Description: x86/fpu: Don't let userspace set bogus xcomp_bv
References:
Notes:
 carnil> Introduced in 3.17-rc1 with 0b29643a58439dc9a8b0c0cacad0e7cb608c8199
Bugs:
upstream: released (4.14-rc3) [814fb7bb7db5433757d76f4c4502c96fc53b0b5e]
4.9-upstream-stable: released (4.9.53) [5e9b07f30d21295b83f2024ffb5a349d3af6f749]
3.16-upstream-stable: N/A "Vulnerable code introduced in 3.17-rc1"
3.2-upstream-stable: N/A "Vulnerable code introduced in 3.17-rc1"
sid: released (4.13.10-1)
4.9-stretch-security: released (4.9.65-1)
3.16-jessie-security: N/A "Vulnerable code introduced later"
3.2-wheezy-security: N/A "Vulnerable code introduced later"