RHSA-2010:0631 - Security Advisory

Topic

Updated kernel-rt packages that fix multiple security issues and several
bugs are now available for Red Hat Enterprise MRG 1.2.

The Red Hat Security Response Team has rated this update as having
important security impact. Common Vulnerability Scoring System (CVSS) base
scores, which give detailed severity ratings, are available for each
vulnerability from the CVE links in the References section.

[Updated 18 August 2010]
The CVE-2010-2240 description has been updated to reflect that the issue
affects both 32-bit and 64-bit systems. No changes have been made to the
packages.

Description

These packages contain the Linux kernel, the core of any Linux operating
system.

Security fixes:

• unsafe sprintf() use in the Bluetooth implementation. Creating a large

number of Bluetooth L2CAP, SCO, or RFCOMM sockets could result in arbitrary
memory pages being overwritten, allowing a local, unprivileged user to
cause a denial of service or escalate their privileges. (CVE-2010-1084,
Important)

• a flaw in the Unidirectional Lightweight Encapsulation implementation,

allowing a remote attacker to send a specially-crafted ISO MPEG-2 Transport
Stream frame to a target system, resulting in a denial of service.
(CVE-2010-1086, Important)

• NULL pointer dereference in nfs_wb_page_cancel(), allowing a local user

on a system that has an NFS-mounted file system to cause a denial of
service or escalate their privileges on that system. (CVE-2010-1087,
Important)

• flaw in sctp_process_unk_param(), allowing a remote attacker to send a

specially-crafted SCTP packet to an SCTP listening port on a target system,
causing a denial of service. (CVE-2010-1173, Important)

• race condition between finding a keyring by name and destroying a freed

keyring in the key management facility, allowing a local, unprivileged
user to cause a denial of service or escalate their privileges.
(CVE-2010-1437, Important)

• systems using the kernel NFS server to export a shared memory file system

and that have the sysctl overcommit_memory variable set to never overcommit
(a value of 2; by default, it is set to 0), may experience a NULL pointer
dereference, allowing a local, unprivileged user to cause a denial of
service or escalate their privileges. (CVE-2008-7256, CVE-2010-1643,
Important)

• when an application has a stack overflow, the stack could silently

overwrite another memory mapped area instead of a segmentation fault
occurring, which could cause an application to execute arbitrary code.
(CVE-2010-2240, Important)

• flaw in CIFSSMBWrite() could allow a remote attacker to send a

specially-crafted SMB response packet to a target CIFS client, resulting in
a denial of service. (CVE-2010-2248, Important)

• buffer overflow flaws in the kernel's implementation of the server-side

XDR for NFSv4 could allow an attacker on the local network to send a
specially-crafted large compound request to the NFSv4 server, possibly
resulting in a denial of service or code execution. (CVE-2010-2521,
Important)

• NULL pointer dereference in the firewire-ohci driver used for OHCI

compliant IEEE 1394 controllers could allow a local, unprivileged user with
access to /dev/fw* files to issue certain IOCTL calls, causing a denial of
service or privilege escalation. The FireWire modules are blacklisted by
default. If enabled, only root has access to the files noted above by
default. (CVE-2009-4138, Moderate)

• flaw in the link_path_walk() function. Using the file descriptor

returned by open() with the O_NOFOLLOW flag on a subordinate NFS-mounted
file system, could result in a NULL pointer dereference, causing a denial
of service or privilege escalation. (CVE-2010-1088, Moderate)

• memory leak in release_one_tty() could allow a local, unprivileged user

to cause a denial of service. (CVE-2010-1162, Moderate)

• information leak in the USB implementation. Certain USB errors could

result in an uninitialized kernel buffer being sent to user-space. An
attacker with physical access to a target system could use this flaw to
cause an information leak. (CVE-2010-1083, Low)

Red Hat would like to thank Neil Brown for reporting CVE-2010-1084; Ang Way
Chuang for reporting CVE-2010-1086; Jukka Taimisto and Olli Jarva of
Codenomicon Ltd, Nokia Siemens Networks, and Wind River on behalf of their
customer, for responsibly reporting CVE-2010-1173; the X.Org security team
for reporting CVE-2010-2240, with upstream acknowledging Rafal Wojtczuk as
the original reporter; and Marcus Meissner for reporting CVE-2010-1083.

Solution

Users should upgrade to these updated packages, which contain
backported patches to correct these issues and fix the bugs noted in
the Kernel Security Update document, linked to in the References. The
system must be rebooted for this update to take effect.

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

To install kernel packages manually, use "rpm -ivh [package]". Do not
use "rpm -Uvh" as that will remove the running kernel binaries from
your system. You may use "rpm -e" to remove old kernels after
determining that the new kernel functions properly on your system.

Affected Products

• MRG Realtime 1 x86_64
• MRG Realtime 1 i386

Fixes

• BZ - 547236 - CVE-2009-4138 kernel: firewire: ohci: handle receive packets with a data length of zero
• BZ - 555671 - MRG -146/-147 kernels have older broadcom drivers compared with RHEL5.4
• BZ - 562075 - kernel: vfs: add MNT_NOFOLLOW flag to umount(2) [mrg-1]
• BZ - 566624 - CVE-2010-1083 kernel: information leak via userspace USB interface
• BZ - 567184 - CVE-2010-1087 kernel: NFS: Fix an Oops when truncating a file
• BZ - 567813 - CVE-2010-1088 kernel: fix LOOKUP_FOLLOW on automount "symlinks"
• BZ - 569237 - CVE-2010-1086 kernel: dvb-core: DoS bug in ULE decapsulation code
• BZ - 576018 - CVE-2010-1084 kernel: bluetooth: potential bad memory access with sysfs files
• BZ - 582076 - CVE-2010-1162 kernel: tty: release_one_tty() forgets to put pids
• BZ - 584645 - CVE-2010-1173 kernel: sctp: crash due to malformed SCTPChunkInit packet
• BZ - 585094 - CVE-2010-1437 kernel: keyrings: find_keyring_by_name() can gain the freed keyring
• BZ - 594630 - kernel: security: testing the wrong variable in create_by_name() [mrg-1]
• BZ - 595970 - CVE-2008-7256 CVE-2010-1643 kernel: nfsd: fix vm overcommit crash
• BZ - 601210 - Fusion MPT misc device (ioctl) driver too verbose in message/fusion/mptctl.c::mptctl_ioctl()
• BZ - 606611 - CVE-2010-2240 kernel: mm: keep a guard page below a grow-down stack segment
• BZ - 608583 - CVE-2010-2248 kernel: cifs: Fix a kernel BUG with remote OS/2 server
• BZ - 612028 - CVE-2010-2521 kernel: nfsd4: bug in read_buf

CVEs

• CVE-2010-1437
• CVE-2010-1173
• CVE-2010-1086
• CVE-2010-1083
• CVE-2010-1162
• CVE-2010-1643
• CVE-2008-7256
• CVE-2010-2240
• CVE-2010-1084
• CVE-2010-2521
• CVE-2010-2248
• CVE-2010-1087
• CVE-2010-1088
• CVE-2009-4138

References

• http://www.redhat.com/security/updates/classification/#important
• http://www.redhat.com/docs/en-US/errata/RHSA-2010-0631/Kernel_Security_Update/index.html
• https://access.redhat.com/kb/docs/DOC-31052