From: Helge Deller <deller@gmx.de>
Date: Fri, 12 Jan 2018 21:57:15 +0000 (+0100)
Subject: parisc: Hide virtual kernel memory layout
X-Git-Tag: v4.16-rc4~13^2~3
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=fd8d0ca2563151204f3fe555dc8ca4bcfe8677a3;p=users%2Fdwmw2%2Flinux.git

parisc: Hide virtual kernel memory layout

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>
---

diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 48f41399fc0b8..cab32ee824d2a 100644
--- 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"