x86/pkeys: Change caller of update_pkru_in_sigframe()

[ Upstream commit 6a1853b ]

update_pkru_in_sigframe() will shortly need some information which
is only available inside xsave_to_user_sigframe(). Move
update_pkru_in_sigframe() inside the other function to make it
easier to provide it that information.

No functional changes.

Signed-off-by: Aruna Ramakrishna <[email protected]>
Signed-off-by: Dave Hansen <[email protected]>
Link: https://lore.kernel.org/all/20241119174520.3987538-2-aruna.ramakrishna%40oracle.com
Stable-dep-of: ae6012d ("x86/pkeys: Ensure updated PKRU value is XRSTOR'd")
Signed-off-by: Sasha Levin <[email protected]>

Author: arunar

arch/x86/kernel/fpu/signal.c

@@ -63,16 +63,6 @@ static inline bool check_xstate_in_sigframe(struct fxregs_state __user *fxbuf,
 	return true;
 }
 
-/*
- * Update the value of PKRU register that was already pushed onto the signal frame.
- */
-static inline int update_pkru_in_sigframe(struct xregs_state __user *buf, u32 pkru)
-{
-	if (unlikely(!cpu_feature_enabled(X86_FEATURE_OSPKE)))
-		return 0;
-	return __put_user(pkru, (unsigned int __user *)get_xsave_addr_user(buf, XFEATURE_PKRU));
-}
-
 /*
  * Signal frame handlers.
  */
@@ -168,14 +158,8 @@ static inline bool save_xstate_epilog(void __user *buf, int ia32_frame,
 
 static inline int copy_fpregs_to_sigframe(struct xregs_state __user *buf, u32 pkru)
 {
-	int err = 0;
-
-	if (use_xsave()) {
-		err = xsave_to_user_sigframe(buf);
-		if (!err)
-			err = update_pkru_in_sigframe(buf, pkru);
-		return err;
-	}
+	if (use_xsave())
+		return xsave_to_user_sigframe(buf, pkru);
 
 	if (use_fxsr())
 		return fxsave_to_user_sigframe((struct fxregs_state __user *) buf);

arch/x86/kernel/fpu/xstate.h

@@ -69,6 +69,16 @@ static inline u64 xfeatures_mask_independent(void)
 	return fpu_kernel_cfg.independent_features;
 }
 
+/*
+ * Update the value of PKRU register that was already pushed onto the signal frame.
+ */
+static inline int update_pkru_in_sigframe(struct xregs_state __user *buf, u32 pkru)
+{
+	if (unlikely(!cpu_feature_enabled(X86_FEATURE_OSPKE)))
+		return 0;
+	return __put_user(pkru, (unsigned int __user *)get_xsave_addr_user(buf, XFEATURE_PKRU));
+}
+
 /* XSAVE/XRSTOR wrapper functions */
 
 #ifdef CONFIG_X86_64
@@ -256,7 +266,7 @@ static inline u64 xfeatures_need_sigframe_write(void)
  * The caller has to zero buf::header before calling this because XSAVE*
  * does not touch the reserved fields in the header.
  */
-static inline int xsave_to_user_sigframe(struct xregs_state __user *buf)
+static inline int xsave_to_user_sigframe(struct xregs_state __user *buf, u32 pkru)
 {
 	/*
 	 * Include the features which are not xsaved/rstored by the kernel
@@ -281,6 +291,9 @@ static inline int xsave_to_user_sigframe(struct xregs_state __user *buf)
 	XSTATE_OP(XSAVE, buf, lmask, hmask, err);
 	clac();
 
+	if (!err)
+		err = update_pkru_in_sigframe(buf, pkru);
+
 	return err;
 }