Integer overflows were discovered in the functions grubcmdinitrd and grubinitrdinit in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not included in GRUB2 upstream), leading to a heap-based buffer overflow. These could be triggered by an extremely large number of arguments to the initrd command on 32-bit architectures, or a crafted filesystem with very large files on any architecture. An attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. This issue affects GRUB2 version 2.04 and prior versions.

"grub2 contains a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing."

GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed. This only affects systems where the kernel signing certificate has been imported directly into the secure boot database and the GRUB image is booted directly without the use of shim. This issue affects GRUB2 version 2.04 and prior versions.

Description of problem: We leak at least 32bits of kernel memory to user land in tc dump, because we dont init all fields (capab ?) of the dumped structure.

Use C99 initializers so that holes and non explicit fields are zeroed.

http://patchwork.ozlabs.org/patch/61857/