low
1.2
CWE
NVD-CWE-Other 476
Advisory Published
CVE Published
Updated

CVE-2008-7256: Null Pointer Dereference

First published: Wed May 26 2010(Updated: )

Description of problem: knfsd crashes if you are using it to export shmemfs objects and run strict overcommit. In this situation the current-&gt;mm based modifier to the overcommit goes through a NULL pointer. We could simply check for NULL and skip the modifier but we've caught other real bugs in the past from mm being NULL here - cases where we did need a valid mm set up (eg the exec bug in 2005). To preserve the checks and get the logic we want shuffle the checking around and add a new helper to the vm_ security wrappers Also fix a current-&gt;mm reference in nommu that should use the passed mm Upstream commit: nfsd: fix vm overcommit crash <a href="http://git.kernel.org/linus/731572d39fcd3498702eda4600db4c43d51e0b26">http://git.kernel.org/linus/731572d39fcd3498702eda4600db4c43d51e0b26</a> nfsd: fix vm overcommit crash fix #2 <a href="http://git.kernel.org/linus/1b79cd04fab80be61dcd2732e2423aafde9a4c1c">http://git.kernel.org/linus/1b79cd04fab80be61dcd2732e2423aafde9a4c1c</a> Reference: [PATCH] knfsd: add nfs-export support to tmpfs <a href="http://git.kernel.org/linus/91828a405ae454a9503c41a7744f6ff877a80714">http://git.kernel.org/linus/91828a405ae454a9503c41a7744f6ff877a80714</a>

Credit: cve@mitre.org cve@mitre.org

Affected SoftwareAffected VersionHow to fix
Linux Kernel<=2.6.28
Linux Kernel=2.6.0
Linux Kernel=2.6.1
Linux Kernel=2.6.2
Linux Kernel=2.6.10
Linux Kernel=2.6.11
Linux Kernel=2.6.11.1
Linux Kernel=2.6.11.2
Linux Kernel=2.6.11.3
Linux Kernel=2.6.11.4
Linux Kernel=2.6.11.5
Linux Kernel=2.6.11.6
Linux Kernel=2.6.11.7
Linux Kernel=2.6.11.8
Linux Kernel=2.6.11.9
Linux Kernel=2.6.11.10
Linux Kernel=2.6.11.11
Linux Kernel=2.6.11.12
Linux Kernel=2.6.12
Linux Kernel=2.6.12.1
Linux Kernel=2.6.12.2
Linux Kernel=2.6.12.3
Linux Kernel=2.6.12.4
Linux Kernel=2.6.12.5
Linux Kernel=2.6.12.6
Linux Kernel=2.6.13
Linux Kernel=2.6.13.1
Linux Kernel=2.6.13.2
Linux Kernel=2.6.13.3
Linux Kernel=2.6.13.4
Linux Kernel=2.6.13.5
Linux Kernel=2.6.14
Linux Kernel=2.6.14.1
Linux Kernel=2.6.14.2
Linux Kernel=2.6.14.3
Linux Kernel=2.6.14.4
Linux Kernel=2.6.14.5
Linux Kernel=2.6.14.6
Linux Kernel=2.6.14.7
Linux Kernel=2.6.15
Linux Kernel=2.6.15.1
Linux Kernel=2.6.15.2
Linux Kernel=2.6.15.3
Linux Kernel=2.6.15.4
Linux Kernel=2.6.15.5
Linux Kernel=2.6.15.6
Linux Kernel=2.6.15.7
Linux Kernel=2.6.16
Linux Kernel=2.6.16.1
Linux Kernel=2.6.16.2
Linux Kernel=2.6.16.3
Linux Kernel=2.6.16.4
Linux Kernel=2.6.16.5
Linux Kernel=2.6.16.6
Linux Kernel=2.6.16.7
Linux Kernel=2.6.16.8
Linux Kernel=2.6.16.9
Linux Kernel=2.6.16.10
Linux Kernel=2.6.16.11
Linux Kernel=2.6.16.12
Linux Kernel=2.6.16.13
Linux Kernel=2.6.16.14
Linux Kernel=2.6.16.15
Linux Kernel=2.6.16.16
Linux Kernel=2.6.16.17
Linux Kernel=2.6.16.18
Linux Kernel=2.6.16.19
Linux Kernel=2.6.16.20
Linux Kernel=2.6.16.21
Linux Kernel=2.6.16.22
Linux Kernel=2.6.16.23
Linux Kernel=2.6.16.24
Linux Kernel=2.6.16.25
Linux Kernel=2.6.16.26
Linux Kernel=2.6.16.27
Linux Kernel=2.6.16.28
Linux Kernel=2.6.16.29
Linux Kernel=2.6.16.30
Linux Kernel=2.6.16.31
Linux Kernel=2.6.16.32
Linux Kernel=2.6.16.33
Linux Kernel=2.6.16.34
Linux Kernel=2.6.16.35
Linux Kernel=2.6.16.36
Linux Kernel=2.6.16.37
Linux Kernel=2.6.16.38
Linux Kernel=2.6.16.39
Linux Kernel=2.6.16.40
Linux Kernel=2.6.16.41
Linux Kernel=2.6.16.42
Linux Kernel=2.6.16.43
Linux Kernel=2.6.16.44
Linux Kernel=2.6.16.45
Linux Kernel=2.6.16.46
Linux Kernel=2.6.16.47
Linux Kernel=2.6.16.48
Linux Kernel=2.6.16.49
Linux Kernel=2.6.16.50
Linux Kernel=2.6.16.51
Linux Kernel=2.6.16.52
Linux Kernel=2.6.16.53
Linux Kernel=2.6.16.54
Linux Kernel=2.6.16.55
Linux Kernel=2.6.16.56
Linux Kernel=2.6.16.57
Linux Kernel=2.6.16.58
Linux Kernel=2.6.16.59
Linux Kernel=2.6.16.60
Linux Kernel=2.6.16.61
Linux Kernel=2.6.16.62
Linux Kernel=2.6.17
Linux Kernel=2.6.17.1
Linux Kernel=2.6.17.2
Linux Kernel=2.6.17.3
Linux Kernel=2.6.17.4
Linux Kernel=2.6.17.5
Linux Kernel=2.6.17.6
Linux Kernel=2.6.17.7
Linux Kernel=2.6.17.8
Linux Kernel=2.6.17.9
Linux Kernel=2.6.17.10
Linux Kernel=2.6.17.11
Linux Kernel=2.6.17.12
Linux Kernel=2.6.17.13
Linux Kernel=2.6.17.14
Linux Kernel=2.6.18
Linux Kernel=2.6.18.1
Linux Kernel=2.6.18.2
Linux Kernel=2.6.18.3
Linux Kernel=2.6.18.4
Linux Kernel=2.6.18.5
Linux Kernel=2.6.18.6
Linux Kernel=2.6.18.7
Linux Kernel=2.6.18.8
Linux Kernel=2.6.19
Linux Kernel=2.6.19.1
Linux Kernel=2.6.19.2
Linux Kernel=2.6.19.3
Linux Kernel=2.6.19.4
Linux Kernel=2.6.19.5
Linux Kernel=2.6.19.6
Linux Kernel=2.6.19.7
Linux Kernel=2.6.20
Linux Kernel=2.6.20.1
Linux Kernel=2.6.20.2
Linux Kernel=2.6.20.3
Linux Kernel=2.6.20.4
Linux Kernel=2.6.20.5
Linux Kernel=2.6.20.6
Linux Kernel=2.6.20.7
Linux Kernel=2.6.20.8
Linux Kernel=2.6.20.9
Linux Kernel=2.6.20.10
Linux Kernel=2.6.20.11
Linux Kernel=2.6.20.12
Linux Kernel=2.6.20.13
Linux Kernel=2.6.20.14
Linux Kernel=2.6.20.15
Linux Kernel=2.6.20.16
Linux Kernel=2.6.20.17
Linux Kernel=2.6.20.18
Linux Kernel=2.6.20.19
Linux Kernel=2.6.20.20
Linux Kernel=2.6.20.21
Linux Kernel=2.6.21
Linux Kernel=2.6.21.1
Linux Kernel=2.6.21.2
Linux Kernel=2.6.21.3
Linux Kernel=2.6.21.4
Linux Kernel=2.6.21.5
Linux Kernel=2.6.21.6
Linux Kernel=2.6.21.7
Linux Kernel=2.6.22
Linux Kernel=2.6.22.1
Linux Kernel=2.6.22.2
Linux Kernel=2.6.22.3
Linux Kernel=2.6.22.4
Linux Kernel=2.6.22.5
Linux Kernel=2.6.22.6
Linux Kernel=2.6.22.7
Linux Kernel=2.6.22.8
Linux Kernel=2.6.22.9
Linux Kernel=2.6.22.10
Linux Kernel=2.6.22.11
Linux Kernel=2.6.22.12
Linux Kernel=2.6.22.13
Linux Kernel=2.6.22.14
Linux Kernel=2.6.22.15
Linux Kernel=2.6.22.16
Linux Kernel=2.6.22.17
Linux Kernel=2.6.22.18
Linux Kernel=2.6.22.19
Linux Kernel=2.6.22.20
Linux Kernel=2.6.22.21
Linux Kernel=2.6.22.22
Linux Kernel=2.6.23
Linux Kernel=2.6.23.1
Linux Kernel=2.6.23.2
Linux Kernel=2.6.23.3
Linux Kernel=2.6.23.4
Linux Kernel=2.6.23.5
Linux Kernel=2.6.23.6
Linux Kernel=2.6.23.7
Linux Kernel=2.6.23.8
Linux Kernel=2.6.23.9
Linux Kernel=2.6.23.10
Linux Kernel=2.6.23.11
Linux Kernel=2.6.23.12
Linux Kernel=2.6.23.13
Linux Kernel=2.6.23.14
Linux Kernel=2.6.23.15
Linux Kernel=2.6.23.16
Linux Kernel=2.6.23.17
Linux Kernel=2.6.24
Linux Kernel=2.6.24.1
Linux Kernel=2.6.24.2
Linux Kernel=2.6.24.3
Linux Kernel=2.6.24.4
Linux Kernel=2.6.24.5
Linux Kernel=2.6.24.6
Linux Kernel=2.6.24.7
Linux Kernel=2.6.25
Linux Kernel=2.6.25.1
Linux Kernel=2.6.25.2
Linux Kernel=2.6.25.3
Linux Kernel=2.6.25.4
Linux Kernel=2.6.25.5
Linux Kernel=2.6.25.6
Linux Kernel=2.6.25.7
Linux Kernel=2.6.25.8
Linux Kernel=2.6.25.9
Linux Kernel=2.6.25.10
Linux Kernel=2.6.25.11
Linux Kernel=2.6.25.12
Linux Kernel=2.6.25.13
Linux Kernel=2.6.25.14
Linux Kernel=2.6.25.15
Linux Kernel=2.6.25.16
Linux Kernel=2.6.25.17
Linux Kernel=2.6.25.18
Linux Kernel=2.6.25.19
Linux Kernel=2.6.25.20
Linux Kernel=2.6.27
Linux Kernel=2.6.27-rc1
Linux Kernel=2.6.27-rc2
Linux Kernel=2.6.27-rc3
Linux Kernel=2.6.27-rc4
Linux Kernel=2.6.27-rc5
Linux Kernel=2.6.27-rc6
Linux Kernel=2.6.27-rc7
Linux Kernel=2.6.27-rc8
Linux Kernel=2.6.27-rc9
Linux Kernel=2.6.27.1
Linux Kernel=2.6.27.2
Linux Kernel=2.6.27.3
Linux Kernel=2.6.27.4
Linux Kernel=2.6.27.5
Linux Kernel=2.6.27.6
Linux Kernel=2.6.27.7
Linux Kernel=2.6.27.8
Linux Kernel=2.6.27.9
Linux Kernel=2.6.27.10
Linux Kernel=2.6.27.11
Linux Kernel=2.6.27.12
Linux Kernel=2.6.27.13
Linux Kernel=2.6.27.14
Linux Kernel=2.6.27.15
Linux Kernel=2.6.27.16
Linux Kernel=2.6.27.17
Linux Kernel=2.6.27.18
Linux Kernel=2.6.27.19
Linux Kernel=2.6.27.20
Linux Kernel=2.6.27.21
Linux Kernel=2.6.27.22
Linux Kernel=2.6.27.23
Linux Kernel=2.6.27.24
Linux Kernel=2.6.27.25
Linux Kernel=2.6.27.26
Linux Kernel=2.6.27.27
Linux Kernel=2.6.27.28
Linux Kernel=2.6.27.29
Linux Kernel=2.6.27.30
Linux Kernel=2.6.27.31
Linux Kernel=2.6.27.32
Linux Kernel=2.6.27.33
Linux Kernel=2.6.27.34
Linux Kernel=2.6.27.35
Linux Kernel=2.6.27.36
Linux Kernel=2.6.27.37
Linux Kernel=2.6.27.38
Linux Kernel=2.6.27.39
Linux Kernel=2.6.27.40
Linux Kernel=2.6.27.41
Linux Kernel=2.6.27.42
Linux Kernel=2.6.27.43
Linux Kernel=2.6.27.44
Linux Kernel=2.6.27.45
Linux Kernel=2.6.28-rc1
Linux Kernel=2.6.28-rc2
Linux Kernel=2.6.28-rc3
Linux Kernel=2.6.28-rc4
Linux Kernel=2.6.28-rc5
Linux Kernel=2.6.28-rc6

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2008-7256?

    CVE-2008-7256 is classified as a moderate severity vulnerability.

  • How do I fix CVE-2008-7256?

    To mitigate CVE-2008-7256, consider upgrading to a later version of the Linux kernel beyond 2.6.28.

  • What types of systems are affected by CVE-2008-7256?

    CVE-2008-7256 affects Linux systems using the knfsd to export shmemfs objects with strict overcommit enabled.

  • Is CVE-2008-7256 a remote vulnerability?

    CVE-2008-7256 is not a remote vulnerability as it requires local access to the affected system.

  • What are the symptoms of CVE-2008-7256 exploitation?

    Exploitation of CVE-2008-7256 may result in crashes of the knfsd service when handling specific memory clear requests.

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