[3.13.y.z extended stable] Patch "sh: fix format string bug in stack tracer" has been added to staging queue

Kamal Mostafa kamal at canonical.com
Thu May 1 19:17:36 UTC 2014

This is a note to let you know that I have just added a patch titled

    sh: fix format string bug in stack tracer

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:


This patch is scheduled to be released in version

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see



>From 7ca07be2d3594646675745d75eda159dc05ba057 Mon Sep 17 00:00:00 2001
From: Matt Fleming <matt.fleming at intel.com>
Date: Thu, 3 Apr 2014 14:46:20 -0700
Subject: sh: fix format string bug in stack tracer

commit a0c32761e73c9999cbf592b702f284221fea8040 upstream.

Kees reported the following error:

   arch/sh/kernel/dumpstack.c: In function 'print_trace_address':
   arch/sh/kernel/dumpstack.c:118:2: error: format not a string literal and no format arguments [-Werror=format-security]

Use the "%s" format so that it's impossible to interpret 'data' as a
format string.

Signed-off-by: Matt Fleming <matt.fleming at intel.com>
Reported-by: Kees Cook <keescook at chromium.org>
Acked-by: Kees Cook <keescook at chromium.org>
Cc: Paul Mundt <lethal at linux-sh.org>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
 arch/sh/kernel/dumpstack.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/sh/kernel/dumpstack.c b/arch/sh/kernel/dumpstack.c
index b959f55..8dfe645 100644
--- a/arch/sh/kernel/dumpstack.c
+++ b/arch/sh/kernel/dumpstack.c
@@ -115,7 +115,7 @@ static int print_trace_stack(void *data, char *name)
 static void print_trace_address(void *data, unsigned long addr, int reliable)
-	printk(data);
+	printk("%s", (char *)data);
 	printk_address(addr, reliable);


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