Bug 191783
| Summary: | pdksh core dumps | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 2.1 | Reporter: | Kurtis Rader <kdrader> | ||||||
| Component: | pdksh | Assignee: | Karsten Hopp <karsten> | ||||||
| Status: | CLOSED WONTFIX | QA Contact: | |||||||
| Severity: | high | Docs Contact: | |||||||
| Priority: | medium | ||||||||
| Version: | 2.1 | CC: | tao | ||||||
| Target Milestone: | --- | ||||||||
| Target Release: | --- | ||||||||
| Hardware: | All | ||||||||
| OS: | Linux | ||||||||
| Whiteboard: | |||||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||||
| Doc Text: | Story Points: | --- | |||||||
| Clone Of: | Environment: | ||||||||
| Last Closed: | 2007-01-10 11:46:08 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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Created attachment 129109 [details]
files and scripts to reproduce the failure
It has been found that the pdksh allocation test harness can be used to produce
a failure that may be related to this problem.
1.download and extract source of pdksh.
I used pdksh-5.2.14-21.
2.make "TEST_ALLOC" tool in alloc.c
% cd pdksh-5.2.14-21
% ./configure
% gcc -o test_alloc -DTEST_ALLOC=1 -DDEBUG_ALLOC=1 -O2 alloc.c
3.run test_alloc and test("INPUT>" means input contents to pdksh)
% ./test_alloc
INPUT > alloc 800 = i1
OUTPUT> 0x804b028 = alloc(800) 1,i1
INPUT > alloc 792 = i2
OUTPUT> 0x804b358 = alloc(792) 2,i2
INPUT > alloc 10 = i3
OUTPUT> 0x804b680 = alloc(10) 3,i3
INPUT > aprint 0
OUTPUT> aprint(0, 0) 4
OUTPUT> aprint: block 0 (p=0x804b008,0x804b008,n=0x804b008): 0x0x804b018 ..
OUTPUT> 0x0x804b988 (2416)
OUTPUT> aprint: 0x0x804b018 .. 0x0x804b348 (816) allocated
OUTPUT> aprint: 0x0x804b348 .. 0x0x804b670 (808) allocated
OUTPUT> aprint: 0x0x804b670 .. 0x0x804b690 (32) allocated
OUTPUT> aprint: 0x0x804b690 .. 0x0x804b988 (760) free
INPUT > afree i1
OUTPUT> afree(0x804b028) 5,i1
INPUT > afree i2
OUTPUT> afree(0x804b358) 6,i2
INPUT > aprint 0
OUTPUT> aprint(0, 0) 7
OUTPUT> aprint: block 0 (p=0x804b008,0x804b008,n=0x804b008):
0x0x804b018 ..
0x0x804b988 (2416)
OUTPUT> aprint: 0x0x804b018 .. 0x0x804b670 (1624) free
OUTPUT> aprint: 0x0x804b670 .. 0x0x804b690 (32) allocated
OUTPUT> aprint: 0x0x804b690 .. 0x0x804b988 (760) free
INPUT > alloc 1591 = i4
OUTPUT> acheck: big cell doesn't make up whole block
OUTPUT> aerror: acheck failed
I backported a patch from Debian that replaces the wacky allocation scheme that pdksh uses with a much more simple and sane one. It seems to fix the problem in my testing...I am going to attach the patch here, and put RPMS here: http://people.redhat.com/clalance/pdksh.html I only put up the i386 package and the source RPM. NOTE: this patch has not yet been blessed by the pdksh maintainer. That means these packages are for testing only, and does not guarantee anything. Also, given the maintenance status of 2.1, I don't know if it will ever make an update. But it will be more convincing if there is testing (beyond my own) to back up the patch. Created attachment 130274 [details]
Replace pdksh cell based allocation with linked list
(In reply to comment #4) > Created an attachment (id=130274) [edit] > Replace pdksh cell based allocation with linked list > Resolves problem for me. |
Description of problem: pdksh will die from a SIGSEGV under some circumstances. Version-Release number of selected component (if applicable): pdksh 5.2.14-22 How reproducible: Can be reproduced on demand given proper initial conditions. However, the problem is extremely sensitive to the initial conditions and therefore difficult to reproduce in an arbitrary environment. Problem has been observed on RHEL 2.1 and RHEL 3 (not surprising since they have the same version of pdksh). However, I have been unable to reproduce the problem on RHEL 3 using the exact same reproduction steps; not even with exec-shield and exec-shield- randomize disabled. Steps to Reproduce: 1. Unpack the attachment with cwd == / 2. ./pdksh_segv Actual results: ./pdksh_segv: line 27: 27597 Segmentation fault Expected results: Script runs to completion Additional info: From a version of pdksh built with "-g": Core was generated by `/home/root/pdksh.dbg ./exec_java.csh AAA BBB CCC DDD'. Program terminated with signal 11, Segmentation fault. Reading symbols from /lib/i686/libc.so.6...done. Loaded symbols for /lib/i686/libc.so.6 Reading symbols from /lib/ld-linux.so.2...done. Loaded symbols for /lib/ld-linux.so.2 #0 ablockfree (bp=0x5f6f796e, ap=0x8074dc8) at alloc.c:475 475 if (bp->next == bp) /* only block */ (gdb) bt #0 ablockfree (bp=0x5f6f796e, ap=0x8074dc8) at alloc.c:475 #1 0x08067ac4 in setstr (vq=0x807d5b8, s=0x807d000 "/xxx/lib//app_e_kofu.jar", error_ok=0) at var.c:372 #2 0x08055745 in execute (t=0x807b248, flags=0) at exec.c:332 #3 0x0805f6f7 in shell (s=0x8079d28, toplevel=1) at main.c:616 #4 0x0805f2c8 in main (argc=4, argv=0xbffed244) at main.c:429