Bug 911110

Summary: krb5_get_init_creds_keytab() leaks memory
Product: [Fedora] Fedora Reporter: Petr Spacek <pspacek>
Component: krb5Assignee: Nalin Dahyabhai <nalin>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 17CC: nalin, nathaniel, pspacek
Target Milestone: ---   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: krb5-1.10.2-8.fc17 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of:
: 911147 (view as bug list) Environment:
Last Closed: 2013-03-16 01:31:08 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 911147    
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Description Flags
proposed patch none

Description Petr Spacek 2013-02-14 12:16:30 UTC 
Description of problem:
Function lookup_etypes_for_keytab() in krb5-libs leaks memory while working with keytab.


Version-Release number of selected component (if applicable):
krb5-libs-1.10.2-6.fc17.x86_64


How reproducible:
100 %


Steps to Reproduce:
1. Create program with krb5_get_init_creds_keytab()
2. Call the program on keytab file with big amount of amount of keys
3. Use valgrind to check your program


Actual results:
Output from Valgrind.
==8048==    at 0x4A0881C: malloc (vg_replace_malloc.c:270)
==8048==    by 0x58A9F5B: krb5_ktfileint_internal_read_entry.isra.5 (kt_file.c:1253)
==8048==    by 0x58AA7BE: krb5_ktfile_get_next (kt_file.c:1414)
==8048==    by 0x58BCF4C: krb5_init_creds_set_keytab (gic_keytab.c:101)
==8048==    by 0x58BD25D: get_init_creds_keytab (gic_keytab.c:229)
==8048==    by 0x58BD377: krb5_get_init_creds_keytab (gic_keytab.c:271)
==8048==    by 0xC2477F9: get_krb5_tgt (krb5_helper.c:176)


Expected results:
No leaks :-)


Additional info:
AFAIK the memory leak originates in lookup_etypes_for_keytab() function. File gic_keytab.c:101 contains krb5_kt_next_entry() call in a loop, but there is no krb5_kt_free_entry() call in this loop.

See code example in manual page http://www.unix.com/man-page/all/3/krb5_kt_free_entry/
Comment 1 Nalin Dahyabhai 2013-02-28 20:37:17 UTC 
(In reply to comment #0)> AFAIK the memory leak originates in lookup_etypes_for_keytab() function.
> File gic_keytab.c:101 contains krb5_kt_next_entry() call in a loop, but
> there is no krb5_kt_free_entry() call in this loop.

Looks like you're right: there's supposed to be some krb5_free_keytab_entry_contents() action in there.
Comment 2 Nalin Dahyabhai 2013-02-28 20:41:35 UTC 
Created attachment 703982 [details]
proposed patch
Comment 3 Petr Spacek 2013-03-04 11:34:19 UTC 
krb5-1.10.2-8.fc17 fixed the problem on my system, thank you!
Comment 4 Fedora Update System 2013-03-05 18:43:59 UTC 
krb5-1.10.2-9.fc17 has been submitted as an update for Fedora 17.
https://admin.fedoraproject.org/updates/FEDORA-2013-3116/krb5-1.10.2-9.fc17
Comment 5 Fedora Update System 2013-03-05 18:44:18 UTC 
krb5-1.10.3-14.fc18 has been submitted as an update for Fedora 18.
https://admin.fedoraproject.org/updates/FEDORA-2013-3147/krb5-1.10.3-14.fc18
Comment 6 Fedora Update System 2013-03-05 18:45:39 UTC 
krb5-1.10.2-9.fc17 has been submitted as an update for Fedora 17.
https://admin.fedoraproject.org/updates/FEDORA-2013-3116/krb5-1.10.2-9.fc17
Comment 7 Fedora Update System 2013-03-06 23:03:52 UTC 
Package krb5-1.10.3-14.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 krb5-1.10.3-14.fc18'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2013-3147/krb5-1.10.3-14.fc18
then log in and leave karma (feedback).
Comment 8 Fedora Update System 2013-03-16 01:31:10 UTC 
krb5-1.10.2-9.fc17 has been pushed to the Fedora 17 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 9 Fedora Update System 2013-03-22 21:07:58 UTC 
krb5-1.10.3-14.fc18 has been pushed to the Fedora 18 stable repository.  If problems still persist, please make note of it in this bug report.