CID 59391 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW)
31. fixed_size_dest: You might overrun the 16-character fixed-size string be.ifspec.spec.ifname by copying priv->nas_ifname without checking the length.
get_word() only moves the "argument" pointer forward. It never sets it
to %NULL. Also, above we already dereference argument, so Coverity thinks
that this NULL check indicates a bug.
Drop it to silence Coverity.
Warned by coverity: we assert above that brfd is -1, so we must always
restore it to -1 in the error case.
Technically, not a problem because socket() is documented to return
only -1 on error already. Apparently coverity does not believe that.
nl80211_alloc_msg() just allocates some memory, using glib's allocators.
Hence it cannot fail, and we don't need to check for that.
Drop the unnecessary %NULL checks.
Usually we check the result of nla_nest_start(). Also, in most cases where this
function would return %NULL, it's an actual bug. That is, because our netlink
message is allocated with a large buffer, and in most cases we append there a well
known, small amount of data.
To make coverity happy, handle the case and assert.
This triggers a coverity warning because we above already
check that not all relevant keys are NULL together.
Work around warning by modifying the code.
- use nm_g_variant_unref_floating()
- rename _lldp_attr_take_str_ptr() to _lldp_attr_set_str_take().
The new name has the same "_lldp_attr_set_" prefix as other setters.
Also, with the previous name it is unclear why it takes a "str-ptr".
- setting the same attribute multiple times, ignores all but the first
value. Avoid cloning the string in that case, and explicitly choose
the set or take function.
Valgrind complains:
==26355== 32 bytes in 2 blocks are definitely lost in loss record 2,829 of 6,716
==26355== at 0x4838748: malloc (vg_replace_malloc.c:308)
==26355== by 0x483AD63: realloc (vg_replace_malloc.c:836)
==26355== by 0x4F6AD4F: g_realloc (in /usr/lib64/libglib-2.0.so.0.6000.6)
==26355== by 0x4F87B33: ??? (in /usr/lib64/libglib-2.0.so.0.6000.6)
==26355== by 0x4F87B96: g_string_sized_new (in /usr/lib64/libglib-2.0.so.0.6000.6)
==26355== by 0x2D66E1: nm_utils_buf_utf8safe_escape (nm-shared-utils.c:1911)
==26355== by 0x4113B0: lldp_neighbor_new (nm-lldp-listener.c:676)
==26355== by 0x412788: process_lldp_neighbor (nm-lldp-listener.c:882)
==26355== by 0x4135CF: lldp_event_handler (nm-lldp-listener.c:931)
==26355== by 0x422CDB: lldp_callback (sd-lldp.c:50)
==26355== by 0x4235F9: lldp_add_neighbor (sd-lldp.c:166)
==26355== by 0x423679: lldp_handle_datagram (sd-lldp.c:189)
==26355== by 0x423C8B: lldp_receive_datagram (sd-lldp.c:235)
==26355== by 0x2F887A: source_dispatch (sd-event.c:2832)
==26355== by 0x2FAD43: sd_event_dispatch (sd-event.c:3245)
==26355== by 0x2D9237: event_dispatch (nm-sd.c:51)
==26355== by 0x4F64EDC: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.6000.6)
==26355== by 0x4F6526F: ??? (in /usr/lib64/libglib-2.0.so.0.6000.6)
==26355== by 0x4F655A2: g_main_loop_run (in /usr/lib64/libglib-2.0.so.0.6000.6)
==26355== by 0x140932: main (main.c:465)
==26355==
Not all masters type have a platform link and so it's wrong to check
for it to decide whether the slave should be really released. Move the
check to master devices that need it (bond, bridge and team).
OVS ports don't need the check because they don't call to platform to
remove a slave.
https://bugzilla.redhat.com/show_bug.cgi?id=1733709
We set nm-owned to indicate whether a software device was created by
NM or it was pre-existing. When checking the existence, we must verify
also whether the link type is compatible with the device, otherwise it
is possible to match unrelated interfaces. For example, when checking
for the existence of an ovs-bridge (which is not compatible with any
platform link) we could match a unrelated platform link with the same
name.
https://bugzilla.redhat.com/show_bug.cgi?id=1733709
These are special -- initramfs configured them and killed dhclient. Bad
things would happen if we let the addresses expire though.
Let's act as if initramfs actually passed the configuration to us.
It actually tries to do so by the means of writing an ifcfg file, but
that one is too broken to be useful, so the ifcfg-rh plugin ignores it.
Notably, it doesn't have the actual addresses or correct BOOTPROTO.
The generated connection is better.
Co-authored-by: Thomas Haller <thaller@redhat.com>
With "wireguard.ip4-auto-default-route" and "wireguard.ip6-auto-default-route",
NetworkManager automatically adds policy routing rules for the default
route.
For that, it needs to pick (up to) two numbers:
- the fwmark. This is used both for WireGuard's fwmark setting and
is also the number of the routing table where the default-route is
added.
- the rule priority. NetworkManager adds two policy routing rules, and
we need to place them somewhere before the default rules (at 32766).
Previously, we looked at exiting platform configuration and picked
numbers that were not yet used. However, during restart of
NetworkManager, we leave the interface up and after restart we will
take over the previous configuration. At that point, we need to choose
the same fwmark/priority, otherwise the configuration changes.
But since we picked numbers that were not yet used, we would always choose
different numbers. For routing rules that meant that after restart a second
pair of rules was added.
We possibly could store this data in the device's state-file. But that
is complex. Instead, just pick numbers deterministically based on the
connection's UUID.
If the picked numbers are not suitable, then the user can still work
around that:
- for fwmark, the user can explicitly configure wireguard.fwmark
setting.
- for the policy routes, the user can explicitly add the rules with
the desired priorirites (arguably, currently the default-route cannot
be added like a regular route, so the table cannot be set. Possibly
the user would have to add two /1 routes instead with
suppress_prefixlength=1).
We call _auto_default_route_init() at various places, for example during
coerce_route_table(). We cannot be sure that we don't call it before
activation starts (before stage1) or after device-cleanup.
That means, upon activation, we need to clear the state first. Do that in
act_stage1_prepare().
#3 0x00007fb0aa9e7d3d in g_return_if_fail_warning
(log_domain=log_domain@entry=0x562295fd5ee3 "libnm", pretty_function=pretty_function@entry=0x562295fd71d0 <__func__.35180> "_connection_get_setting_check", expression=expression@entry=0x562295f8edf7 "NM_IS_CONNECTION (connection)") at ../glib/gmessages.c:2767
#4 0x0000562295df151a in _connection_get_setting_check (connection=0x0, setting_type=0x562297b17050 [NMSettingWireGuard/NMSetting]) at libnm-core/nm-connection.c:207
#5 0x0000562295df151a in _connection_get_setting_check (connection=0x0, setting_type=0x562297b17050 [NMSettingWireGuard/NMSetting]) at libnm-core/nm-connection.c:205
#6 0x0000562295ef132a in _nm_connection_get_setting (type=<optimized out>, connection=0x0) at ./libnm-core/nm-core-internal.h:483
#7 0x0000562295ef132a in _auto_default_route_init (self=self@entry=0x562297bf82b0 [NMDeviceWireGuard]) at src/devices/nm-device-wireguard.c:443
#8 0x0000562295ef1b98 in coerce_route_table (device=0x562297bf82b0 [NMDeviceWireGuard], addr_family=2, route_table=0, is_user_config=<optimized out>)
at src/devices/nm-device-wireguard.c:565
#9 0x0000562295ea42ae in _get_route_table (self=self@entry=0x562297bf82b0 [NMDeviceWireGuard], addr_family=addr_family@entry=2) at src/devices/nm-device.c:2311
#10 0x0000562295ea4593 in nm_device_get_route_table (self=0x562297bf82b0 [NMDeviceWireGuard], addr_family=2) at src/devices/nm-device.c:2338
#11 0x0000562295eabde0 in ip_config_merge_and_apply (self=0x562297bf82b0 [NMDeviceWireGuard], addr_family=2, commit=1) at src/devices/nm-device.c:7590
#12 0x0000562295ed2f0b in device_link_changed (self=self@entry=0x562297bf82b0 [NMDeviceWireGuard]) at src/devices/nm-device.c:3939
#13 0x00007fb0aa9dc7db in g_idle_dispatch (source=source@entry=0x562297bf0b30, callback=0x562295ed2880 <device_link_changed>, user_data=0x562297bf82b0) at ../glib/gmain.c:5627
#14 0x00007fb0aa9dfedd in g_main_dispatch (context=0x562297a28090) at ../glib/gmain.c:3189
#15 0x00007fb0aa9dfedd in g_main_context_dispatch (context=context@entry=0x562297a28090) at ../glib/gmain.c:3854
#16 0x00007fb0aa9e0270 in g_main_context_iterate (context=0x562297a28090, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:3927
#17 0x00007fb0aa9e05a3 in g_main_loop_run (loop=0x562297a0b380) at ../glib/gmain.c:4123
#18 0x0000562295d0b147 in main (argc=<optimized out>, argv=<optimized out>) at src/main.c:465
https://bugzilla.redhat.com/show_bug.cgi?id=1734383
For WireGuard (like for all IP-tunnels and IP-based VPNs), the IP addresses of
the peers must be reached outside the tunnel/VPN itself.
For VPN connections, NetworkManager usually adds a direct /32 route to
the external VPN gateway to the underlying device. For WireGuard that is
not done, because injecting a route to another device is ugly and error
prone. Worse: WireGuard with automatic roaming and multiple peers makes this
more complicated.
This is commonly a problem when setting the default-route via the VPN,
but there are also other subtle setups where special care must be taken
to prevent such routing loops.
WireGuard's wg-quick provides a simple, automatic solution by adding two policy
routing rules and relying on the WireGuard packets having a fwmark set (see [1]).
Let's also do that. Add new properties "wireguard.ip4-auto-default-route"
and "wireguard.ip6-auto-default-route" to enable/disable this. Note that
the default value lets NetworkManager automatically choose whether to
enable it (depending on whether there are any peers that have a default
route). This means, common scenarios should now work well without additional
configuration.
Note that this is also a change in behavior and upon package upgrade
NetworkManager may start adding policy routes (if there are peers that
have a default-route). This is a change in behavior, as the user already
clearly had this setup working and configured some working solution
already.
The new automatism picks the rule priority automatically and adds the
default-route to the routing table that has the same number as the fwmark.
If any of this is unsuitable, then the user is free to disable this
automatism. Note that since 1.18.0 NetworkManager supports policy routing (*).
That means, what this automatism does can be also achieved via explicit
configuration of the profile, which gives the user more flexibility to
adjust all parameters explicitly).
(*) but only since 1.20.0 NetworkManager supports the "suppress_prefixlength"
rule attribute, which makes it impossible to configure exactly this rule-based
solution with 1.18.0 NetworkManager.
[1] https://www.wireguard.com/netns/#improved-rule-based-routing
NMPlatformObject is a base-type of all actual platform structs.
We very seldomly use this type directly. Most callers that pass
the plobj to nmp_object_new() will need to cast it.
Make the varible a void pointer to not require the cast.
mesh connections can be started at any time but prevent a connection
using ip auto configuration to start, if no mesh point providing the
network is in range.
To allow completion for mesh connections channel and band need to be
set. This is only done if both values are absent. It does not check
existing values against a given ap_freq. This maybe changed to throw an
error and detect a possible conflict. Any other check is left to verify
step of connection.
This change allows to use ap freq during complete. For tests 0 is passed
as frequency for now. This needs to be changed if completion of freq
should be tested.
[lkundrak@v3.sk, thaller@redhat.com: formatting fixes]
mark ap if supplicant reports bss property "Mode = 'mesh'".
bss mode mesh is available since hostap_2_6-729-g213eb1885
check mesh connections are compatible with detected mode.
This ensures that we know whether wpa_supplicant was built with
CONFIG_MESH enabled.
[andreas.kling@peiker-cee.de: add add PROP_MESH_SUPPORT to
set_property()]
deactivate switches the device back to infrastructure mode for
compatibility reasons. This will prevent supplicant from de-assosiating
non-infrastructure connections as the interface goes down.
Disconnect asynchronously and wait for the result. This is required for
e.g. 802.11s mesh.
allow to call dbus method "Disconnect" and handle a callback given by
the caller. This allows graceful disconnects that require to wait for
the operation to complete.
Tombstones in /etc are not only to hide storages of type keyfile. They
are for hiding/shadowing any profile from persistant storage. That's
why we need to compare them already in _sett_conn_entry_sds_update().
Fix the prioriy of storages for the same UUID.
Note that the "$UUID.nmmeta" files (the tombstones) are handled by
keyfile plugin. But that is only to load them together during `nmcli
connection reload` when we iterate the files of the system-connections
directory. For the most part, nmmeta/tombstones are not keyfile specific
and handled by NMSettings. A tombstone in /run hides any profile (regardless
of the settings plugin). And a tombstones in /etc hides any profile, except
in-memory connections from keyfile /run directory.
Note that we now support keyfiles from read-only storage in /usr/lib.
Note also that we do support modifying and deleting these profiles.
That works by placing a shadowing profile to /etc or /run.
Surely this is questionable. It means that once the user uses D-Bus
to modify/delete a profile in /usr/lib, that profile becomes forever
shadowed by a different file, and there is no D-Bus API to return
to the original file. The user would have to drop the shadowing storages
from the file system. That is a problem.
But on the other hand, disallowing changes to such read-only profiles
is not very useful either. If you no longer can use D-Bus to modify such
profiles, what's the value here? How are applications supposed to handle
such profiles if there is no D-Bus API to do something sensible to them?
So, whatever problems read-only profiles and this shadowing causes, I don't
think that the solution is to entirely disallow changes via D-Bus.
At that point, we can just as well allow changes to profiles from
ifupdown. Note that you still cannot modify the profile directly (as the
ifupdown plugin does not support that). But you can delete the profile
(either temporarily via a tombstone in /run or permanently via a
tombstone in /etc). You also can make the profile in-memory, and take
it from there. Note that if you try to later store the in-memory profile
to disk again, then it depends on the order of settings plugins whether
that succeeds. If you have "plugins=keyfile,ifupdown", then the profile
will be stored as keyfile to /etc. If you have "plugins=ifupdown,keyfile",
then the modification will only be done in /run and the "to-disk" command
silently ignored (there really is no better solution).
First of all, the generated profile also gets generated as keyfile to
/run, thereby it looses the read-only flag (because this flag gets lost
when storing the profile to keyfile).
Second, I don't think we should artificially limit the capabilities
of the generated profile. If the user chooses to modify/delete it, so
just allow it.
Via Update2() D-Bus API there are three ways how a profile can be stored
(or migrated) to in-memory:
- NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY
- NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED
- NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_ONLY
With the recent rework of settings I dropped NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY
and it had the same meaning as NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED.
However, the way NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED was implemented is
problematic. The problem is that it leaves the profile on disk but creates an
in-memory representation which shadows the persistent storage. Later,
when storing the profile to disk again, a new filename is chosen.
This allows via D-Bus API to toggle between NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED
and NM_SETTINGS_UPDATE2_FLAG_TO_DISK, and thereby pilling up profiles on disk.
Also, there is no D-Bus API to do anything sensible with these leaked, shadowed
profiles on disk.
Note that if we have a read-only profile in /usr/lib or in ifupdown
plugin, then the problem is not made any worse. That is, because via D-Bus
API such profiles can be made in-memory, and afterwards stored to /etc.
Thereby too the profile gets duplicate on disk, but this game only
works once. Afterwards, you cannot repeat it to create additional
profiles on disk. It means, you can only leak profiles once, and only
if they already exist in read-only storage to begin with.
This problem with NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED already existed
before the settings-delegate-storage rework, and is unrelated to whether in-memory
profiles now happen to be persisted to /run.
Note that NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_ONLY is simple and does not suffer
from this problem. When you move a profile to in-memory-only, it gets deleted from
persistent storage and no duplication happens.
The problem is that NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED used to
forget about the profile that it shadows, and that is wrong.
So, first re-add proper support for NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY. This
works by remembering the "shadowed-storage" path for in-memory profiles.
When later saving such a profile to disk again, the shadowed-storage
will be re-used. Likewise, when deleting such a profile, the shadowed
storage will be deleted.
Note that we keep NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED and it
also remembers the shadowed storage (but without "owning" it). That means,
when such a profile gets saved to disk again, the orginal storage is
reused too. As such, during future updates it behaves just like
NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY. The difference is when deleting
such a profile. In this case, the profile is left on storage and a
tombstone gets written. So, how is this better than before and why even
keep this complicated flag?
First, we keep this flag because we really want the ansible role to be
able to do in-memory changes only. That implies being able to delete a
profile from NetworkManager's view, but not from persistent storage. Without
this flag there is no way to do that. You can only modify an on-disk profile
by shadowing it, but you could not delete it form NetworkManager's view
while keeping it on disk.
The new form of NM_SETTINGS_UPDATE2_FLAG_IN_MEMORY_DETACHED is safe and avoids
the duplication problem because also for tombstones it remembers the original
"shadowed-storage". That is, when the profile gets recreated later via
D-Bus API AddConnection, then the re-created profile will still reference
and reuse the shadowed storage that it had before deletion.
Say, you configure "plugins=ifcfg-rh,keyfile" and have an ifcfg file for
a certain profile. Then you make it IN-MEMORY-DETACHED and delete it.
The result is that the ifcfg file still exists, but there is a tombstone
nmmeta file that shadows the profile.
Now, if you want to re-add the same profile (same UUID) and store it to
persistent storage, then first it will try to persist the profile via
the ifcfg-rh plugin. That may not be possible, for example because the
connection type is not supported by the plugin.
Now, you could write it to /etc as keyfile, but then there would still
be a higher priority profile. Note that after calling
_add_connection_to_first_plugin() we issue
_connection_changed_track (self, new_storage, new_connection, TRUE);
(note the prioritize=TRUE parameter). So, in the first moment, all looks
good. However it is not because upon first reload the change gets
reverted and the other profile resurfaces.
The problem are that all settings plugins (except keyfile) may be
completely unable to persist a profile. The real and only solution is
not to use any settings plugins except keyfile.
In a previous version (that never was merged), the "loaded-path" of nmmeta
files was used to prioritize profiles. Since that was not done, we
should not add profiles that we know have lower priority than existing
profiles.
