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[PATCH] kernel: make /proc/kallsyms mode 400 to reduce ease of attacking

From:  Marcus Meissner <meissner-AT-suse.de>
To:  linux-kernel-AT-vger.kernel.org, jason.wessel-AT-windriver.com, fweisbec-AT-gmail.com, tj-AT-kernel.org, mort-AT-sgi.com, akpm-AT-osdl.org
Subject:  [PATCH] kernel: make /proc/kallsyms mode 400 to reduce ease of attacking
Date:  Thu, 4 Nov 2010 11:09:14 +0100
Message-ID:  <20101104100914.GC25118@suse.de>
Cc:  security-AT-kernel.org
Archive-link:  Article, Thread


Hi,

Making /proc/kallsyms readable only for root makes it harder
for attackers to write generic kernel exploits by removing
one source of knowledge where things are in the kernel.

Signed-off-by: Marcus Meissner <meissner@suse.de>
---
 kernel/kallsyms.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 6f6d091..a8db257 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -546,7 +546,7 @@ static const struct file_operations kallsyms_operations = {
 
 static int __init kallsyms_init(void)
 {
-	proc_create("kallsyms", 0444, NULL, &kallsyms_operations);
+	proc_create("kallsyms", 0400, NULL, &kallsyms_operations);
 	return 0;
 }
 device_initcall(kallsyms_init);
-- 
1.7.1



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