The llc_ui_getname function in net/llc/af_llc.c in the Linux kernel 2.6.31-rc7 and earlier does not initialize a certain data structure, which allows local users to read the contents of some kernel memory locations by calling getsockname on an AF_LLC socket.

The Linux kernel before 2.6.31-rc7 does not properly prevent mmap operations that target page zero and other low memory addresses, which allows local users to gain privileges by exploiting NULL pointer dereference vulnerabilities, related to (1) the default configuration of the allow_unconfined_mmap_low boolean in SELinux on Red Hat Enterprise Linux (RHEL) 5, (2) an error that causes allow_unconfined_mmap_low to be ignored in the unconfined_t domain, (3) lack of a requirement for the CAP_SYS_RAWIO capability for these mmap operations, and (4) interaction between the mmap_min_addr protection mechanism and certain application programs.

The Linux kernel before 2.6.31-rc7 does not initialize certain data structures within getname functions, which allows local users to read the contents of some kernel memory locations by calling getsockname on (1) an AF_APPLETALK socket, related to the atalk_getname function in net/appletalk/ddp.c; (2) an AF_IRDA socket, related to the irda_getname function in net/irda/af_irda.c; (3) an AF_ECONET socket, related to the econet_getname function in net/econet/af_econet.c; (4) an AF_NETROM socket, related to the nr_getname function in net/netrom/af_netrom.c; (5) an AF_ROSE socket, related to the rose_getname function in net/rose/af_rose.c; or (6) a raw CAN socket, related to the raw_getname function in net/can/raw.c.

The eisa_eeprom_read function in the parisc isa-eeprom component (drivers/parisc/eisa_eeprom.c) in the Linux kernel before 2.6.31-rc6 allows local users to access restricted memory via a negative ppos argument, which bypasses a check that assumes that ppos is positive and causes an out-of-bounds read in the readb function.

The load_flat_shared_library function in fs/binfmt_flat.c in the flat subsystem in the Linux kernel before 2.6.31-rc6 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by executing a shared flat binary, which triggers an access of an "uninitialized cred pointer."

The personality subsystem in the Linux kernel before 2.6.31-rc3 has a PER_CLEAR_ON_SETID setting that does not clear the ADDR_COMPAT_LAYOUT and MMAP_PAGE_ZERO flags when executing a setuid or setgid program, which makes it easier for local users to leverage the details of memory usage to (1) conduct NULL pointer dereference attacks, (2) bypass the mmap_min_addr protection mechanism, or (3) defeat address space layout randomization (ASLR).