There is a use after released.transfer->req_id different obex->pending_req->id,See the following log, The packages is removd in cancel_complete func are not the same package in req_timeout func, but transfer pointer is released. log: g_obex_cancel_req() transfer->req_id 23 id 22 obex->pending_req(0x55b642c3e100) g_obex_cancel_req() match->data (0x55b642c344a0) g_obex_ref() ref 4 cancel_complete() pending req timeout 176 id 22 obex(0x55b642c3e100) transfer_response() obex 0x55b642c36480 transfer(0x55b642c3d000) g_obex_drop_tx_queue() g_obex_unref() obex 0x55b642c36480 g_obex_unref() ref 3 transfer_free() obex 0x55b642c36480 transfer 0x55b642c3d000 g_obex_unref() obex 0x55b642c36480 g_obex_unref() ref 2 pending_pkt_free() timeout_id 0 pending_pkt (0x55b642c344a0) step: [obex]# connect 28:33:34:1E:96:98 Attempting to connect to 28:33:34:1E:96:98 [NEW] Session /org/bluez/obex/client/session2 [default] [NEW] ObjectPush /org/bluez/obex/client/session2 Connection successful [28:33:34:1E:96:98]# send /home/uos/Desktop/systemd.zip Attempting to send /home/uos/Desktop/systemd.zip [NEW] Transfer /org/bluez/obex/client/session2/transfer2 Transfer /org/bluez/obex/client/session2/transfer2 Status: queued Name: systemd.zip Size: 33466053 Filename: /home/uos/Desktop/systemd.zip Session: /org/bluez/obex/client/session2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 [CHG] Transfer /org/bluez/obex/client/session2/transfer2 er2 33:34:1E:96:98]# cancel /org/bluez/obex/client/sessi Attempting to cancel transfer /org/bluez/obex/client/s Cancel successful valgrind trace: ==11431== Invalid read of size 4 ==11431== at 0x12B442: transfer_response () ==11431== by 0x127764: req_timeout () ==11431== by 0x49B8922: ??? ( ) ==11431== by 0x49B7E97: g_main_context_dispatch () ==11431== by 0x49B8287: ??? (in ) ==11431== by 0x49B8581: g_main_loop_run () ==11431== by 0x121834: main (main.c:322) ==11431== Address 0x7344fa0 is 16 bytes inside a block of size ==11431== at 0x48369AB: free () ==11431== by 0x12B459: transfer_response () ==11431== by 0x127B3D: cancel_complete () ==11431== by 0x49B7E97: g_main_context_dispatch () ==11431== by 0x49B8287: ??? () ==11431== by 0x49B8581: g_main_loop_run () ==11431== by 0x121834: main (main.c:322) ==11431== Block was alloc'd at ==11431== at 0x4837B65: calloc () ==11431== by 0x49BD9D8: g_malloc0 () ==11431== by 0x12AB89: transfer_new () ==11431== by 0x12B732: g_obex_put_req_pkt () ==11431== by 0x12B732: g_obex_put_req_pkt () ==11431== by 0x146982: transfer_start_put () ==11431== by 0x146982: obc_transfer_start () ==11431== by 0x13C5A7: session_process_transfer () ==11431== by 0x13D248: session_process_queue () ==11431== by 0x13D248: session_process_queue () ==11431== by 0x13D2AF: session_process () ==11431== by 0x49B7E97: g_main_context_dispatch () ==11431== by 0x49B8287: ??? (i) ==11431== by 0x49B8581: g_main_loop_run () ==11431== by 0x121834: main () ==11431== ==11431== (action on error) vgdb me ... --- gobex/gobex-transfer.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/gobex/gobex-transfer.c b/gobex/gobex-transfer.c index c94d018b2..03af4a14b 100644 --- a/gobex/gobex-transfer.c +++ b/gobex/gobex-transfer.c @@ -186,6 +186,9 @@ static void transfer_response(GObex *obex, GError *err, GObexPacket *rsp, gboolean rspcode, final; guint id; + if (!g_slist_find(transfers, transfer)) + return; + g_obex_debug(G_OBEX_DEBUG_TRANSFER, "transfer %u", transfer->id); id = transfer->req_id; -- 2.20.1