2011-01-05 01:43:59

by Lukáš Turek

Subject: [PATCH] Bluetooth: Never deallocate a session when some DLC points to it

Fix a bug introduced in commit 9cf5b0ea3a7f1432c61029f7aaf4b8b338628884:
function rfcomm_recv_ua calls rfcomm_session_put without checking that
the session is not referenced by some DLC. If the session is freed, that
DLC would refer to deallocated memory, causing an oops later, as shown
in this bug report: https://bugzilla.kernel.org/show_bug.cgi?id=15994

Signed-off-by: Lukas Turek <[email protected]>
---
net/bluetooth/rfcomm/core.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index 432a9a6..cbe72c5 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -1164,7 +1164,8 @@ static int rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci)
* initiator rfcomm_process_rx already calls
* rfcomm_session_put() */
if (s->sock->sk->sk_state != BT_CLOSED)
- rfcomm_session_put(s);
+ if (list_empty(&s->dlcs))
+ rfcomm_session_put(s);
break;
}
}
--
1.7.2.2

2011-01-19 01:11:04

by Gustavo Padovan

Subject: Re: [PATCH] Bluetooth: Never deallocate a session when some DLC points to it

Hi Lukáš,

* Lukáš Turek <[email protected]> [2011-01-05 02:43:59 +0100]:

> Fix a bug introduced in commit 9cf5b0ea3a7f1432c61029f7aaf4b8b338628884:
> function rfcomm_recv_ua calls rfcomm_session_put without checking that
> the session is not referenced by some DLC. If the session is freed, that
> DLC would refer to deallocated memory, causing an oops later, as shown
> in this bug report: https://bugzilla.kernel.org/show_bug.cgi?id=15994
>
> Signed-off-by: Lukas Turek <[email protected]>
> ---
> net/bluetooth/rfcomm/core.c | 3 ++-
> 1 files changed, 2 insertions(+), 1 deletions(-)

Patch has been applied. Thanks.

--
Gustavo F. Padovan
http://profusion.mobi