Bluetooth: L2CAP: Fix l2cap_global_chan_by_psm regression

commit 332f1795ca202489c665a75e62e18ff6284de077 upstream.

The patch d0be8347c623: "Bluetooth: L2CAP: Fix use-after-free caused
by l2cap_chan_put" from Jul 21, 2022, leads to the following Smatch
static checker warning:

        net/bluetooth/l2cap_core.c:1977 l2cap_global_chan_by_psm()
        error: we previously assumed 'c' could be null (see line 1996)

Fixes: d0be8347c623 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Luiz Augusto von Dentz 2022-08-01 13:52:07 -07:00 committed by Greg Kroah-Hartman
parent 4d5e45fdf0
commit 13e17a18a4

View File

@ -1813,11 +1813,11 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
bdaddr_t *dst,
u8 link_type)
{
struct l2cap_chan *c, *c1 = NULL;
struct l2cap_chan *c, *tmp, *c1 = NULL;
read_lock(&chan_list_lock);
list_for_each_entry(c, &chan_list, global_l) {
list_for_each_entry_safe(c, tmp, &chan_list, global_l) {
if (state && c->state != state)
continue;
@ -1836,11 +1836,10 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
dst_match = !bacmp(&c->dst, dst);
if (src_match && dst_match) {
c = l2cap_chan_hold_unless_zero(c);
if (!c)
continue;
read_unlock(&chan_list_lock);
return c;
if (c) {
read_unlock(&chan_list_lock);
return c;
}
}
/* Closest match */