The pci_register_iommu_region function in arch/sparc/kernel/pci_common.c in the Linux kernel before 2.6.29 on the sparc64 platform allows local users to cause a denial of service (system crash) by reading the /proc/iomem file, related to uninitialized pointers and the request_resource function.
https://exchange.xforce.ibmcloud.com/vulnerabilities/51196
http://www.ubuntu.com/usn/usn-793-1
http://www.securityfocus.com/bid/35415
http://www.openwall.com/lists/oss-security/2009/06/03/3
http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.29
http://www.debian.org/security/2009/dsa-1844
http://secunia.com/advisories/36051