parisc: Hide virtual kernel memory layout

commit fd8d0ca2563151204f3fe555dc8ca4bcfe8677a3 upstream.

For security reasons do not expose the virtual kernel memory layout to
userspace.

Signed-off-by: Helge Deller <deller@gmx.de>
Suggested-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org # 4.15
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 48f41399fc0b8b63acd84d774a09ad2d0aba5086..cab32ee824d2ac4b7fe9adf4f3bb25533cc043c6 100644 (file)
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -629,7 +629,12 @@ void __init mem_init(void)
 #endif
 
        mem_init_print_info(NULL);
-#ifdef CONFIG_DEBUG_KERNEL /* double-sanity-check paranoia */
+
+#if 0
+       /*
+        * Do not expose the virtual kernel memory layout to userspace.
+        * But keep code for debugging purposes.
+        */
        printk("virtual kernel memory layout:\n"
               "    vmalloc : 0x%px - 0x%px   (%4ld MB)\n"
               "    memory  : 0x%px - 0x%px   (%4ld MB)\n"