From: Eric Biggers <[email protected]> This is in preparation to verify the full xstate header as supplied by user-space.
Signed-off-by: Eric Biggers <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Kees Cook <[email protected]> Cc: Kevin Hao <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Michael Halcrow <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Wanpeng Li <[email protected]> Cc: Yu-cheng Yu <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/fpu/xstate.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 2427aeea33b5..02591b96bb25 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1148,11 +1148,13 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) int i; u64 xfeatures; u64 allowed_features; + struct xstate_header hdr; offset = offsetof(struct xregs_state, header); - size = sizeof(xfeatures); + size = sizeof(hdr); - memcpy(&xfeatures, kbuf + offset, size); + memcpy(&hdr, kbuf + offset, size); + xfeatures = hdr.xfeatures; /* * Reject if the user sets any disabled or supervisor features: -- 2.11.0
