:wcscmp }