Merge branch into tip/master: 'x86/shstk'

 # New commits in x86/shstk:
    2883f01ec37d ("x86/shstk: Enable shadow stacks for x32")

Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 7e8d46f..cc78226 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -374,7 +374,7 @@
 450	common	set_mempolicy_home_node	sys_set_mempolicy_home_node
 451	common	cachestat		sys_cachestat
 452	common	fchmodat2		sys_fchmodat2
-453	64	map_shadow_stack	sys_map_shadow_stack
+453	common	map_shadow_stack	sys_map_shadow_stack
 454	common	futex_wake		sys_futex_wake
 455	common	futex_wait		sys_futex_wait
 456	common	futex_requeue		sys_futex_requeue
diff --git a/arch/x86/kernel/shstk.c b/arch/x86/kernel/shstk.c
index 59e15dd..6f1e988 100644
--- a/arch/x86/kernel/shstk.c
+++ b/arch/x86/kernel/shstk.c
@@ -163,8 +163,8 @@
 	if (features_enabled(ARCH_SHSTK_SHSTK))
 		return 0;
 
-	/* Also not supported for 32 bit and x32 */
-	if (!cpu_feature_enabled(X86_FEATURE_USER_SHSTK) || in_32bit_syscall())
+	/* Also not supported for 32 bit */
+	if (!cpu_feature_enabled(X86_FEATURE_USER_SHSTK) || in_ia32_syscall())
 		return -EOPNOTSUPP;
 
 	size = adjust_shstk_size(0);
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index 23d8aaf..8a94053 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -315,6 +315,9 @@
 
 	uc_flags = frame_uc_flags(regs);
 
+	if (setup_signal_shadow_stack(ksig))
+		return -EFAULT;
+
 	if (!user_access_begin(frame, sizeof(*frame)))
 		return -EFAULT;
 
@@ -377,6 +380,9 @@
 	if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags))
 		goto badframe;
 
+	if (restore_signal_shadow_stack())
+		goto badframe;
+
 	if (compat_restore_altstack(&frame->uc.uc_stack))
 		goto badframe;