Description
The xsave/xrstor implementation in arch/x86/include/asm/xsave.h in the Linux kernel before 3.19.2 creates certain .altinstr_replacement pointers and consequently does not provide any protection against instruction faulting, which allows local users to cause a denial of service (panic) by triggering a fault, as demonstrated by an unaligned memory operand or a non-canonical address memory operand.
References
- http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.19.2
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=06c8173eb92bbfc03a0fe8bb64315857d0badd06
- https://github.com/torvalds/linux/commit/06c8173eb92bbfc03a0fe8bb64315857d0badd06
- [oss-security] 20150321 Re: CVE Request: Linux kernel unprivileged denial-of-service due to mis-protected xsave/xrstor instructions. mailing-list
- https://bugzilla.redhat.com/show_bug.cgi?id=1204729