lkml.org 
[lkml]   [2009]   [Feb]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch 15/33] Fix memory corruption in console selection
2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Mikulas Patocka <mpatocka@redhat.com>

commit 878b8619f711280fd05845e21956434b5e588cc4 upstream.

Fix an off-by-two memory error in console selection.

The loop below goes from sel_start to sel_end (inclusive), so it writes
one more character. This one more character was added to the allocated
size (+1), but it was not multiplied by an UTF-8 multiplier.

This patch fixes a memory corruption when UTF-8 console is used and the
user selects a few characters, all of them 3-byte in UTF-8 (for example
a frame line).

When memory redzones are enabled, a redzone corruption is reported.
When they are not enabled, trashing of random memory occurs.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/char/selection.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/char/selection.c
+++ b/drivers/char/selection.c
@@ -268,7 +268,7 @@ int set_selection(const struct tiocl_sel

/* Allocate a new buffer before freeing the old one ... */
multiplier = use_unicode ? 3 : 1; /* chars can take up to 3 bytes */
- bp = kmalloc((sel_end-sel_start)/2*multiplier+1, GFP_KERNEL);
+ bp = kmalloc(((sel_end-sel_start)/2+1)*multiplier, GFP_KERNEL);
if (!bp) {
printk(KERN_WARNING "selection: kmalloc() failed\n");
clear_selection();


\
 
 \ /
  Last update: 2009-02-04 19:47    [W:0.206 / U:0.356 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site