lkml.org 
[lkml]   [2007]   [Jun]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH][ISDN] fix possible NULL deref on low memory condition in capidrv.c::send_message()
Date

If we fail to allocate an skb in
drivers/isdn/capi/capidrv.c::send_message(), then we'll end up
dereferencing a NULL pointer.
Since out of memory conditions are not unheard of, I believe it
is better to print a error message and just return rather than
bring down the whole kernel.
Sure, doing this may upset some application, but that's still
better than crashing the whole system.

(ps. please Cc me on replies from the isdn4linux list since I'm not subscribed
there)


Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
---

drivers/isdn/capi/capidrv.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/isdn/capi/capidrv.c b/drivers/isdn/capi/capidrv.c
index 23b6f7b..476012b 100644
--- a/drivers/isdn/capi/capidrv.c
+++ b/drivers/isdn/capi/capidrv.c
@@ -506,9 +506,14 @@ static void send_message(capidrv_contr * card, _cmsg * cmsg)
{
struct sk_buff *skb;
size_t len;
+
capi_cmsg2message(cmsg, cmsg->buf);
len = CAPIMSG_LEN(cmsg->buf);
skb = alloc_skb(len, GFP_ATOMIC);
+ if (!skb) {
+ printk(KERN_ERR "capidrv::send_message: can't allocate mem\n");
+ return;
+ }
memcpy(skb_put(skb, len), cmsg->buf, len);
if (capi20_put_message(&global.ap, skb) != CAPI_NOERROR)
kfree_skb(skb);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2007-06-25 01:11    [W:0.891 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site