From c2c77ec83bdad17fb688557b5b3fdc36661dd1c6 Mon Sep 17 00:00:00 2001 From: Andrei Emeltchenko Date: Fri, 19 Mar 2010 10:26:28 +0200 Subject: [PATCH] Bluetooth: Fix kernel crash on L2CAP stress tests Added very simple check that req buffer has enough space to fit configuration parameters. Shall be enough to reject packets with configuration size more than req buffer. Crash trace below [ 6069.659393] Unable to handle kernel paging request at virtual address 02000205 [ 6069.673034] Internal error: Oops: 805 [#1] PREEMPT ... [ 6069.727172] PC is at l2cap_add_conf_opt+0x70/0xf0 [l2cap] [ 6069.732604] LR is at l2cap_recv_frame+0x1350/0x2e78 [l2cap] ... [ 6070.030303] Backtrace: [ 6070.032806] [] (l2cap_add_conf_opt+0x0/0xf0 [l2cap]) from [] (l2cap_recv_frame+0x1350/0x2e78 [l2cap]) [ 6070.043823] r8:dc5d3100 r7:df2a91d6 r6:00000001 r5:df2a8000 r4:00000200 [ 6070.050659] [] (l2cap_recv_frame+0x0/0x2e78 [l2cap]) from [] (l2cap_recv_acldata+0x2bc/0x350 [l2cap]) [ 6070.061798] [] (l2cap_recv_acldata+0x0/0x350 [l2cap]) from [] (hci_rx_task+0x244/0x478 [bluetooth]) [ 6070.072631] r6:dc647700 r5:00000001 r4:df2ab740 [ 6070.077362] [] (hci_rx_task+0x0/0x478 [bluetooth]) from [] (tasklet_action+0x78/0xd8) [ 6070.087005] [] (tasklet_action+0x0/0xd8) from [] Signed-off-by: Andrei Emeltchenko Acked-by: Gustavo F. Padovan Signed-off-by: Marcel Holtmann --- net/bluetooth/l2cap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c index 43e17f7d7ecd..7794a2e2adce 100644 --- a/net/bluetooth/l2cap.c +++ b/net/bluetooth/l2cap.c @@ -2832,6 +2832,11 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr int len = cmd->len - sizeof(*rsp); char req[64]; + if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) { + l2cap_send_disconn_req(conn, sk); + goto done; + } + /* throw out any old stored conf requests */ result = L2CAP_CONF_SUCCESS; len = l2cap_parse_conf_rsp(sk, rsp->data, -- 2.39.5