[bluez/bluez] e5587b: gatt-client: avoid UAF after acquire notify failure

[bluez/bluez] e5587b: gatt-client: avoid UAF after acquire notify failure

[Andreas Kemnade]

  Branch: refs/heads/977363
  Home:   https://github.com/bluez/bluez
  Commit: e5587bcca145237768022617c458dabb564d563e
      https://github.com/bluez/bluez/commit/e5587bcca145237768022617c458dabb564d563e
  Author: Andreas Kemnade <andreas@kemnade.info>
  Date:   2025-06-30 (Mon, 30 Jun 2025)

  Changed paths:
    M src/gatt-client.c

  Log Message:
  -----------
  gatt-client: avoid UAF after acquire notify failure

If a disconnect happens during AcquireNotify dbus calls, a lot of
debris is left over. Subsequent calls to AcquireNotify will return
NotPermitted and StopNotify leads to an UAF, crashing bluetoothd.

Fix that by also clean up the socket stuff on failure.

This was provoked by putting the device into some RF shielding bag
and open and close it quickly.

Valgrind output:

bluetoothd[26032]: [:1.126:method_call] > org.bluez.GattCharacteristic1.AcquireNotify [#145]
bluetoothd[26032]: [:1.126:error] < org.bluez.Error.NotPermitted [#145]
bluetoothd[26032]: [:1.74:method_call] > org.freedesktop.DBus.Properties.GetAll [#895]
bluetoothd[26032]: [:1.74:method_return] < [#895]
bluetoothd[26032]: [:1.74:method_call] > org.bluez.GattCharacteristic1.StopNotify [#896]
==26032== Invalid read of size 8
==26032==    at 0x1A5721: notify_io_destroy (gatt-client.c:1562)
==26032==    by 0x1A7290: sock_io_destroy (gatt-client.c:1171)
==26032==    by 0x1A7290: destroy_sock (gatt-client.c:1192)
==26032==    by 0x1A73D6: characteristic_stop_notify (gatt-client.c:1698)
==26032==    by 0x1CF478: process_message (object.c:293)
==26032==    by 0x49CB71B: ??? (in /usr/lib/x86_64-linux-gnu/libdbus-1.so.3.32.4)
==26032==    by 0x49BB62A: dbus_connection_dispatch (in /usr/lib/x86_64-linux-gnu/libdbus-1.so.3.32.4)
==26032==    by 0x1CBCEF: message_dispatch (mainloop.c:59)
==26032==    by 0x48BF61E: g_main_context_dispatch (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)
==26032==    by 0x48BF9D7: ??? (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)
==26032==    by 0x48BFC8E: g_main_loop_run (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)
==26032==    by 0x202114: mainloop_run (mainloop-glib.c:65)
==26032==    by 0x202501: mainloop_run_with_signal (mainloop-notify.c:196)
==26032==  Address 0x5a7a430 is 0 bytes inside a block of size 32 free'd
==26032==    at 0x484417B: free (vg_replace_malloc.c:872)
==26032==    by 0x1DEC0F: complete_notify_request (gatt-client.c:1663)
==26032==    by 0x1DEC0F: enable_ccc_callback (gatt-client.c:1735)
==26032==    by 0x1DB8FF: disc_att_send_op (att.c:464)
==26032==    by 0x1DB8FF: disconnect_cb (att.c:676)
==26032==    by 0x2017A4: watch_callback (io-glib.c:173)
==26032==    by 0x48BF61E: g_main_context_dispatch (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)
==26032==    by 0x48BF9D7: ??? (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)
==26032==    by 0x48BFC8E: g_main_loop_run (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)
==26032==    by 0x202114: mainloop_run (mainloop-glib.c:65)
==26032==    by 0x202501: mainloop_run_with_signal (mainloop-notify.c:196)
==26032==    by 0x12E60C: main (main.c:1535)
==26032==  Block was alloc'd at
==26032==    at 0x48417B4: malloc (vg_replace_malloc.c:381)
==26032==    by 0x1D2F4D: util_malloc (util.c:46)
==26032==    by 0x1A5DD3: notify_client_create (gatt-client.c:1426)
==26032==    by 0x1A5EFC: characteristic_acquire_notify (gatt-client.c:1588)
==26032==    by 0x1CF478: process_message (object.c:293)
==26032==    by 0x49CB71B: ??? (in /usr/lib/x86_64-linux-gnu/libdbus-1.so.3.32.4)
==26032==    by 0x49BB62A: dbus_connection_dispatch (in /usr/lib/x86_64-linux-gnu/libdbus-1.so.3.32.4)
==26032==    by 0x1CBCEF: message_dispatch (mainloop.c:59)
==26032==    by 0x48BF61E: g_main_context_dispatch (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)
==26032==    by 0x48BF9D7: ??? (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7400.6)



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