Commit 2c87767c authored by Kyle Huey's avatar Kyle Huey Committed by Dave Hansen
Browse files

x86/fpu: Add a pkru argument to copy_uabi_to_xstate() 



In preparation for moving PKRU handling code out of
fpu_copy_uabi_to_guest_fpstate() and into copy_uabi_to_xstate(), add an
argument that copy_uabi_from_kernel_to_xstate() can use to pass the
canonical location of the PKRU value. For
copy_sigframe_from_user_to_xstate() the kernel will actually restore the
PKRU value from the fpstate, but pass in the thread_struct's pkru location
anyways for consistency.

Signed-off-by: default avatarKyle Huey <me@kylehuey.com>
Signed-off-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20221115230932.7126-4-khuey%40kylehuey.com
parent 1c813ce0

arch/x86/kernel/fpu/xstate.c

+13 −3
Original line number Diff line number Diff line
@@ -1200,8 +1200,18 @@ static int copy_from_buffer(void *dst, unsigned int offset, unsigned int size, 
}





/**

 * copy_uabi_to_xstate - Copy a UABI format buffer to the kernel xstate

 * @fpstate:	The fpstate buffer to copy to

 * @kbuf:	The UABI format buffer, if it comes from the kernel

 * @ubuf:	The UABI format buffer, if it comes from userspace

 * @pkru:	unused

 *

 * Converts from the UABI format into the kernel internal hardware

 * dependent format.

 */

static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf,

			       const void __user *ubuf)

			       const void __user *ubuf, u32 *pkru)

{

	struct xregs_state *xsave = &fpstate->regs.xsave;

	unsigned int offset, size;
@@ -1270,7 +1280,7 @@ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf, 
 */

int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u32 *pkru)

{

	return copy_uabi_to_xstate(fpstate, kbuf, NULL);

	return copy_uabi_to_xstate(fpstate, kbuf, NULL, pkru);

}



/*
@@ -1281,7 +1291,7 @@ int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u 
int copy_sigframe_from_user_to_xstate(struct task_struct *tsk,

				      const void __user *ubuf)

{

	return copy_uabi_to_xstate(tsk->thread.fpu.fpstate, NULL, ubuf);

	return copy_uabi_to_xstate(tsk->thread.fpu.fpstate, NULL, ubuf, &tsk->thread.pkru);

}



static bool validate_independent_components(u64 mask)