iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Bluetooth: call sock_hold earlier in sco_conn_del

Browse Source 
In sco_conn_del, conn->sk is read while holding on to the
sco_conn.lock to avoid races with a socket that could be released
concurrently.

However, in between unlocking sco_conn.lock and calling sock_hold,
it's possible for the socket to be freed, which would cause a
use-after-free write when sock_hold is finally called.

To fix this, the reference count of the socket should be increased
while the sco_conn.lock is still held.

Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This commit is contained in:
Desmond Cheong Zhi Xi 2021-09-02 23:13:05 -04:00 committed by Luiz Augusto von Dentz
parent 15957cab9d
commit f4712fa993
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
net/bluetooth/sco.c
View File

@ -187,10 +187,11 @@ static void sco_conn_del(struct hci_conn *hcon, int err)
/* Kill socket */
sco_conn_lock(conn);
sk = conn->sk;
if (sk)
sock_hold(sk);
sco_conn_unlock(conn);
if (sk) {
sock_hold(sk);
lock_sock(sk);
sco_sock_clear_timer(sk);
sco_chan_del(sk, err);