Linux kernel 2.6.x, when using both NFS and EXT3, allows remote attackers to cause a denial of service (file system panic) via a crafted UDP packet with a V2 lookup procedure that specifies a bad file handle (inode number), which triggers an error and causes an exported directory to be remounted read-only.

Updated kernel packages that fix security issues are now available. 

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

The Linux kernel handles the basic functions of the operating system. 

These new kernel packages contain fixes for the security issues described below :


From Red Hat Security Advisory 2006-0617 :

* a flaw in the proc file system that allowed a local user to use a suid-wrapper for scripts to gain root privileges (CVE-2006-3626, Important)

* a flaw in the SCTP implementation that allowed a local user to cause a denial of service (panic) or to possibly gain root privileges (CVE-2006-3745, Important)

* a flaw in NFS exported ext2/ext3 partitions when handling invalid inodes that allowed a remote authenticated user to cause a denial of service (filesystem panic) (CVE-2006-3468, Important)

* a flaw in the restore_all code path of the 4/4GB split support of non-hugemem kernels that allowed a local user to cause a denial of service (panic) (CVE-2006-2932, Important)

* a flaw in IPv4 netfilter handling for the unlikely use of SNMP NAT processing that allowed a remote user to cause a denial of service (crash) or potential memory corruption (CVE-2006-2444, Moderate)

* a flaw in the DVD handling of the CDROM driver that could be used together with a custom built USB device to gain root privileges (CVE-2006-2935, Moderate)

* a flaw in the handling of O_DIRECT writes that allowed a local user to cause a denial of service (memory consumption) (CVE-2004-2660, Low)

* a flaw in the SCTP chunk length handling that allowed a remote user to cause a denial of service (crash) (CVE-2006-1858, Low)

* a flaw in the input handling of the ftdi_sio driver that allowed a local user to cause a denial of service (memory consumption) (CVE-2006-2936, Low)

In addition a bugfix was added to enable a clean reboot for the IBM Pizzaro machines.

Red Hat would like to thank Wei Wang of McAfee Avert Labs and Kirill Korotaev for reporting issues fixed in this erratum.


From Red Hat Security Advisory ELSA-2006-0689 :

* a flaw in the SCTP support that allowed a local user to cause a denial of service (crash) with a specific SO_LINGER value.
(CVE-2006-4535, Important)

* a flaw in the hugepage table support that allowed a local user to cause a denial of service (crash). (CVE-2005-4811, Important)

* a flaw in the mprotect system call that allowed setting write permission for a read-only attachment of shared memory.
(CVE-2006-2071, Moderate)

* a flaw in HID0[31] (en_attn) register handling on PowerPC 970 systems that allowed a local user to cause a denial of service.
(crash) (CVE-2006-4093, Moderate)

* a flaw in the perfmon support of Itanium systems that allowed a local user to cause a denial of service by consuming all file descriptors. (CVE-2006-3741, Moderate)

* a flaw in the ATM subsystem. On systems with installed ATM hardware and configured ATM support, a remote user could cause a denial of service (panic) by accessing socket buffers memory after freeing them.
(CVE-2006-4997, Moderate)

* a flaw in the DVB subsystem. On systems with installed DVB hardware and configured DVB support, a remote user could cause a denial of service (panic) by sending a ULE SNDU packet with length of 0.
(CVE-2006-4623, Low)

* an information leak in the network subsystem that possibly allowed a local user to read sensitive data from kernel memory. (CVE-2006-0039, Low)

In addition, two bugfixes for the IPW-2200 wireless driver were included. The first one ensures that wireless management applications correctly identify IPW-2200 controlled devices, while the second fix ensures that DHCP requests using the IPW-2200 operate correctly.

Red Hat would like to thank Olof Johansson, Stephane Eranian and Solar Designer for reporting issues fixed in this erratum.

This kernel update fixes the following security problems :

  - A double userspace copy in a SCTP ioctl allows local     attackers to overflow a buffer in the kernel,     potentially allowing code execution and privilege     escalation. [#199441]. (CVE-2006-3745)

  - Local attackers were able to crash PowerPC systems with     PPC970 processor using a not correctly disabled     privileged instruction ('attn'). [#197810].
    (CVE-2006-4093)

  - Remote attackers able to access an NFS of a ext2 or ext3     filesystem can cause a denial of service (file system     panic) via a crafted UDP packet with a V2 lookup     procedure that specifies a bad file handle (inode     number), which triggers an error and causes an exported     directory to be remounted read-only. [#192988].
    (CVE-2006-3468)

and the following non security bugs :

  - XEN patches/fixes :

  - kunmap_atomic() must zap the PTE to avoid dangling     references.

  - Fix oops on io scheduler unload on a process without ioc     (backport)

  - OCFS2 updated to to version 1.2.3.

  - update patches.arch/ppc-update_gtod-race.patch: restrict     to 64bit only because it leads to deadlocks on ppc32     [#202146]

  - Fix MCA recovery in context switch path [#199472]

  - fix gettimeofday vs. update_gtod race [#197699]

  - LKCD: dump all slab pages. [#196330]

  - Make idle io be lowest priority best-effort [#195387]

  - Fix dropping of wrong cic. [#195387]

  - Fix stale file handle problem with subtree_checking.
    [#195040]

  - Remove Altix PROM bit that can race on MCAs. [#193296]

  - Prevent silent data corruption caused by XPC. [#193132]

  - Fix race condition during COW [#192259]

  - sched: fix group power for allnodes_domains [#191929]

  - Allow dma_alloc_coherent() to work for regions up to     2MB. [#191615]

  - fix ABBA deadlock between cpuset callback_sem and     hotplug cpucontrol mutex [#191582]

  - Check for existing sysfs directory prior to creating one     [#191360]

  - Fix possible NFS panic in readdir. [#189951]

  - MPT driver: Fix oops on module loading [#189534]

  - SUNRPC: Ensure that rpc_mkpipe returns a refcounted     dentry [#183013]

  - Pass file mode on DMAPI remove events [#182691]

  - MPT driver: Fix oops during error recovery [#177919]

  - flush icache on POWER4 cpus to fix itrace crash     [#171699]

  - KPROBES: Fix system panic if user doing copy_from_user     in the probe handlers [#171483]

  - patches.xen/xen-balloon-max-target: Expose limit domain     can be ballooned up to [#152667]

  - Avoid possible soft-lockup, particularly related to md     [#152099]

  - reiserfs: fix transaction overflowing [#145070]

This kernel update fixes the following security problems :

  - A double userspace copy in a SCTP ioctl allows local     attackers to overflow a buffer in the kernel,     potentially allowing code execution and privilege     escalation. [#199441]. (CVE-2006-3745)

  - Local attackers were able to crash PowerPC systems with     PPC970 processor using a not correctly disabled     privileged instruction ('attn'). [#197810].
    (CVE-2006-4093)

  - Remote attackers able to access an NFS of a ext2 or ext3     filesystem can cause a denial of service (file system     panic) via a crafted UDP packet with a V2 lookup     procedure that specifies a bad file handle (inode     number), which triggers an error and causes an exported     directory to be remounted read-only. [#192988].
    (CVE-2006-3468)

and the following non security bugs :

  - XEN patches/fixes :

  - kunmap_atomic() must zap the PTE to avoid dangling     references.

  - Fix oops on io scheduler unload on a process without ioc     (backport)

  - OCFS2 updated to to version 1.2.3.

  - update patches.arch/ppc-update_gtod-race.patch: restrict     to 64bit only because it leads to deadlocks on ppc32     [#202146]

  - Fix MCA recovery in context switch path [#199472]

  - fix gettimeofday vs. update_gtod race [#197699]

  - LKCD: dump all slab pages. [#196330]

  - Make idle io be lowest priority best-effort [#195387]

  - Fix dropping of wrong cic. [#195387]

  - Fix stale file handle problem with subtree_checking.
    [#195040]

  - Remove Altix PROM bit that can race on MCAs. [#193296]

  - Prevent silent data corruption caused by XPC. [#193132]

  - Fix race condition during COW [#192259]

  - sched: fix group power for allnodes_domains [#191929]

  - Allow dma_alloc_coherent() to work for regions up to     2MB. [#191615]

  - fix ABBA deadlock between cpuset callback_sem and     hotplug cpucontrol mutex [#191582]

  - Check for existing sysfs directory prior to creating one     [#191360]

  - Fix possible NFS panic in readdir. [#189951]

  - MPT driver: Fix oops on module loading [#189534]

  - SUNRPC: Ensure that rpc_mkpipe returns a refcounted     dentry [#183013]

  - Pass file mode on DMAPI remove events [#182691]

  - MPT driver: Fix oops during error recovery [#177919]

  - flush icache on POWER4 cpus to fix itrace crash     [#171699]

  - KPROBES: Fix system panic if user doing copy_from_user     in the probe handlers [#171483]

  - patches.xen/xen-balloon-max-target: Expose limit domain     can be ballooned up to [#152667]

  - Avoid possible soft-lockup, particularly related to md     [#152099]

  - reiserfs: fix transaction overflowing [#145070]

Fixes for S/390 :

  - IBM Patchcluster 6

  - Problem-ID: 25393 - xpram: module parameter parsing.

  - Problem-ID: 23720 - zfcp: failed paths remain     unavailable

  - Problem-ID: 23989 - zfcp: ERP 'deadlock' when     registering a scsi device or remote port (partII)

  - Problem-ID: 24645 - qeth: qethconf not adding ipa     entries

  - Problem-ID: 25507 - cio: 5 min timeout after setting     chpid offline.

  - Problem-ID: 25511 - cio: Fix some path grouping and path     verification related problems.

  - IBM Patchcluster 7

  - Problem-ID: 25564 - qeth: race during setup of qeth     device

  - Problem-ID: 25799 - iucv: multiple interfaces with same     peer established

  - Problem-ID: 25801 - cio: permanent subchannel busy     conditions may cause I/O stall

  - Problem-ID: 23575 - cio: module containing ccwgroup     driver cannot be unloaded.

  - Problem-ID: 25802 - cio: Disallow ccwgroup devices     containing non-unique ccw devices.

  - Problem-ID: 26016 - qeth: race when reboot and recovery     run concurrently

  - Problem-ID: 26068 - qeth: kernel panic under heavy UDP     workload

  - Problem-ID: 26103 - cio: I/O stall due to lost interupt     after CHPID vary off/on cycle

  - Problem-ID: 26014 - qeth: stack trace with msg     'inconsistent lock state'

  - Problem-ID: 26118 - dasd: kernel BUG when setting a DASD     device offline.

  - Problem-ID: 19628 - zfcp: do adapter reopen on do_QDIO     error

  - Problem-ID: 26144 - qeth: Setrouting for ipv6 invalid on     hipersockets.

  - Problem-ID: 23427, 24855 - cio: Inconsistent values in     channel measurement facility.

  - Problem-ID: 24511 - dasd: Cleanup queue fails during     offline processing.

    For further describtion of the named Problem-IDs, please     look to     http://www-128.ibm.com/developerworks/linux/linux390/apr     il20 04_recommended.html

In the former Kernel the HZ_TIMER was switched on by default. This is now switched off. (see cat /proc/sys/kernel/hz_timer on the system)

A Denial of service vulnerability was reported in iptables' SCTP conntrack module. On computers which use this iptables module, a remote attacker could exploit this to trigger a kernel crash.
(CVE-2006-2934)

A buffer overflow has been discovered in the dvd_read_bca() function.
By inserting a specially crafted DVD, USB stick, or similar automatically mounted removable device, a local user could crash the machine or potentially even execute arbitrary code with full root privileges. (CVE-2006-2935)

The ftdi_sio driver for serial USB ports did not limit the amount of pending data to be written. A local user could exploit this to drain all available kernel memory and thus render the system unusable.
(CVE-2006-2936)

James McKenzie discovered a Denial of Service vulnerability in the NFS driver. When exporting an ext3 file system over NFS, a remote attacker could exploit this to trigger a file system panic by sending a specially crafted UDP packet. (CVE-2006-3468)

Wei Wang of McAfee Avert Labs discovered a buffer overflow in the sctp_make_abort_user() function of iptables' SCTP module. On computers which use this module, a local attacker could exploit this to execute arbitrary code with root privileges. (CVE-2006-3745)

Olof Johansson discovered that the kernel did not disable the 'HID0' bit on PowerPC 970 processors so that the ATTN instruction was enabled. A local user could exploit this to crash the kernel. This flaw only affects the powerpc architecture. (CVE-2006-4093)

The UDF file system does not handle extends larger than 1 GB, but did not check for this restriction on truncating files. A local user could exploit this to crash the kernel. (CVE-2006-4145).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

This kernel update fixes the following security problems :

  - CVE-2006-3745: A double userspace copy in a SCTP ioctl     allows local attackers to overflow a buffer in the     kernel, potentially allowing code execution and     privilege escalation. [#199441]

  - CVE-2006-4093: Local attackers were able to crash     PowerPC systems with PPC970 processor using a not     correctly disabled privileged instruction ('attn').
    [#197810]

  - CVE-2006-3468: Remote attackers able to access an NFS of     a ext2 or ext3 filesystem can cause a denial of service     (file system panic) via a crafted UDP packet with a V2     lookup procedure that specifies a bad file handle (inode     number), which triggers an error and causes an exported     directory to be remounted read-only. [#192988]

Additionaly this kernel catches up to the SLE 10 state of the kernel, with massive additional fixes.

A number of vulnerabilities were discovered and corrected in the Linux 2.6 kernel :

Prior to and including 2.6.16-rc2, when running on x86_64 systems with preemption enabled, local users can cause a DoS (oops) via multiple ptrace tasks that perform single steps (CVE-2006-1066).

Prior to 2.6.16, a directory traversal vulnerability in CIFS could allow a local user to escape chroot restrictions for an SMB-mounted filesystem via '..\' sequences (CVE-2006-1863).

Prior to 2.6.16, a directory traversal vulnerability in smbfs could allow a local user to escape chroot restrictions for an SMB-mounted filesystem via '..\' sequences (CVE-2006-1864).

Prior to to 2.6.16.23, SCTP conntrack in netfilter allows remote attackers to cause a DoS (crash) via a packet without any chunks, causing a variable to contain an invalid value that is later used to dereference a pointer (CVE-2006-2934).

The dvd_read_bca function in the DVD handling code assigns the wrong value to a length variable, which could allow local users to execute arbitrary code via a crafted USB storage device that triggers a buffer overflow (CVE-2006-2935).

Prior to 2.6.17, the ftdi_sio driver could allow local users to cause a DoS (memory consumption) by writing more data to the serial port than the hardware can handle, causing the data to be queued (CVE-2006-2936).

The 2.6 kernel, when using both NFS and EXT3, allowed remote attackers to cause a DoS (file system panic) via a crafted UDP packet with a V2 lookup procedure that specifies a bad file handle (inode number), triggering an error and causing an exported directory to be remounted read-only (CVE-2006-3468).

The 2.6 kernel's SCTP was found to cause system crashes and allow for the possibility of local privilege escalation due to a bug in the get_user_iov_size() function that doesn't properly handle overflow when calculating the length of iovec (CVE-2006-3745).

The provided packages are patched to fix these vulnerabilities. All users are encouraged to upgrade to these updated kernels immediately and reboot to effect the fixes.

In addition to these security fixes, other fixes have been included such as :

  - added support for new devices: o Testo products in     usb-serial o ATI SB600 IDE o ULI M-1573 south Bridge o     PATA and SATA support for nVidia MCP55, MCP61, MCP65,     and AMD CS5536 o Asus W6A motherboard in snd-hda-intel o     bcm 5780

  - fixed ip_gre module unload OOPS

    - enabled opti621 driver for x86 and x86_64

    - fixed a local DoS introduced by an imcomplete fix for       CVE-2006-2445

    - updated to Xen 3.0.1 with selected fixes

    - enable hugetlbfs

To update your kernel, please follow the directions located at :

http://www.mandriva.com/en/security/kernelupdate

This advisory covers the S/390 components of the recent security update for the Linux 2.6.8 kernel that were missing due to technical problems. For reference, please see the text of the original advisory.

  Several security related problems have been discovered in the Linux   kernel which may lead to a denial of service or even the execution   of arbitrary code. The Common Vulnerabilities and Exposures project   identifies the following problems :

    - CVE-2004-2660       Toshihiro Iwamoto discovered a memory leak in the       handling of direct I/O writes that allows local users       to cause a denial of service.

    - CVE-2005-4798       A buffer overflow in NFS readlink handling allows a       malicious remote server to cause a denial of service.

    - CVE-2006-1052       Stephen Smalley discovered a bug in the SELinux ptrace       handling that allows local users with ptrace       permissions to change the tracer SID to the SID of       another process.

    - CVE-2006-1343       Pavel Kankovsky discovered an information leak in the       getsockopt system call which can be exploited by a       local program to leak potentially sensitive memory to       userspace.

    - CVE-2006-1528       Douglas Gilbert reported a bug in the sg driver that       allows local users to cause a denial of service by       performing direct I/O transfers from the sg driver to       memory mapped I/O space.

    - CVE-2006-1855       Mattia Belletti noticed that certain debugging code       left in the process management code could be exploited       by a local attacker to cause a denial of service.

    - CVE-2006-1856       Kostik Belousov discovered a missing LSM       file_permission check in the readv and writev       functions which might allow attackers to bypass       intended access restrictions.

    - CVE-2006-2444       Patrick McHardy discovered a bug in the SNMP NAT       helper that allows remote attackers to cause a denial       of service.

    - CVE-2006-2446       A race condition in the socket buffer handling allows       remote attackers to cause a denial of service.

    - CVE-2006-2935       Diego Calleja Garcia discovered a buffer overflow in       the DVD handling code that could be exploited by a       specially crafted DVD USB storage device to execute       arbitrary code.

    - CVE-2006-2936       A bug in the serial USB driver has been discovered       that could be exploited by a custom made USB serial       adapter to consume arbitrary amounts of memory.

    - CVE-2006-3468       James McKenzie discovered a denial of service       vulnerability in the NFS driver. When exporting an       ext3 file system over NFS, a remote attacker could       exploit this to trigger a file system panic by sending       a specially crafted UDP packet.

    - CVE-2006-3745       Wei Wang discovered a bug in the SCTP implementation       that allows local users to cause a denial of service       and possibly gain root privileges.

    - CVE-2006-4093       Olof Johansson discovered that the kernel does not       disable the HID0 bit on PowerPC 970 processors which       could be exploited by a local attacker to cause a       denial of service.

    - CVE-2006-4145       A bug in the Universal Disk Format (UDF) filesystem       driver could be exploited by a local user to cause a       denial of service.

    - CVE-2006-4535       David Miller reported a problem with the fix for       CVE-2006-3745 that allows local users to crash the       system via an SCTP socket with a certain SO_LINGER       value.

The following matrix explains which kernel version for which architecture fixes the problem mentioned above :

                              stable (sarge)                 Source                       2.6.8-16sarge5                 Alpha architecture           2.6.8-16sarge5                 AMD64 architecture           2.6.8-16sarge5                 HP Precision architecture    2.6.8-6sarge5                  Intel IA-32 architecture     2.6.8-16sarge5                 Intel IA-64 architecture     2.6.8-14sarge5                 Motorola 680x0 architecture  2.6.8-4sarge5                  PowerPC architecture         2.6.8-12sarge5                 IBM S/390                    2.6.8-5sarge5                  Sun Sparc architecture       2.6.8-15sarge5                 FAI                          1.9.1sarge4

Updated kernel packages that fix several security issues in the Red Hat Enterprise Linux 4 kernel are now available.

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

The Linux kernel handles the basic functions of the operating system.

These new kernel packages contain fixes for the security issues described below :

* a flaw in the proc file system that allowed a local user to use a suid-wrapper for scripts to gain root privileges (CVE-2006-3626, Important)

* a flaw in the SCTP implementation that allowed a local user to cause a denial of service (panic) or to possibly gain root privileges (CVE-2006-3745, Important)

* a flaw in NFS exported ext2/ext3 partitions when handling invalid inodes that allowed a remote authenticated user to cause a denial of service (filesystem panic) (CVE-2006-3468, Important)

* a flaw in the restore_all code path of the 4/4GB split support of non-hugemem kernels that allowed a local user to cause a denial of service (panic) (CVE-2006-2932, Important)

* a flaw in IPv4 netfilter handling for the unlikely use of SNMP NAT processing that allowed a remote user to cause a denial of service (crash) or potential memory corruption (CVE-2006-2444, Moderate)

* a flaw in the DVD handling of the CDROM driver that could be used together with a custom built USB device to gain root privileges (CVE-2006-2935, Moderate)

* a flaw in the handling of O_DIRECT writes that allowed a local user to cause a denial of service (memory consumption) (CVE-2004-2660, Low)

* a flaw in the SCTP chunk length handling that allowed a remote user to cause a denial of service (crash) (CVE-2006-1858, Low)

* a flaw in the input handling of the ftdi_sio driver that allowed a local user to cause a denial of service (memory consumption) (CVE-2006-2936, Low)

In addition a bugfix was added to enable a clean reboot for the IBM Pizzaro machines.

Red Hat would like to thank Wei Wang of McAfee Avert Labs and Kirill Korotaev for reporting issues fixed in this erratum.

All Red Hat Enterprise Linux 4 users are advised to upgrade their kernels to the packages associated with their machine architectures and configurations as listed in this erratum.

The remote CentOS system is missing a security update which has been documented in Red Hat advisory RHSA-2006-0617.

ID	Name	Product	Family	Severity
67401	Oracle Linux 4 : kernel (ELSA-2006-0617 / ELSA-2006-0689)	Nessus	Oracle Linux Local Security Checks	high
59121	SuSE 10 Security Update : Linux kernel (x86_64) (ZYPP Patch Number 2096)	Nessus	SuSE Local Security Checks	high
29485	SuSE 10 Security Update : Linux kernel (i386) (ZYPP Patch Number 2097)	Nessus	SuSE Local Security Checks	high
27925	Ubuntu 5.04 / 5.10 / 6.06 LTS : linux-source-2.6.10/-2.6.12/-2.6.15 vulnerabilities (USN-346-1)	Nessus	Ubuntu Local Security Checks	high
27290	openSUSE 10 Security Update : kernel (kernel-2099)	Nessus	SuSE Local Security Checks	high
23897	Mandrake Linux Security Advisory : kernel (MDKSA-2006:151)	Nessus	Mandriva Local Security Checks	high
22726	Debian DSA-1184-2 : kernel-source-2.6.8 - several vulnerabilities	Nessus	Debian Local Security Checks	high
22279	CentOS 4 : kernel (CESA-2006:0617)	Nessus	CentOS Local Security Checks	high
22264	RHEL 4 : kernel (RHSA-2006:0617)	Nessus	Red Hat Local Security Checks	high
801421	CentOS RHSA-2006-0617 Security Check	Log Correlation Engine	Generic	high

Detections

Analytics

CVE-2006-3468

medium

Tenable Plugins

high

high

high

high

high

high

high

high

high

high