RHBA-2009:0060 - Bug Fix Advisory

Topic

An updated tcsh package that fixes various bugs is now available.

Description

Tcsh is an enhanced and compatible version of the C shell (csh). Tcsh is a
command language interpreter, which can be used as an interactive login
shell, as well as a shell script command processor.

This updated tcsh package includes fixes for the following bugs:

• the default Red Hat Enterprise Linux 5 kernel runs with the

"kernel.randomize_va_space" sysctl turned on, which randomizes the system's
address space. Because tcsh used its own custom, internal implementation of
the malloc() function which did not handle address space randomization
well, applications run from the tcsh shell would occasionally crash due to
a segmentation fault. In this updated package, tcsh has been changed to use
the system malloc() function, thus resolving this issue.

• tcsh scripts broke when using case statements that contained the "end"

keyword. Running a tcsh script that contained the "end" keyword produced
the following output when the "end" statement was reached:

end: Not in while/foreach.

In this updated package, "end" keywords no longer break scripts.

• strings of numbers which began with the number "0", and which should have

been interpreted as octal numbers by tcsh, were instead being interpreted
as decimal numbers. In this updated package, tcsh correctly considers
strings of digits starting with zero to be octal numbers.

• in the following construction, tcsh did not check whether both variables,

sel1 and sel2, were in range when selecting only part of multi
word-variable--it only checked sel2:

$name[sel1-sel2]

In this updated package, both parts of a selector in this kind of
construction are checked, thus resolving the issue.

• due to a pointer position miscalculation error, tcsh would sometimes

"garble" multi-byte characters in certain such situations, such as within
here-documents. In this updated package, tcsh no longer corrupts multi-byte
characters, resolving the issue.

• the previous tcsh man page stated that memory limits could be set using

the "memoryuse" option. However, this option was not honored by tcsh, and
memory limits were never applied. It is not possible to limit memory usage
using either the "memoryuse" or the "RLIMIT_RSS" option. The tcsh man page
has been updated to reflect this.

• the previous tcsh(1) man page did not state distinctly that, when

multiple operators with the same precedence level are used within a single
expression, the operators are are then evaluated from right-to-left,
starting with the rightmost one. The tcsh(1) man page is now clearer about
this point.

• the description of the second form of the shell built-in "set" command

was given twice in the tcsh man page. The redundant description has been
removed in this updated package.

All users of tcsh are advised to upgrade to this updated package, which
resolves these issues.

Solution

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

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/FAQ_58_10188

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 430459 - A description of builtin "set" is redundant
• BZ - 435398 - $name[selector]:it should fail when any number of 'selector' is out of range
• BZ - 436956 - [BUG] CRM# 1478864 - tcsh scripts with case statements having end keyword breaks oddly.
• BZ - 438109 - strings which begin with '0' are not recognized as octal numbers
• BZ - 442536 - [5.3] Manpage change clarifying the calculation order of operator '%', '/' and '*' in tcsh.

CVEs

(none)

References

(none)