KEYS: 64-bit MIPS needs to use compat_sys_keyctl for 32-bit userspace

MIPS64 needs to use compat_sys_keyctl for 32-bit userspace rather than
calling sys_keyctl.  The latter will work in a lot of cases, thereby hiding
the issue.
Reported-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: keyrings@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13832/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/scall64-n32.S

@@ -348,7 +348,7 @@ EXPORT(sysn32_call_table)
 	PTR	sys_ni_syscall			/* available, was setaltroot */
 	PTR	sys_add_key
 	PTR	sys_request_key
-	PTR	sys_keyctl			/* 6245 */
+	PTR	compat_sys_keyctl		/* 6245 */
 	PTR	sys_set_thread_area
 	PTR	sys_inotify_init
 	PTR	sys_inotify_add_watch

arch/mips/kernel/scall64-o32.S

@@ -504,7 +504,7 @@ EXPORT(sys32_call_table)
 	PTR	sys_ni_syscall			/* available, was setaltroot */
 	PTR	sys_add_key			/* 4280 */
 	PTR	sys_request_key
-	PTR	sys_keyctl
+	PTR	compat_sys_keyctl
 	PTR	sys_set_thread_area
 	PTR	sys_inotify_init
 	PTR	sys_inotify_add_watch		/* 4285 */