Description

The x86/fpu (Floating Point Unit) subsystem in the Linux kernel before 4.13.5, when a processor supports the xsave feature but not the xsaves feature, does not correctly handle attempts to set reserved bits in the xstate header via the ptrace() or rt_sigreturn() system call, allowing local users to read the FPU registers of other processes on the system, related to arch/x86/kernel/fpu/regset.c and arch/x86/kernel/fpu/signal.c.

References

http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=814fb7bb7db5433757d76f4c4502c96fc53b0b5e

http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.13.5

https://github.com/torvalds/linux/commit/814fb7bb7db5433757d76f4c4502c96fc53b0b5e

https://source.android.com/security/bulletin/pixel/2018-01-01

Details

Risk Information

CVSS v2

CVSS v3