Bug 114618

Summary:

pthread_attr_destroy reports free(): invalid pointer

Product:

Red Hat Enterprise Linux 3

Reporter:

Ivan Loncar <ivan.loncar>

Component:

glibc

Assignee:

Jakub Jelinek <jakub>

Status:

CLOSED NOTABUG

QA Contact:

Brian Brock <bbrock>

Severity:

high

Docs Contact:

Priority:

medium

Version:

3.0

Target Milestone:

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Target Release:

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Hardware:

i386

OS:

Linux

Whiteboard:

Fixed In Version:

Doc Type:

Bug Fix

Doc Text:

Story Points:

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Clone Of:

Environment:

Last Closed:

2004-01-30 09:06:43 UTC

Type:

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Regression:

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Mount Type:

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Documentation:

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CRM:

Verified Versions:

Category:

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oVirt Team:

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RHEL 7.3 requirements from Atomic Host:

Cloudforms Team:

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Target Upstream Version:

Embargoed:

Attachments:

Description	Flags
sample libmylib.so source	none
Sample program mythrtest	none
sample libmy2lib.so source	none
Sample program mythrtest2	none

Description Ivan Loncar 2004-01-30 08:09:54 UTC

Description of problem:
Attached programs report errors.

Version-Release number of selected component (if applicable):
glibc-2.3.2-95.3

How reproducible:
Everytime.

Steps to Reproduce:
1. copy sample sources to a temp dir and cd to that dir 
2. export LD_LIBRARY_PATH=`pwd`
3. cc -D__USE_POSIX -D__REENTRANT -fpic -g -I. -c mylib.c -o mylib.o
4. ld -shared -o libmylib.so mylib.o
5. cc -D__USE_POSIX -D__REENTRANT -fpic -g -I. -c my2lib.c -o my2lib.o
6. ld -shared -o libmy2lib.so my2lib.o
7. gcc -o mythrtest mythrtest.c -L`pwd` -lmylib -lpthread
8. gcc -o mythrtest2 mythrtest2.c -L`pwd` -lmy2lib -lpthread
9. execute both binaries:
  # ./mythrtest
  # ./mythrtest2

  
Actual results:
free(): invalid pointer 0xbfffba48!
   or
Segmentation fault

Expected results:
No errors

Additional info:
Quick look at the glibc sources suggests that some members of 
pthread_attr_t are not initialized, which leads to freeing wild 
pointer.

Comment 1 Ivan Loncar 2004-01-30 08:14:28 UTC

Created attachment 97361 [details]
sample libmylib.so source

cc -D__USE_POSIX -D__REENTRANT -fpic -g -I. -c mylib.c -o mylib.o
ld -shared -o libmylib.so mylib.o

Comment 2 Ivan Loncar 2004-01-30 08:16:04 UTC

Created attachment 97362 [details]
Sample program mythrtest

gcc -o mythrtest mythrtest.c -L`pwd` -lmylib -lpthread

Comment 3 Ivan Loncar 2004-01-30 08:17:01 UTC

Created attachment 97363 [details]
sample libmy2lib.so source

cc -D__USE_POSIX -D__REENTRANT -fpic -g -I. -c my2lib.c -o my2lib.o
ld -shared -o libmy2lib.so my2lib.o

Comment 4 Ivan Loncar 2004-01-30 08:18:24 UTC

Created attachment 97364 [details]
Sample program mythrtest2

gcc -o mythrtest2 mythrtest2.c -L`pwd` -lmy2lib -lpthread

Comment 5 Jakub Jelinek 2004-01-30 09:06:43 UTC

There are 2 very serious bugs in your testcase:
1) never ever use ld -shared directly, always use gcc -shared or g++ -shared
   The GCC driver knows the details how to link properly shared libraries
   on each platform, which is certainly not simply running ld -shared
2) if you use any pthread functions in a library which don't have also
   stubs in libc.so (this is the case of mylib.c, but not my2lib.c),
   then you absolutely must link with -lpthread, otherwise symbol
   versioning cannot work properly
If you do this, your testcase will work just fine.
There was a bug in libpthread.so when handling libraries built against
glibc 2.0, fixed in glibc-2.3.2-95.7, which will cure also your incorrectly
built testcase, but that doesn't mean linking things this way will not
malfunction in other places (it will).
glibc-2.3.2-95.7 (well, one of its successors) will show up in U2, but
closing as a NOTABUG, since this is primarily because of a buggy testcase.