[PATCH] Bluetooth: sco: prevent information leak in sco_conn_defer_accept()

[PATCH] Bluetooth: sco: prevent information leak in sco_conn_defer_accept()

[Dan Carpenter]

Smatch complains that some of these struct members are not initialized
leading to a stack information disclosure:

    net/bluetooth/sco.c:778 sco_conn_defer_accept() warn:
    check that 'cp.retrans_effort' doesn't leak information

This seems like a valid warning.  I've added a default case to fix
this issue.  It's sort of unusual to have case SCO_AIRMODE_CVSD,
followed by a default case but I think it's nicely readable.  :)

Fixes: 2f69a82acf6f ("Bluetooth: Use voice setting in deferred SCO connection request")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 net/bluetooth/sco.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index d9a4e88dacbb..e2ee00fea64b 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -770,6 +770,7 @@ static void sco_conn_defer_accept(struct hci_conn *conn, u16 setting)
 			cp.retrans_effort = 0x02;
 			break;
 		case SCO_AIRMODE_CVSD:
+		default:
 			cp.max_latency = cpu_to_le16(0xffff);
 			cp.retrans_effort = 0xff;
 			break;
-- 
2.30.2

Re: [PATCH] Bluetooth: sco: prevent information leak in sco_conn_defer_accept()

[Marcel Holtmann]

Hi Dan,

> Smatch complains that some of these struct members are not initialized
> leading to a stack information disclosure:
> 
>    net/bluetooth/sco.c:778 sco_conn_defer_accept() warn:
>    check that 'cp.retrans_effort' doesn't leak information
> 
> This seems like a valid warning.  I've added a default case to fix
> this issue.  It's sort of unusual to have case SCO_AIRMODE_CVSD,
> followed by a default case but I think it's nicely readable.  :)
> 
> Fixes: 2f69a82acf6f ("Bluetooth: Use voice setting in deferred SCO connection request")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> net/bluetooth/sco.c | 1 +
> 1 file changed, 1 insertion(+)

I actually prefer a separate default statement since otherwise I get confused. Your patch with that minor change has been applied to bluetooth-next tree.

Regards

Marcel