scan-build thinks that it’s possible for `read_netlink_messages()` to
return `FALSE` and an unset error (or `TRUE` and a set error), and this
belief causes it to emit warnings for code which calls
`read_netlink_messages()`.
That’s not possible, but the function is written in such a way that
following the control flow would be hard for a static analyser. It would
have to work out that `retval` and `local_error == NULL` are identical
on all control flow branches.
Avoid the need for such complex analysis by eliminating `retval` and
just using `local_error` throughout.
This introduces no functional changes to the code.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Helps: #1767
Add SPDX license (but not copyright) headers to all files which follow a
certain pattern in their existing non-machine-readable header comment.
This commit was entirely generated using the command:
```
git ls-files gio/*.[ch] | xargs perl -0777 -pi -e 's/\n \*\n \* This library is free software; you can redistribute it and\/or\n \* modify it under the terms of the GNU Lesser General Public/\n \*\n \* SPDX-License-Identifier: LGPL-2.1-or-later\n \*\n \* This library is free software; you can redistribute it and\/or\n \* modify it under the terms of the GNU Lesser General Public/igs'
```
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #1415
gio/gnetworkmonitornetlink.c: In function ‘remove_network’:
gio/gnetworkmonitornetlink.c:272:21: error: comparison of integer expressions of different signedness: ‘int’ and ‘guint’ {aka ‘unsigned int’}
272 | for (i = 0; i < nl->priv->dump_networks->len; i++)
| ^
Currently this function calls `g_warning()` explicitly. It would be
nicer to properly propagate these failure up to the caller that tried to
initialise us.
`read_netlink_messages()` is the callback attached to the netlink socket
(G_IO_IN). It calls `g_socket_receive_message()`. There is a race
condition that if the socket is closed while there is a pending call, we
will try to receive on a closed socket, which fails.
To avoid this, we switch the order of the operations around: first
destroy the source and then close the socket.
This is not a correct way to check if `g_socket_new_from_fd()` failed.
Instead just see if it returned `NULL` itself.
This was preventing the netlink monitor from being initialised.
Closes#1518
When using g_network_monitor_get_default() from another thread, it’s
possible for network-changed events to be processed after an instance of
GNetworkMonitor has been disposed, causing use-after-free problems.
Fix that by moving some of the initialisation into the GInitable.init()
chain, rather than in a main context idle callback.
This includes a unit test which probabilistically reproduces the bug
(but can’t do so deterministically due to it being a race condition).
Commit amended by Philip Withnall <withnall@endlessm.com> before
pushing.
https://bugzilla.gnome.org/show_bug.cgi?id=793727
If the GNetworkMonitorNetlink is finalised part-way through a dump
(after request_dump() is called, but before finish_dump() is called),
dump_networks was leaked. Fix that.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
https://bugzilla.gnome.org/show_bug.cgi?id=793880
This should introduce no functional changes. Factor out some common
code, flip some arguments around to use the more conventional (data,
length) order, and move some memory management calls out of
if-blocks.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
https://bugzilla.gnome.org/show_bug.cgi?id=793880
By using g_timeout_source_new_seconds(), we can let timer wakeups be
coalesced by the scheduler, and reduce power consumption a bit. This
shouldn’t really affect the accuracy of the network monitoring.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
https://bugzilla.gnome.org/show_bug.cgi?id=793880
Previously, the GSource would be attached to whatever GMainContext was
the thread default at the time; but that might no longer be the same as
the default at the time of constructing the GNetworkMonitor.
Save the default from construction time, so that source callbacks are
always invoked in the same GMainContext.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
https://bugzilla.gnome.org/show_bug.cgi?id=793880
Prevent the situation where errno is set by function A, then function B
is called (which is typically _(), but could be anything else) and it
overwrites errno, then errno is checked by the caller.
errno is a horrific API, and we need to be careful to save its value as
soon as a function call (which might set it) returns. i.e. Follow the
pattern:
int errsv, ret;
ret = some_call_which_might_set_errno ();
errsv = errno;
if (ret < 0)
puts (strerror (errsv));
This patch implements that pattern throughout GLib. There might be a few
places in the test code which still use errno directly. They should be
ported as necessary. It doesn’t modify all the call sites like this:
if (some_call_which_might_set_errno () && errno == ESOMETHING)
since the refactoring involved is probably more harmful than beneficial
there. It does, however, refactor other call sites regardless of whether
they were originally buggy.
https://bugzilla.gnome.org/show_bug.cgi?id=785577
This code used to look at the SCM_CREDENTIALS and ignore every message
not from uid 0. However, when user namespaces are in use this does not
work, as if uid 0 is not mapped you get overflowuid instead. Right now
this means we ignore all messages in such user namespaces and glib
apps hang on startup.
We can't look at pids either, as pid 0 is returned for processes
outside your pid namespace.
Instead the correct approach is to look at the sending sockaddr and
if the port id (nl_pid) is zero, then its from the kernel.
Source:
http://lists.linuxfoundation.org/pipermail/containers/2015-May/036032.htmlhttps://bugzilla.gnome.org/show_bug.cgi?id=750203
For some reason, IPv6 link-local multicast routing changes all the
time. GNetworkMonitorBase was already ignoring them for purposes of
emitting network-changed, but GNetworkMonitorNetlink would still
trigger a re-dump after getting one, so network-changed would end up
getting emitted anyway.
If the default route is via a device rather than a particular IP
address, then neither RTA_DST nor RTA_GATEWAY will be present in the
RTM_NEWROUTE message, and so GNetworkMonitorNetlink would ignore it,
and then think there was no default route. (This could happen with
certain kinds of VPNs, if they were set to route all traffic through
the VPN.)
Fix this by recognizing routes that specify RTA_OIF ("output
interface") instead of RTA_GATEWAY.
https://bugzilla.gnome.org/show_bug.cgi?id=701609
As it turns out, we have examples of internal functions called
type_name_get_private() in the wild (especially among older libraries),
so we need to use a name for the per-instance private data getter
function that hopefully won't conflict with anything.
There are two benefits to this:
1) We can centralize any operating system specific knowledge of
close-vs-EINTR handling. For example, while on Linux we should never
retry, if someone cared enough later about HP-UX, they could come by
and change this one spot.
2) For places that do care about the return value and want to provide
the caller with a GError, this function makes it convenient to do so.
Note that gspawn.c had an incorrect EINTR loop-retry around close().
https://bugzilla.gnome.org/show_bug.cgi?id=682819
Use the same code GSocket does, to try SOCK_CLOEXEC first, and then
fall back to FD_CLOEXEC if it fails. (And fix that code to not call
fcntl if SOCK_CLOEXEC worked.)
https://bugzilla.gnome.org/show_bug.cgi?id=692332
Add g_socket_get_option() and g_socket_set_option(), wrapping
getsockopt/setsockopt for the case of integer-valued options. Update
code to use these instead of the underlying calls.
https://bugzilla.gnome.org/show_bug.cgi?id=623187
When trying to compile glib master on a RHEL 6.2 system, it fails with:
make[4]: Entering directory `/home/teuf/gnome/src/glib/gio'
CC libgio_2_0_la-gnetworkmonitornetlink.lo
In file included from gnetworkmonitornetlink.c:25:
/usr/include/linux/netlink.h:35: error: expected specifier-qualifier-list before 'sa_family_t'
gnetworkmonitornetlink.c: In function 'g_network_monitor_netlink_initable_init':
gnetworkmonitornetlink.c:99: error: 'struct sockaddr_nl' has no member named 'nl_family'
gnetworkmonitornetlink.c💯 error: 'struct sockaddr_nl' has no member named 'nl_pid'
gnetworkmonitornetlink.c💯 error: 'struct sockaddr_nl' has no member named 'nl_pad'
gnetworkmonitornetlink.c:101: error: 'struct sockaddr_nl' has no member named 'nl_groups'
make[4]: *** [libgio_2_0_la-gnetworkmonitornetlink.lo] Error 1
sa_family_t is defined in sys/socket.h, this commit makes sure this header is included before netlink.h
This fixes bgo bug #666001
Add GNetworkMonitor and its associated extension point, provide a base
implementation that always claims the network is available, and a
netlink-based implementation built on top of that that actually tracks
the network state.
https://bugzilla.gnome.org/show_bug.cgi?id=620932
