Unverified Commit c5203cb7 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!4781 x86/fpu: Stop relying on userspace for info to fault in xsave buffer 

Merge Pull Request from: @ci-robot 
 
PR sync from: liwei <liwei728@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/XJI3ZTTW6GXTNMULPOSXZLG4Q3D23MUB/ 
 
https://gitee.com/src-openeuler/kernel/issues/I93HD8 
 
Link:https://gitee.com/openeuler/kernel/pulls/4781

 

Reviewed-by: default avatarWei Li <liwei391@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parents 4f032dd1 2224c682

arch/x86/kernel/fpu/signal.c

+5 −8
Original line number Diff line number Diff line
@@ -274,12 +274,13 @@ static int __restore_fpregs_from_user(void __user *buf, u64 ufeatures, 
 * Attempt to restore the FPU registers directly from user memory.

 * Pagefaults are handled and any errors returned are fatal.

 */

static bool restore_fpregs_from_user(void __user *buf, u64 xrestore,

				     bool fx_only, unsigned int size)

static bool restore_fpregs_from_user(void __user *buf, u64 xrestore, bool fx_only)

{

	struct fpu *fpu = &current->thread.fpu;

	int ret;



	/* Restore enabled features only. */

	xrestore &= fpu->fpstate->user_xfeatures;

retry:

	fpregs_lock();

	/* Ensure that XFD is up to date */
@@ -309,7 +310,7 @@ static bool restore_fpregs_from_user(void __user *buf, u64 xrestore, 
		if (ret != X86_TRAP_PF)

			return false;



		if (!fault_in_readable(buf, size))

		if (!fault_in_readable(buf, fpu->fpstate->user_size))

			goto retry;

		return false;

	}
@@ -339,7 +340,6 @@ static bool __fpu_restore_sig(void __user *buf, void __user *buf_fx, 
	struct user_i387_ia32_struct env;

	bool success, fx_only = false;

	union fpregs_state *fpregs;

	unsigned int state_size;

	u64 user_xfeatures = 0;



	if (use_xsave()) {
@@ -349,17 +349,14 @@ static bool __fpu_restore_sig(void __user *buf, void __user *buf_fx, 
			return false;



		fx_only = !fx_sw_user.magic1;

		state_size = fx_sw_user.xstate_size;

		user_xfeatures = fx_sw_user.xfeatures;

	} else {

		user_xfeatures = XFEATURE_MASK_FPSSE;

		state_size = fpu->fpstate->user_size;

	}



	if (likely(!ia32_fxstate)) {

		/* Restore the FPU registers directly from user memory. */

		return restore_fpregs_from_user(buf_fx, user_xfeatures, fx_only,

						state_size);

		return restore_fpregs_from_user(buf_fx, user_xfeatures, fx_only);

	}



	/*