Synopsis

Important: kernel security and bug fix update

Type/Severity

Security Advisory: Important

Topic

Updated kernel packages that fix multiple security issues and several bugs
are now available for Red Hat Enterprise Linux 5.

This update has been rated as having important security impact by the Red
Hat Security Response Team.

Description

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

Security fixes:

• an array index error was found in the gdth driver. A local user could

send a specially-crafted IOCTL request that would cause a denial of service
or, possibly, privilege escalation. (CVE-2009-3080, Important)

• a flaw was found in the FUSE implementation. When a system is low on

memory, fuse_put_request() could dereference an invalid pointer, possibly
leading to a local denial of service or privilege escalation.
(CVE-2009-4021, Important)

• Tavis Ormandy discovered a deficiency in the fasync_helper()

implementation. This could allow a local, unprivileged user to leverage a
use-after-free of locked, asynchronous file descriptors to cause a denial
of service or privilege escalation. (CVE-2009-4141, Important)

• the Parallels Virtuozzo Containers team reported the RHSA-2009:1243

update introduced two flaws in the routing implementation. If an attacker
was able to cause a large enough number of collisions in the routing hash
table (via specially-crafted packets) for the emergency route flush to
trigger, a deadlock could occur. Secondly, if the kernel routing cache was
disabled, an uninitialized pointer would be left behind after a route
lookup, leading to a kernel panic. (CVE-2009-4272, Important)

• the RHSA-2009:0225 update introduced a rewrite attack flaw in the

do_coredump() function. A local attacker able to guess the file name a
process is going to dump its core to, prior to the process crashing, could
use this flaw to append data to the dumped core file. This issue only
affects systems that have "/proc/sys/fs/suid_dumpable" set to 2 (the
default value is 0). (CVE-2006-6304, Moderate)

The fix for CVE-2006-6304 changes the expected behavior: With suid_dumpable
set to 2, the core file will not be recorded if the file already exists.
For example, core files will not be overwritten on subsequent crashes of
processes whose core files map to the same name.

• an information leak was found in the Linux kernel. On AMD64 systems,

32-bit processes could access and read certain 64-bit registers by
temporarily switching themselves to 64-bit mode. (CVE-2009-2910, Moderate)

• the RHBA-2008:0314 update introduced N_Port ID Virtualization (NPIV)

support in the qla2xxx driver, resulting in two new sysfs pseudo files,
"/sys/class/scsi_host/[a qla2xxx host]/vport_create" and "vport_delete".
These two files were world-writable by default, allowing a local user to
change SCSI host attributes. This flaw only affects systems using the
qla2xxx driver and NPIV capable hardware. (CVE-2009-3556, Moderate)

• permission issues were found in the megaraid_sas driver. The "dbg_lvl"

and "poll_mode_io" files on the sysfs file system ("/sys/") had
world-writable permissions. This could allow local, unprivileged users to
change the behavior of the driver. (CVE-2009-3889, CVE-2009-3939, Moderate)

• a NULL pointer dereference flaw was found in the firewire-ohci driver

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

• a buffer overflow flaw was found in the hfs_bnode_read() function in the

HFS file system implementation. This could lead to a denial of service if a
user browsed a specially-crafted HFS file system, for example, by running
"ls". (CVE-2009-4020, Low)

Bug fix documentation for this update will be available shortly from
www.redhat.com/docs/en-US/errata/RHSA-2010-0046/Kernel_Security_Update/
index.html

Users should upgrade to these updated packages, which contain backported
patches to correct these issues. The system must be rebooted for this
update to take effect.

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/docs/DOC-11259

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 for x86_64 - Extended Update Support 5.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 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 IBM z Systems - Extended Update Support 5.4 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.4 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 526068 - CVE-2009-3889 CVE-2009-3939 kernel: megaraid_sas permissions in sysfs
• BZ - 526788 - CVE-2009-2910 kernel: x86_64 32 bit process register leak
• BZ - 537027 - Timedrift on VM with pv_clock enabled, causing system hangs and sporadic time behaviour [rhel-5.4.z]
• BZ - 537177 - CVE-2009-3556 kernel: qla2xxx NPIV vport management pseudofiles are world writable
• BZ - 537273 - CVE-2006-6304 kernel: use flag in do_coredump()
• BZ - 538734 - CVE-2009-4021 kernel: fuse: prevent fuse_put_request on invalid pointer
• BZ - 539414 - CVE-2009-3080 kernel: gdth: Prevent negative offsets in ioctl
• BZ - 539686 - bnx2: panic in bnx2_poll_work() [rhel-5.4.z]
• BZ - 540736 - CVE-2009-4020 kernel: hfs buffer overflow
• BZ - 540896 - PV clock fix throws off database application time [rhel-5.4.z]
• BZ - 542582 - kdump corefile cannot be backtraced in IA64 [rhel-5.4.z]
• BZ - 543448 - Using IPoIB, losing connectivity with 1 host, other hosts accessible [rhel-5.4.z]
• BZ - 544978 - glock_workqueue -- glock ref count via gfs2_glock_hold [rhel-5.4.z]
• BZ - 545411 - CVE-2009-4272 kernel: emergency route cache flushing leads to node deadlock
• BZ - 547236 - CVE-2009-4138 kernel: firewire: ohci: handle receive packets with a data length of zero
• BZ - 547521 - CRM#1971672, Data loss in GFS2 when multiple nodes writes to same file [rhel-5.4.z]
• BZ - 547530 - kernel: BUG: soft lockup - CPU#1 stuck for 13s! [httpd:4490] [rhel-5.4.z]
• BZ - 547906 - CVE-2009-4141 kernel: create_elf_tables can leave urandom in a bad state
• BZ - 548370 - kernel: sleeping vfs_check_frozen in called in atomic context from do_wp_page [rhel-5.4.z]
• BZ - 549905 - hvm, x86_64 guest panic on 2.6.18-164.9.1.el5 [rhel-5.4.z]
• BZ - 549906 - [NetApp 5.4.z bug] Emulex FC ports on RHEL 5.4 GA offlined during target controller faults [rhel-5.4.z]
• BZ - 549907 - Hang when echoing to /proc/sys/net/ipv4/route/secret_interval [rhel-5.4.z]
• BZ - 549908 - resize2fs online resize hangs [rhel-5.4.z]
• BZ - 550968 - RHEL5.4 guest with PV clock: inconsistent times returned by clock_gettime(CLOCK_REALTIME) and gettimeofday() [rhel-5.4.z]

CVEs

• CVE-2009-2910
• CVE-2009-3939
• CVE-2009-3889
• CVE-2009-4138
• CVE-2009-4272
• CVE-2009-3080
• CVE-2009-4141
• CVE-2009-3556
• CVE-2009-4020
• CVE-2009-4021
• CVE-2006-6304

References