diff --git a/fs/proc/base.c b/fs/proc/base.c
index 82da55b5cffef804f4528bf1bed4d94645f7df2d..26a8f8416b79895af81b2af3a202ddc3dc17b020 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -86,7 +86,7 @@
 
 
 /* Worst case buffer size needed for holding an integer. */
-#define PROC_NUMBUF 10
+#define PROC_NUMBUF 13
 
 struct pid_entry {
 	int len;