Bug 821129
| Summary: | [abrt] bash-4.2.28-1.fc16: __GI___libc_free: Process /bin/bash was killed by signal 11 (SIGSEGV) | ||||||||
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| Product: | [Fedora] Fedora | Reporter: | Jerzy Spendel <jspendel> | ||||||
| Component: | bash | Assignee: | Roman Rakus <rrakus> | ||||||
| Status: | CLOSED WONTFIX | QA Contact: | Fedora Extras Quality Assurance <extras-qa> | ||||||
| Severity: | unspecified | Docs Contact: | |||||||
| Priority: | unspecified | ||||||||
| Version: | 16 | CC: | maxamillion, pmachata, rrakus, tsmetana | ||||||
| Target Milestone: | --- | ||||||||
| Target Release: | --- | ||||||||
| Hardware: | x86_64 | ||||||||
| OS: | Unspecified | ||||||||
| Whiteboard: | abrt_hash:0573462398fb7f9b6dfc90935a45a474f04e5a8e | ||||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||||
| Doc Text: | Story Points: | --- | |||||||
| Clone Of: | Environment: | ||||||||
| Last Closed: | 2013-02-13 21:40:59 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: | |||||||||
| Attachments: |
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Description
Jerzy Spendel
2012-05-12 10:04:30 UTC
Created attachment 583971 [details]
File: coredump
Created attachment 583972 [details]
File: backtrace
The chain of released commands lists two nested for's, and one simple command, on lines 6529, 6583 and 6947 respectively. There's an if between for and simple command, but its test and true branch were destroyed already, and carry no useful data. There's also a bunch of connectors in between. I tried to find a libtool script that matches these criteria, but they all seem to be off by 3 lines. Roman, do you have any idea why this would be? Maybe it's just some sort of systematic offset. In any case, the line in question seems to be: > test "X$hardcode_automatic" = Xyes && avoidtemprpath=yes The first word is where it fails. The remaining words in the list (up until &&, where the command ends) are intact, but the word "test" is mangled: > $224 = {word = 0x1c08dd0 "\340\253\275\001", flags = 0} This is certainly neither ASCII, nor UTF-8. All the released words seem to look approximately like this, could it be a double free? When we enter glibc, the free pretty much does several tests that turn out false (which we know, because all the true branches end in return), then converts the buffer to a malloc chunk (offset by 16 bytes), which looks like this: > $225 = {prev_size = 0, size = 8030604385476149252, fd = 0x1bdabe0, > bk = 0x1c08df0, fd_nextsize = 0x0, bk_nextsize = 0x21} That size is suspicious: >>> hex(8030604385476149252) 0x6f72702400000004 That says: >>> '\x04\x00\x00\x00$pro' Needless to say, libtool is full of "$pro" substrings. A buffer overrun? A reused chunk? Uninitialized memory? Who knows. I'll look into it some more. Jerzy Spendel, could you please tell us what version of libtool you are using? Was it altered in any way (try rpm -qV libtool). This could help us reproduce the problem locally and then fix it. I looked into the allocator, but the free function is quite straightforward, just a bit of masking. (_int_free is another story, but it fails before reaching it.) The area of memory that starts at "fd" double-serves as malloced buffer (if it's allocated) and service area (if it's freed). In this case, fd and bk hold what looks like valid heap pointers. That might mean that the block was already freed once, or that it was freed, later malloced again, but not initialized. I don't see a way to determine who mangled the size field without some sort of reproducer. But my attempts at reproducing this bug have been futile so far, I'm afraid that without the exact same libtool and the exact same .lo's and .la's, we simply won't be able to trick bash into triggering this error. In particular, valgrind doesn't complain when I run libtool on my mock project. Jerzy Spendel, could you please tell us what version of libtool you are using? Was it altered in any way (try rpm -qV libtool). This could help us reproduce the problem locally and then fix it. Can you please also provide us any reproducer? I'm really sorry i haven't replied for long time...My libtool version is 2.4-9 rpm -qV libtool didn't return anything This message is a reminder that Fedora 16 is nearing its end of life. Approximately 4 (four) weeks from now Fedora will stop maintaining and issuing updates for Fedora 16. It is Fedora's policy to close all bug reports from releases that are no longer maintained. At that time this bug will be closed as WONTFIX if it remains open with a Fedora 'version' of '16'. Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, simply change the 'version' to a later Fedora version prior to Fedora 16's end of life. Bug Reporter: Thank you for reporting this issue and we are sorry that we may not be able to fix it before Fedora 16 is end of life. If you would still like to see this bug fixed and are able to reproduce it against a later version of Fedora, you are encouraged to click on "Clone This Bug" and open it against that version of Fedora. Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Fedora release includes newer upstream software that fixes bugs or makes them obsolete. The process we are following is described here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping Fedora 16 changed to end-of-life (EOL) status on 2013-02-12. Fedora 16 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. Thank you for reporting this bug and we are sorry it could not be fixed. |