message: Fix assertion failure unpacking handle to an out-of-range fd

In the D-Bus wire protocol, the representation of a Unix fd is a simple
integer in the message body (referred to as the "handle" in GDBus)
which acts as an index into the array of out-of-band fds attached to
the message. The libdbus API (and therefore the dbus-python API)
automatically translates handles into fds, but the GDBus API does not,
making it possible for a GDBus sender to send a message containing
handles that are out-of-range for the number of attached fds. The
message bus also does not prevent such messages from being sent.

dbus-python services need to cope with this and fail gracefully while
unpacking the message, rather than crashing with an assertion failure
in UnixFd_tp_new when the fd turns out to be invalid.

Resolves: https://github.com/firewalld/firewalld/issues/985
Signed-off-by: Simon McVittie <smcv@collabora.com>

0 files changed, 0 insertions, 0 deletions