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Security update for Linux kernel (k_deflt)

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(Last modified: 05MAY2003)


solutions Security update for Linux kernel (k_deflt) SuSE Linux Maintenance Web (118d4fc1eb5934a1301315bedd67f004)

Applies to

Product(s): SuSE Linux Enterprise Server 7 for IBM zSeries

Package: k_deflt
Release: 20030505
Obsoletes: none

Indications

This update should be installed on all systems for security reasons.
This article applies to systems with the k_deflt kernel package installed, please use the appropriate kernel package if you are using a different kernel:
You can find out which kernel package you are using with
rpm -qf /boot/kernel/image

Contraindications

Using z/VM 4.3 and PTF UM30652 not installed.

Description

This update fixes a security vulnerability in the Linux kernel (CAN-2003-0127) and contains fixes for high SMP workloads and ERP scenarios. The changes in detail are:
Security fix
The vulnerability allows a local unprivileged attacker to
gain root privileges by using ptrace/strace in
combination with automatic kernel module loading on request, also known
as "kmod".
As a temporary workaround, it is possible to disable the automatic loading of kernel modules by running the following command as user "root":
echo /no/such/file >/proc/sys/kernel/modprobe
This patch also includes improved argument checking for getting and setting the IEEE instruction pointer of the last floating point exception in the S/390 specific code to prevent possible crashes if it is wrongly used.
Restrictions for path-grouped DASDs
  • Do not re-configure or re-cable path-grouped DASDs or path-grouped channel-attached tapes while the system is running, to avoid problems with path re-validation code.
  • In such configuration the system may hang during re-boot. As a safe workaround use the "halt" command and perform an IPL CLEAR.
S/390 specific fixes
  • Fix crashes in user access if the CPU already called schedule.
  • Fix skipping of more than 511 blocks in the tape driver.
  • Fix handling of memory allocation failures.
  • Fix handling of user access return status with ptrace().
  • Fix codepage conversion with strings longer than 256 bytes.
  • Fix interrupt handling related to status pending condition.
  • Fix path not operational detection using last path used mask.
  • Fix lost interrupt because of zero basic sense data.
  • Fix deadlock with all CPUs in enable_cpu_sync_isc.
  • Fix oops during dynamic addition of an FCP adapter..
  • Fix TLB handling for high SMP workloads with heaps of threads.
  • Fix possible user process crash or kernel oops because of 31-bit address space overflow.
  • Fix too much logging for incoming ELS via printk().
  • Fix ESS DASD support: Enhanced and fixed various ERP scenarios.
  • Disable CONFIG_WATCHDOG_NOWAYOUT by default.
  • Add info for DASD and QDIO into kerntypes.c.
General fixes
  • Fix a longstanding TCP problem that can lead to hanging ssh sessions.
  • fix SMP races with hanging rsync processes and data loss on power failure.
  • Fix possible data exposure and data corruption caused by abusing O_DIRECT.
  • Prevent statfs overflow for huge NFS filesystems.
  • Fix problem in O_DIRECT implementation when reading files with holes in it.
  • Fix possible oops when trying to free pages in async I/O.
  • Fix longstanding off-by-one error in keventd initialization that can lead to system freeze.
New drivers and driver updates
  • Backport of tape driver from 2.4.19.
  • Backport of crypto device driver from 2.4.19.
  • Add Software Watchdog module.
  • Add 3590 tape support.
IBM code drops
This update includes the following IBM code drops:
  • 2003-02-20 kernel 2.4.17 for the "August 2001 stream"

Installation notes

This update is provided as an RPM package that can easily be installed onto a running system by using these commands:
rpm -Fvh k_deflt.rpm zipl
please do not forget to run zipl after installing the k_deflt for the system to remain bootable.
Finally, reboot the system with
shutdown -r now
to load the new kernel (replace "now" with the appropriate amount of time to allow local users to cleanly log out, for example "+5" for five minutes.)

links to download packages

Download Source Packages

Download the source code of the patches for maintained products.


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