From e14037466b01cc83dca3453f7c812b9407237ce7 Mon Sep 17 00:00:00 2001 From: Denis Grigorev Date: Tue, 30 Jun 2020 16:47:31 +0300 Subject: [PATCH] gobex: Fix segfault caused by interrupted transfer When a obex transfer is interrupted by a peer in the middle, the response G_OBEX_RSP_FORBIDDEN comes and the transfer is freed in transfer_complete. However gobex is still ref'ed and gobex->io continues to be writable, so write_data() and then g_obex_abort() are called. When the abort response comes, struct obc_transfer is already freed, which leads to the crash. Backtrace : __GI___pthread_mutex_lock (mutex=0x65732f74) at pthread_mutex_lock.c:67 0xecc6eeda in dbus_connection_get_object_path_data () from libdbus-1.so.3 0x000457d4 in g_dbus_emit_property_changed_full () at gdbus/object.c:1794 0x00045868 in g_dbus_emit_property_changed () at gdbus/object.c:1832 0x000367f0 in transfer_set_status () at obexd/client/transfer.c:211 0x0003681e in transfer_set_status () at obexd/client/transfer.c:206 xfer_complete () at obexd/client/transfer.c:672 0x00022df6 in transfer_complete () at gobex/gobex-transfer.c:103 0x00022f44 in transfer_abort_response () at gobex/gobex-transfer.c:124 0x00020a0e in handle_response () at gobex/gobex.c:1128 0x00020dde in incoming_data () at gobex/gobex.c:1373 This commit introduces g_obex_drop_tx_queue(), which will be called if a transfer error detected. After the tx queue is dropped, obex shuts down gracefully. Signed-off-by: Anuj Jain Signed-off-by: Ayush Garg --- gobex/gobex-transfer.c | 5 +++++ gobex/gobex.c | 10 ++++++++++ gobex/gobex.h | 1 + 3 files changed, 16 insertions(+) diff --git a/gobex/gobex-transfer.c b/gobex/gobex-transfer.c index bc99306..e96e61f 100755 --- a/gobex/gobex-transfer.c +++ b/gobex/gobex-transfer.c @@ -100,6 +100,11 @@ static void transfer_complete(struct transfer *transfer, GError *err) g_obex_debug(G_OBEX_DEBUG_TRANSFER, "transfer %u", id); + if (err) { + /* No further tx must be performed */ + g_obex_drop_tx_queue(transfer->obex); + } + transfer->complete_func(transfer->obex, err, transfer->user_data); /* Check if the complete_func removed the transfer */ if (find_transfer(id) == NULL) diff --git a/gobex/gobex.c b/gobex/gobex.c index 6229128..23b300e 100644 --- a/gobex/gobex.c +++ b/gobex/gobex.c @@ -521,6 +521,16 @@ static void enable_tx(GObex *obex) obex->write_source = g_io_add_watch(obex->io, cond, write_data, obex); } +void g_obex_drop_tx_queue(GObex *obex) +{ + struct pending_pkt *p; + + g_obex_debug(G_OBEX_DEBUG_COMMAND, ""); + + while ((p = g_queue_pop_head(obex->tx_queue))) + pending_pkt_free(p); +} + static gboolean g_obex_send_internal(GObex *obex, struct pending_pkt *p, GError **err) { diff --git a/gobex/gobex.h b/gobex/gobex.h index a33fc60..a3282ef 100644 --- a/gobex/gobex.h +++ b/gobex/gobex.h @@ -63,6 +63,7 @@ gboolean g_obex_remove_request_function(GObex *obex, guint id); void g_obex_suspend(GObex *obex); void g_obex_resume(GObex *obex); gboolean g_obex_srm_active(GObex *obex); +void g_obex_drop_tx_queue(GObex *obex); GObex *g_obex_new(GIOChannel *io, GObexTransportType transport_type, gssize rx_mtu, gssize tx_mtu); -- 2.7.4