x86/entry/64/compat: Clear registers for compat syscalls, to reduce speculation attack surface

At entry userspace may have populated registers with values that could
otherwise be useful in a speculative execution attack. Clear them to
minimize the kernel's attack surface.

Originally-From: Andi Kleen <[email protected]>
Signed-off-by: Dan Williams <[email protected]>
Cc: <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/151787989697.7847.4083702787288600552.stgit@dwillia2-desk3.amr.corp.intel.com
[ Made small improvements to the changelog. ]
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions