Candidate: CVE-2009-2847 Description: do_sigaltstack: avoid copying 'stack_t' as a structure to user space . Ulrich Drepper correctly points out that there is generally padding in the structure on 64-bit hosts, and that copying the structure from kernel to user space can leak information from the kernel stack in those padding bytes. . Avoid the whole issue by just copying the three members one by one instead, which also means that the function also can avoid the need for a stack frame. This also happens to match how we copy the new structure from user space, so it all even makes sense. References: http://git.kernel.org/linus/0083fc2c50e6c5127c2802ad323adf8143ab7856 https://bugzilla.redhat.com/show_bug.cgi?id=515392 http://milw0rm.com/exploits/9352 Ubuntu-Description: Notes: Bugs: upstream: released (2.6.31-rc6) [0083fc2] linux-2.6: released (2.6.30-6) [bugfix/all/do_sigaltstack-avoid-copying-stack_t-as-a-structure-to-userspace.patch] 2.6.18-etch-security: released (2.6.18.dfsg.1-24etch4) [bugfix/all/do_sigaltstack-avoid-copying-stack_t-as-a-structure-to-userspace.patch] 2.6.24-etch-security: released (2.6.24-6~etchnhalf.9etch1) [bugfix/all/do_sigaltstack-avoid-copying-stack_t-as-a-structure-to-userspace.patch] 2.6.26-lenny-security: released (2.6.26-19) [bugfix/all/do_sigaltstack-avoid-copying-stack_t-as-a-structure-to-userspace.patch]