The compat_alloc_user_space functions in include/asm/compat.h files in the Linux kernel before 2.6.36-rc4-git2 on 64-bit platforms do not properly allocate the userspace memory required for the 32-bit compatibility layer, which allows local users to gain privileges by leveraging the ability of the compat_mc_getsockopt function (aka the MCAST_MSFILTER getsockopt support) to control a certain length value, related to a "stack pointer underflow" issue, as exploited in the wild in September 2010.

The actions implementation in the network queueing functionality in the Linux kernel before 2.6.36-rc2 does not properly initialize certain structure members when performing dump operations, which allows local users to obtain potentially sensitive information from kernel memory via vectors related to (1) the tcf_gact_dump function in net/sched/act_gact.c, (2) the tcf_mirred_dump function in net/sched/act_mirred.c, (3) the tcf_nat_dump function in net/sched/act_nat.c, (4) the tcf_simp_dump function in net/sched/act_simple.c, and (5) the tcf_skbedit_dump function in net/sched/act_skbedit.c.

The xfs_ioc_fsgetxattr function in fs/xfs/linux-2.6/xfs_ioctl.c in the Linux kernel before 2.6.36-rc4 does not initialize a certain structure member, which allows local users to obtain potentially sensitive information from kernel stack memory via an ioctl call.

The DNS resolution functionality in the CIFS implementation in the Linux kernel before 2.6.35, when CONFIG_CIFS_DFS_UPCALL is enabled, relies on a user's keyring for the dns_resolver upcall in the cifs.upcall userspace helper, which allows local users to spoof the results of DNS queries and perform arbitrary CIFS mounts via vectors involving an add_key call, related to a "cache stuffing" issue and MS-DFS referrals.

The gfs2_dirent_find_space function in fs/gfs2/dir.c in the Linux kernel before 2.6.35 uses an incorrect size value in calculations associated with sentinel directory entries, which allows local users to cause a denial of service (NULL pointer dereference and panic) and possibly have unspecified other impact by renaming a file in a GFS2 filesystem, related to the gfs2_rename function in fs/gfs2/ops_inode.c.

The mext_check_arguments function in fs/ext4/move_extent.c in the Linux kernel before 2.6.35 allows local users to overwrite an append-only file via a MOVE_EXT ioctl call that specifies this file as a donor.

Buffer overflow in the ecryptfs_uid_hash macro in fs/ecryptfs/messaging.c in the eCryptfs subsystem in the Linux kernel before 2.6.35 might allow local users to gain privileges or cause a denial of service (system crash) via unspecified vectors.