Bug 1570527 – memory management issue in the sssd_nss_ex interface can cause the ns-slapd process on IPA server to crash [rhel-7.5.z]

Bugzilla will be upgraded to version 5.0. The upgrade date is tentatively scheduled for 2 December 2018, pending final testing and feedback.

Bug 1570527 - memory management issue in the sssd_nss_ex interface can cause the ns-slapd process on IPA server to crash [rhel-7.5.z]

Summary:	memory management issue in the sssd_nss_ex interface can cause the ns-slapd p...

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 7
Classification:	Red Hat
Component:	sssd (Show other bugs)
Sub Component:
Version:	7.5
Hardware:	All Linux

Priority	urgent Severity urgent
Target Milestone:	rc
Target Release:	---
Assigned To:	SSSD Maintainers
QA Contact:	ipa-qe
Docs Contact:

URL:
Whiteboard:
Keywords:	ZStream

Depends On:	1566782
Blocks:
	Show dependency tree / graph

Reported:	2018-04-23 02:59 EDT by Oneata Mircea Teodor
Modified:	2018-07-30 09:54 EDT (History)
CC List:	35 users (show)

See Also:
Fixed In Version:	sssd-1.16.0-19.el7_5.1
Doc Type:	Bug Fix
Doc Text:	Previously, if a large group was requested through the sssd_nss_ex interface, the buffer used inside the SSSD had to be relocated to be able to hold all the group members. However, when SSSD wanted to free this buffer, it used the address of the original memory, not the reallocated one. Because SSSD freed the original memory address, not the new one returned by the function that reallocates the memory, the Red Hat Directory Server (RHDS) sometimes terminated unexpectedly. The reason for this is that the sssd API is called from the context of RHDS. With this update, the SSSD code has been modified to free the reallocated memory. As a result, no crash that would manifest as a crash of RHDS happens in the SSSD code.
Story Points:	---
Clone Of:	1566782
Environment:
Last Closed:	2018-06-26 12:49:19 EDT
Type:	---
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

Attachments	(Terms of Use)
Add an attachment (proposed patch, testcase, etc.)

External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHBA-2018:1986	None	None	None	2018-06-26 12:49 EDT

Groups: None (edit)

Description Oneata Mircea Teodor 2018-04-23 02:59:05 EDT

This bug has been copied from bug #1566782 and has been proposed to be backported to 7.5 z-stream (EUS).

Comment 14 Niranjan Mallapadi Raghavender 2018-06-05 05:33:19 EDT

1. Reproducing the issue:

Versions
========
sssd-1.16.0-19.el7.x86_64
libsss_nss_idmap-1.16.0-19.el7.x86_64

1. Configure sssd.conf to use ldap provider with 389-ds-base configured
as ldap server 

[sssd]
domains = EXAMPLE.TEST
config_file_version = 2
services = nss, pam, ifp

[domain/EXAMPLE.TEST]
enumerate = false
id_provider = ldap
ldap_uri = ldap://host-8-242-110.host.centralci.eng.rdu2.redhat.com
ldap_search_base = dc=example,dc=test
ldap_tls_cacert = /etc/openldap/cacerts/cacert.pem
auth_provider = krb5
krb5_server = host-8-242-110.host.centralci.eng.rdu2.redhat.com
krb5_kpasswd = host-8-242-110.host.centralci.eng.rdu2.redhat.com
krb5_realm = EXAMPLE.TEST
debug_level = 9
cache_credentials = True
krb5_store_password_if_offline = True

[nss]
debug_level = 9

[pam]
debug_level = 9
offline_credentials_expiration = 0

[secrets]
debug_level = 9

[kcm]
debug_level = 9


2. Add users in ldap foo0 who is membero of more than 10 Groups
[root@host-8-242-110 opt]# id foo0
uid=14583100(foo0) gid=14564100(ldap_group0) groups=14564100(ldap_group0),24564106(group7),24564107(group8),24564108(group9),24564105(group6),24564109(group10),24564112(group13),24564116(group17),24564118(group19),24564100(group1),24564102(group3),24564103(group4),24564110(group11),24564114(group15),24564117(group18),24564119(group20),24564101(group2),24564104(group5),24564111(group12),24564113(group14),24564115(group16)


3. Download the program as specified in https://bugzilla.redhat.com/show_bug.cgi?id=1566782#c37

4. gcc test.c -lsss_nss_idmap -o test

5. Run valgrind as shown below
valgrind ./test foo0

valgrind shows leaks as shown below:

[root@host-8-242-110 opt]# valgrind ./test foo1
==2039== Memcheck, a memory error detector
==2039== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==2039== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==2039== Command: ./test foo1
==2039==
foo1: sss_nss_getgrouplist_ex 2: No such file or directory
==2039==
==2039== HEAP SUMMARY:
==2039==     in use at exit: 0 bytes in 0 blocks
==2039==   total heap usage: 6 allocs, 6 frees, 192 bytes allocated
==2039==
==2039== All heap blocks were freed -- no leaks are possible
==2039==
==2039== For counts of detected and suppressed errors, rerun with: -v
==2039== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
[root@host-8-242-110 opt]# valgrind ./test foo0
==2044== Memcheck, a memory error detector
==2044== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==2044== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==2044== Command: ./test foo0
==2044==
==2044== Invalid read of size 8
==2044==    at 0x4C2E060: memcpy@@GLIBC_2.14 (vg_replace_strmem.c:1022)
==2044==    by 0x4E38E61: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==  Address 0x582d090 is 0 bytes inside a block of size 40 free'd
==2044==    at 0x4C2BB58: realloc (vg_replace_malloc.c:785)
==2044==    by 0x4E3C531: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E38651: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E387DA: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E38E1C: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==  Block was alloc'd at
==2044==    at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==2044==    by 0x4E38DE4: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==
==2044== Invalid read of size 8
==2044==    at 0x4C2E06E: memcpy@@GLIBC_2.14 (vg_replace_strmem.c:1022)
==2044==    by 0x4E38E61: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==  Address 0x582d0a0 is 16 bytes inside a block of size 40 free'd
==2044==    at 0x4C2BB58: realloc (vg_replace_malloc.c:785)
==2044==    by 0x4E3C531: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E38651: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E387DA: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E38E1C: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==  Block was alloc'd at
==2044==    at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==2044==    by 0x4E38DE4: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==
==2044== Invalid free() / delete / delete[] / realloc()
==2044==    at 0x4C2ACBD: free (vg_replace_malloc.c:530)
==2044==    by 0x4E38E6E: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==  Address 0x582d090 is 0 bytes inside a block of size 40 free'd
==2044==    at 0x4C2BB58: realloc (vg_replace_malloc.c:785)
==2044==    by 0x4E3C531: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E38651: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E387DA: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x4E38E1C: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==  Block was alloc'd at
==2044==    at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==2044==    by 0x4E38DE4: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==2044==    by 0x400671: main (in /opt/test)
==2044==
foo0: 10
   112233
   0
   0
   0
   0
   0
   0
   0
   0
   0
==2044==
==2044== HEAP SUMMARY:
==2044==     in use at exit: 40 bytes in 1 blocks
==2044==   total heap usage: 6 allocs, 6 frees, 383 bytes allocated
==2044==
==2044== LEAK SUMMARY:
==2044==    definitely lost: 40 bytes in 1 blocks
==2044==    indirectly lost: 0 bytes in 0 blocks
==2044==      possibly lost: 0 bytes in 0 blocks
==2044==    still reachable: 0 bytes in 0 blocks
==2044==         suppressed: 0 bytes in 0 blocks
==2044== Rerun with --leak-check=full to see details of leaked memory
==2044==
==2044== For counts of detected and suppressed errors, rerun with: -v
==2044== ERROR SUMMARY: 6 errors from 3 contexts (suppressed: 0 from 0)


Verify updated sssd and libsss_nss_idmap fixes the leaks. 

Update to sssd-1.16.0-19.el7_5.5.x86_64 and  libsss_nss_idmap-1.16.0-19.el7_5.5.x86_64

Run the valgrind progam again. and no leaks should be shown.


[root@host-8-242-110 opt]# valgrind ./test foo0
==3819== Memcheck, a memory error detector
==3819== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==3819== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==3819== Command: ./test foo0
==3819==
foo0: sss_nss_getgrouplist_ex 34: Numerical result out of range
==3819==
==3819== HEAP SUMMARY:
==3819==     in use at exit: 0 bytes in 0 blocks
==3819==   total heap usage: 6 allocs, 6 frees, 463 bytes allocated
==3819==
==3819== All heap blocks were freed -- no leaks are possible
==3819==
==3819== For counts of detected and suppressed errors, rerun with: -v
==3819== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

Comment 17 Sudhir Menon 2018-06-13 05:52:37 EDT

Here are the observations.

1. Able to observe the errors with sssd-1.16.0-19.el7.x86_64 and ipa-server-4.5.4-10.el7.x86_64

[root@master ~]# sss_cache -E
No cache object matched the specified search

[root@master ~]# valgrind ./test ipauser1
==16598== Memcheck, a memory error detector
==16598== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==16598== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==16598== Command: ./test ipauser1
==16598== 
==16598== Invalid read of size 8
==16598==    at 0x4C2E060: memcpy@@GLIBC_2.14 (vg_replace_strmem.c:1022)
==16598==    by 0x4E38E61: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598==  Address 0x582d090 is 0 bytes inside a block of size 40 free'd
==16598==    at 0x4C2BB58: realloc (vg_replace_malloc.c:785)
==16598==    by 0x4E3899A: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x4E38E1C: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598==  Block was alloc'd at
==16598==    at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==16598==    by 0x4E38DE4: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598== 
==16598== Invalid read of size 8
==16598==    at 0x4C2E06E: memcpy@@GLIBC_2.14 (vg_replace_strmem.c:1022)
==16598==    by 0x4E38E61: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598==  Address 0x582d0a0 is 16 bytes inside a block of size 40 free'd
==16598==    at 0x4C2BB58: realloc (vg_replace_malloc.c:785)
==16598==    by 0x4E3899A: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x4E38E1C: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598==  Block was alloc'd at
==16598==    at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==16598==    by 0x4E38DE4: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598== 
==16598== Invalid free() / delete / delete[] / realloc()
==16598==    at 0x4C2ACBD: free (vg_replace_malloc.c:530)
==16598==    by 0x4E38E6E: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598==  Address 0x582d090 is 0 bytes inside a block of size 40 free'd
==16598==    at 0x4C2BB58: realloc (vg_replace_malloc.c:785)
==16598==    by 0x4E3899A: ??? (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x4E38E1C: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598==  Block was alloc'd at
==16598==    at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==16598==    by 0x4E38DE4: sss_nss_getgrouplist_timeout (in /usr/lib64/libsss_nss_idmap.so.0.4.0)
==16598==    by 0x400671: main (in /root/test)
==16598== 
ipauser1: sss_nss_getgrouplist_ex 34: Numerical result out of range
==16598== 
==16598== HEAP SUMMARY:
==16598==     in use at exit: 56 bytes in 1 blocks
==16598==   total heap usage: 7 allocs, 7 frees, 308 bytes allocated
==16598== 
==16598== LEAK SUMMARY:
==16598==    definitely lost: 56 bytes in 1 blocks
==16598==    indirectly lost: 0 bytes in 0 blocks
==16598==      possibly lost: 0 bytes in 0 blocks
==16598==    still reachable: 0 bytes in 0 blocks
==16598==         suppressed: 0 bytes in 0 blocks
==16598== Rerun with --leak-check=full to see details of leaked memory
==16598== 
==16598== For counts of detected and suppressed errors, rerun with: -v
==16598== ERROR SUMMARY: 6 errors from 3 contexts (suppressed: 0 from 0)

2. With latest version of sssd the fix is seen.

[root@master ~]# cat /etc/redhat-release 
Red Hat Enterprise Linux Server release 7.5 (Maipo)
[root@master ~]# rpm -q ipa-server sssd
ipa-server-4.5.4-10.el7_5.2.x86_64
sssd-1.16.0-19.el7_5.5.x86_64

ipauser1 is a member of more than 10 local ipa groups
[root@master ~]# id ipauser1
uid=687800001(ipauser1) gid=687800001(ipauser1) groups=687800001(ipauser1),687800004(group3),687800003(group2),687800005(group4),687800007(group1),687800009(group7),687800006(group5),687800008(group6),687800011(group9),687800012(group10),687800002(editors),687800010(group8),687800013(group11)

[root@master ~]# valgrind ./test ipauser1
==16657== Memcheck, a memory error detector
==16657== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==16657== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==16657== Command: ./test ipauser1
==16657== 
ipauser1: sss_nss_getgrouplist_ex 34: Numerical result out of range
==16657== 
==16657== HEAP SUMMARY:
==16657==     in use at exit: 0 bytes in 0 blocks
==16657==   total heap usage: 6 allocs, 6 frees, 411 bytes allocated
==16657== 
==16657== All heap blocks were freed -- no leaks are possible
==16657== 
==16657== For counts of detected and suppressed errors, rerun with: -v
==16657== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

Comment 19 errata-xmlrpc 2018-06-26 12:49:19 EDT

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2018:1986

Note You need to log in before you can comment on or make changes to this bug.

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