Date: Tue, 17 Apr 2001 14:31:46 -0600
From: Linux Mandrake Security Team <security@LINUX-MANDRAKE.COM>
Subject: MDKSA-2001:037 - kernel update
Linux-Mandrake Security Update Advisory
Package name: kernel
Date: April 17th, 2001
Advisory ID: MDKSA-2001:037
Affected versions: 6.0, 6.1, 7.0, 7.1, 7.2, Corporate Server 1.0.1
Problem Description:
A number of security problems have been found in the Linux
kernels prior to the latest 2.2.19 kernel. Following is a list of
problems based on the 2.2.19 release notes as found on http://www.linux.org.uk/
binfmt_misc used user pages directly
the CPIA driver had an off-by-one error in the buffer code
which made it possible for users to write into kernel memory
the CPUID and MSR drivers had a problem in the module unloading
code which could cause a system a crash if they were set to
automatically load and unload
there was a possible hang in the classifier code
the getsockopt and setsockopt system calls did not handle sign
bits correctly which made a local DoS and other attacks
possible
the sysctl system call did not handle sign bits correctly which
allowed a user to write in kernel memory
ptrace/exec races that could give a local user extra
privileges
possible abuse of a boundary case in the sockfilter code
SYSV shared memory code could overwrite recently freed memory
which might cause problems
the packet lengh checks in the masquerading code were a bit lax
(probably not exploitable)
some x86 assembly bugs caused the wrong number of bytes to be
copied
a local user could deadlock the kernel due to bugs in the UDP
port allocation.
All of these problems are corrected in the 2.2.19 kernel and it
is highly recommended that all Linux-Mandrake users upgrade their
systems to this kernel.
It is also recommended that you download the necessary RPMs and
upgrade manually by following these steps:
Replace the kernel revision noted in the above instructions with
those from the packages you downloaded. You will then be able to
reboot and use the new kernel and remove the older kernel when you
are comfortable using the upgraded one.
Please verify the update prior to upgrading to ensure the
integrity of the downloaded package. You can do this with the
command: rpm --checksig package.rpm
You can get the GPG public key of the Linux-Mandrake Security Team
at http://www.linux-mandrake.com/en/security/RPM-GPG-KEYS
If you use MandrakeUpdate, the verification of md5 checksum and GPG
signature is performed automatically for you.
Updated packages are available in the "updates/[ver]/RPMS/"
directory. For example, if you are looking for an updated RPM
package for Linux-Mandrake 7.2, look for it in "updates/7.2/RPMS/".
Updated source RPMs are available as well, but you generally do not
need to download them.
Please be aware that sometimes it takes the mirrors a few hours
to update.
You can view other security advisories for Linux-Mandrake
at:
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open to anyone to discuss Linux-Mandrake security specifically and
Linux security in general.
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