RHBA-2011:0225 - Bug Fix Advisory

Topic

An updated sysklogd package that fixes multiple bugs is now available for Red
Hat Enterprise Linux 4.

Description

The sysklogd package contains two system utilities (syslogd and klogd) that
provide support for system logging. Syslogd and klogd run as daemons and log
system messages such as sendmail logs, security logs, and error logs to various
places.

This update fixes the following bugs:

• Previously, syslogd called ctime() which locked a fast userspace mutex (futex)

when a message was logged. If at the same moment also a MARK message alarm
occured then the ctime() was called from the signal handler and the futex was
not released. With this update, syslogd does no longer generate any input/output
nor does it call ctime() in the signal handler. (BZ#491637)

• Previously, the syslog daemon could receive the signal "SIGALRM" when users

ran the writev() function. Due to this behavior, syslogd stopped to write
messages to /dev/console. This update reschedules the ALARM just prior to call
writev(). Now, syslogd continues to write messages to /dev/console. (BZ#500354)

• Previously, the errno value of "select" was checked after the "Mark" message

logging functions reset this value from EINTR to EINVAL. Due to this behavior,
the -m option with nonzero arguments resulted in incorrect 'select: Invalid
argument' messages in the log. This update stores the errno value from "select"
to the new variable. No more incorrect error messages are logged. (BZ#625795)

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

Solution

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

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 4 x86_64
• Red Hat Enterprise Linux Server 4 ia64
• Red Hat Enterprise Linux Server 4 i386
• Red Hat Enterprise Linux Workstation 4 x86_64
• Red Hat Enterprise Linux Workstation 4 ia64
• Red Hat Enterprise Linux Workstation 4 i386
• Red Hat Enterprise Linux Desktop 4 x86_64
• Red Hat Enterprise Linux Desktop 4 i386
• Red Hat Enterprise Linux for IBM z Systems 4 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390
• Red Hat Enterprise Linux for Power, big endian 4 ppc

Fixes

• BZ - 491637 - possible deadlock in ctime() called from signal handler
• BZ - 500354 - syslogd stops writing any messages to /dev/console after an EINTR in syscall
• BZ - 625795 - Using -m option results in 'select: Invalid argument' messages in the log

CVEs

(none)

References

(none)