1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 3f96a6374e4f..7d34105e20c6 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -464,6 +464,12 @@ int __save_altstack(stack_t __user *, unsigned long);
 	unsafe_put_user(t->sas_ss_size, &__uss->ss_size, label); \
 } while (0);
 
+#ifdef CONFIG_DYNAMIC_SIGFRAME
+bool sigaltstack_size_valid(size_t ss_size);
+#else
+static inline bool sigaltstack_size_valid(size_t size) { return true; }
+#endif /* !CONFIG_DYNAMIC_SIGFRAME */
+
 #ifdef CONFIG_PROC_FS
 struct seq_file;
 extern void render_sigset_t(struct seq_file *, const char *, sigset_t *);