RHBA-2015:0317 - Bug Fix Advisory

Topic

Updated bash packages that fix several bugs and add various enhancements are now
available for Red Hat Enterprise Linux 7.

Description

The bash packages provide the Bash (Bourne-again shell) shell, which is the
default shell for Red Hat Enterprise Linux.

The bash packages have been upgraded to upstream version 4.2.46, with patches
equivalent to upstream patch levels 47-49, 52 and 53 also applied, which
provides a number of bug fixes and enhancements over the previous version.
(BZ#1073683)

This update also fixes the following bugs:

• After editing a command in vi visual mode, Bash echoed every substituted

command, which produced a lengthy shell output when editing loops. This behavior
has been changed and Bash now only echoes the original string in the described
scenario. (BZ#1102813)

• The bash(1) manual page did not mention that 512-byte blocks are used for the

"-c" and "-f" options in POSIX mode. This update adds the missing piece of
information to bash(1). (BZ#1112709)

• If a command substitution enclosed in double-quote characters contained a

double-quoted string, Bash performed brace expansion on the command before
performing command substitution. Consequently, the command created different
output than expected. The bug has been fixed, and command substitution now
precedes brace expansion in the described case. (BZ#1116301)

• The previous version of the bash(1) manual page did not provide a clear

description of the "break", "continue", and "suspend" built-in commands. This
update corrects this error, and extpands the manual page to provide accurate and
complete descriptions of these commands. (BZ#1126370)

• When the HISTFILESIZE variable was set to a value larger than zero, the

HISTSIZE variable was set to zero as well. If the .bash_history file had time
stamps enabled and was not empty, executing the "su - " command caused Bash to
become unresponsive. This bug has been fixed, and Bash no longer hangs in the
aforementioned scenario. (BZ#1126396)

• The bash(1) manual page did not reflect the behavior changes in the "extglob"

option introduced in Bash version 4.1. This update adds a correct description of
"extglob" behavior to the bash(1) man page. (BZ#1126401)

• When Bash parsed a function definition that contained a here-document

delimited by end-of-file (or end-of-string), it left the closing delimiter
uninitialized. This could cause an invalid memory access when the parsed
function was later copied. This bug has been fixed and the closing delimiter
is now initialized properly.

• A combination of nested command substitutions and function importing from

the environment could cause bash to execute code that appeared in the
environment variable value following the function definition. This bug has been
fixed and the aforementioned problem no longer occurs. (BZ#1175647)

Users of bash are advised to upgrade to these updated packages, which fix these
bugs and add these enhancements.

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 Server from RHUI 7 x86_64
• 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 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

Fixes

• BZ - 1073683 - Array slicing broken
• BZ - 1116301 - Bash performs brace expansion on commands with double-quoted strings within a double-quoted command-substitution

CVEs

(none)

References

(none)