RHBA-2016:2861 - Bug Fix Advisory

Topic

Updated glibc packages that fix several bugs are now available for Red Hat
Enterprise Linux 7.

Description

The glibc packages provide the standard C libraries (libc), POSIX thread
libraries (libpthread), standard math libraries (libm), and the Name Server
Caching Daemon (nscd) used by multiple programs on the system. Without these libraries, the Linux system cannot function correctly.

This update fixes the following bugs:

• Previously, Name Service Switch (NSS) module using hash-indexed files (nss_db) initialized itself incorrectly. Consequently, when nss_db module was enabled and any of the get*ent functions, such as getservent(), was called before a corresponding set*ent call, the application that called get*ent terminated unexpectedly. With this update, nss_db initialization sequence is fixed. As a result, calling get*ent functions without first calling set*ent works as expected, and the application no longer crashes. (BZ#1388635)
• The nss_db module failed to request larger result buffers when parsing group entries. As a consequence, group entries with a size in a specific range were skipped. With this update, nss_db detects when a group list does not fit into the result buffer and requests a larger buffer. As a result, group entries in the affected size range are processed correctly. (BZ#1388637)
• Previously, installing an Identity Management (IdM) server or client did not add the "sss" option to the "initgroups" lookup entry in the /etc/nsswitch.conf file. As a consequence, looking up secondary groups for users managed by the System Security Services Daemon (SSSD) did not work as expected. With the update, looking up secondary groups works correctly. (BZ#1388638)
• Previously, the nss_db module did not properly handle a protocol mismatch during lookups in the service database. As a consequence, lookups in the service database could enter an infinite loop. Now, nss_db deals with protocol mismatches and proceeds with the next entry. As a result, service entries are found as expected without entering an infinite loop. (BZ#1388639)

Users of glibc are advised to upgrade to these updated packages, which fix these bugs.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.3 x86_64
• Red Hat Enterprise Linux Server - AUS 7.7 x86_64
• Red Hat Enterprise Linux Server - AUS 7.6 x86_64
• Red Hat Enterprise Linux Server - AUS 7.4 x86_64
• Red Hat Enterprise Linux Server - AUS 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 7 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.4 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.3 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.5 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.4 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.3 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.5 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.4 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.3 ppc64le
• Red Hat Enterprise Linux Server - TUS 7.7 x86_64
• Red Hat Enterprise Linux Server - TUS 7.6 x86_64
• Red Hat Enterprise Linux Server - TUS 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x
• Red Hat Enterprise Linux EUS Compute Node 7.7 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.6 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.5 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.4 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.3 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.7 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.6 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.4 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.3 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le

Fixes

• BZ - 1388635 - glibc: nss_db: get*ent crashes without preceding set*ent
• BZ - 1388637 - glibc: nss_db: long group entries are skipped
• BZ - 1388638 - glibc: default nsswitch.conf should not set initgroups
• BZ - 1388639 - glibc: nss_db: Endless loop in services database processing

CVEs

(none)

References

(none)