lkml.org 
[lkml]   [2012]   [Mar]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[34-longterm 022/196] irda: prevent heap corruption on invalid nickname
Date
From: Dan Rosenberg <drosenberg@vsecurity.com>

-------------------
This is a commit scheduled for the next v2.6.34 longterm release.
If you see a problem with using this for longterm, please comment.
-------------------

commit d50e7e3604778bfc2dc40f440e0742dbae399d54 upstream.

Invalid nicknames containing only spaces will result in an underflow in
a memcpy size calculation, subsequently destroying the heap and
panicking.

v2 also catches the case where the provided nickname is longer than the
buffer size, which can result in controllable heap corruption.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
net/irda/irnet/irnet_ppp.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/net/irda/irnet/irnet_ppp.c b/net/irda/irnet/irnet_ppp.c
index 6a1a202..ab5bee2 100644
--- a/net/irda/irnet/irnet_ppp.c
+++ b/net/irda/irnet/irnet_ppp.c
@@ -106,6 +106,9 @@ irnet_ctrl_write(irnet_socket * ap,
while(isspace(start[length - 1]))
length--;

+ DABORT(length < 5 || length > NICKNAME_MAX_LEN + 5,
+ -EINVAL, CTRL_ERROR, "Invalid nickname.\n");
+
/* Copy the name for later reuse */
memcpy(ap->rname, start + 5, length - 5);
ap->rname[length - 5] = '\0';
--
1.7.9.3


\
 
 \ /
  Last update: 2012-03-13 02:07    [W:0.563 / U:0.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site