Background: when router sends router advertisement (RA) message,
NetworkManager processes it and passes data to a lower system layer.
Currently there is a problem that NetworkManager adds one second to both
valid lifetime and preferred lifetime. This happens because of the
algorithm in nm_ndisc_data_to_l3cd() function.
Let's look at an example: let current timestamp be 100450, so now_sec
variable is 100. At this moment RA message was received from the router.
The IPv6 address' valid lifetime is 200 seconds (for example), so
expiration timestamp (ndisc_addr->expiry_msec) is 300450. But after the
_nm_ndisc_lifetime_from_expiry() call, NMPlatformIP6Address lifetime
becomes 201 ((300450-(100*1000)+999)/1000). Which is wrong.
This commit fixes this behaviour by replacing
nm_utils_get_monotonic_timestamp_sec() with
nm_utils_get_monotonic_timestamp_msec() so that timestamps are
calculated more precisely.
Related issue: https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/1464
Merge request: https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1863
It's not clear in which circumstances, but 'type' can be NULL as in
the following backtrace:
nmc_connection_check_deprecated (c=c@entry=0x55d93f937610) at src/nmcli/connections.c:676
connection_warnings (nmc=nmc@entry=0x55d93f5ae5e0 <nm_cli>, connection=connection@entry=0x55d93f937610) at src/nmcli/connections.c:5464
add_connection_cb (client=<optimized out>, result=<optimized out>, user_data=0x55d93fc83820) at src/nmcli/connections.c:5510
g_task_return_now (task=0x55d93fc86fd0 [GTask]) at ../gio/gtask.c:1361
g_task_return (type=<optimized out>, task=0x55d93fc86fd0 [GTask]) at ../gio/gtask.c:1430
g_task_return (task=0x55d93fc86fd0 [GTask], type=<optimized out>) at ../gio/gtask.c:1387
_request_wait_complete () at /lib64/libnm.so.0
_nm_client_notify_event_emit_parts () at /lib64/libnm.so.0
_dbus_handle_changes_commit () at /lib64/libnm.so.0
_nm_client_get_settings_call_cb () at /lib64/libnm.so.0
_nm_client_dbus_call_simple_cb () at /lib64/libnm.so.0
g_task_return_now (task=0x55d93f7bd6f0 [GTask]) at ../gio/gtask.c:1361
g_task_return (type=<optimized out>, task=0x55d93f7bd6f0 [GTask]) at ../gio/gtask.c:1430
g_task_return (task=0x55d93f7bd6f0 [GTask], type=<optimized out>) at ../gio/gtask.c:1387
g_dbus_connection_call_done (source=<optimized out>, result=<optimized out>, user_data=0x55d93f7bd6f0) at ../gio/gdbusconnection.c:5895
g_task_return_now (task=0x55d93f7bd7b0 [GTask]) at ../gio/gtask.c:1361
complete_in_idle_cb (task=task@entry=0x55d93f7bd7b0) at ../gio/gtask.c:1375
g_idle_dispatch (source=0x7f15b007c940, callback=0x7f15ca7e4850 <complete_in_idle_cb>, user_data=0x55d93f7bd7b0) at ../glib/gmain.c:6150
g_main_dispatch (context=0x55d93f77cde0) at ../glib/gmain.c:3344
g_main_context_dispatch_unlocked (context=0x55d93f77cde0) at ../glib/gmain.c:4152
g_main_context_iterate_unlocked.isra.0 (context=0x55d93f77cde0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4217
g_main_loop_run (loop=0x55d93f7589b0) at ../glib/gmain.c:4419
main (argc=19, argv=0x7fff77359138) at src/nmcli/nmcli.c:1044
Fixes: f377114d6e ('cli: connection: check for deprecated features')
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1872
When the lease is lost, NM tries to get a new by restarting the DHCP
transaction. However, it doesn't delete the existing l3cds (one from
the DHCP client with flag ONLY_FOR_ACD, the other from
NMDevice). Therefore, the l3cfg still tracks the ACD state of the
address as "external-removed", and when NM gets the same address via
DHCP, ACD is considered as failed; as a consequence, NM sends a
DECLINE message to the server.
Moreover, the l3cd added by NMDevice for DHCP has a zero ACD timeout,
and so it's not possible to do ACD again on the same address.
Remove those l3cds when the lease expires, so that any ACD state is
cleared and DHCP can perform ACD again.
Fixes: 240ec7f891 ('dhcp: implement ACD (address collision detection) for DHCPv4')
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1853
(cherry picked from commit a80fef9f37)
When the lease is lost, NM tries to get a new by restarting the DHCP
transaction. However, it doesn't delete the existing l3cds (one from
the DHCP client with flag ONLY_FOR_ACD, the other from
NMDevice). Therefore, the l3cfg still tracks the ACD state of the
address as "external-removed", and when NM gets the same address via
DHCP, ACD is considered as failed; as a consequence, NM sends a
DECLINE message to the server.
Moreover, the l3cd added by NMDevice for DHCP has a zero ACD timeout,
and so it's not possible to do ACD again on the same address.
Remove those l3cds when the lease expires, so that any ACD state is
cleared and DHCP can perform ACD again.
Fixes: 240ec7f891 ('dhcp: implement ACD (address collision detection) for DHCPv4')
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1853
Recent rpmbuild will delete the source directory on successful build.
With `makerepo.sh` that is bad, because we want that directory with the
git history. Pass "--noclean" to avoid that.
The main change is that lease address and pd getters changed and the new
functions are now used.
In addition, solved several conflicts due to disabled code and added
adapt header to new files.
Depending on the type of challenge used in the 2FA authentication, the
user input doesn't need to be hidden and sometimes it's even undesired
(it makes more difficult to enter the text).
Allow to VPN plugins to indicate that a secret that is being requested
is a 2FA challenge with ECHO mode enabled:
- When using auth dialog: accept a new option "ForceEcho" that can be
set to TRUE to enable ECHO.
- When using the fallback method: recognize the prefix
"x-dynamic-challenge-echo". This indicate both that ECHO should be enabled
and that this is a 2FA challenge (see previous commit).
The correct way to enable echo mode from VPN plugins is doing both
things: pass the hint prefixed with "x-dynamic-challenge-echo" and add the
option "ForceEcho=true" for the auth dialog.
An attempt to support ECHO mode from NM-openvpn was made by passing
"IsSecret=false", but it didn't work because nm-secret-agent-simple
ignores returned values for which "IsSecret=false". It's not a good idea
to start accepting them because we could break other plugins, and anyway
the challenge response is actually a secret, so it is better to keep it
as such and add this new "ForceEcho" option.
This is backwards compatible because existing plugins were not using the
tag nor the auth dialog option. Withouth them, the previous behaviour is
preserved. On the contrary, plugins that want to use this new feature
will need to bump their NM version dependency because old daemons will
not handle correctly the prefix tag.
Secret agents will need to be updated to check secret->force_echo if
they want to support this feature. Until they update, the only drawback
is that ECHO mode will be ignored and the user's input will be hidden.
Updated nmcli and nmtui to support ECHO mode.
Clients using nm-secret-agent-simple always asked for some default VPN
secrets, which are dependent on the VPN service, when the auth dialog
can't be used and the fallback method is used instead.
When using 2FA this has to be avoided in the 2nd step because those
default secrets were already requested and validated in the 1st step.
Fix it by adding a new "x-dynamic-challenge" prefix tag that can be used
in the hints received from the VPN plugin. This tag indicates that we
are in the 2nd step of a 2FA authentication. This way we know that we
don't have to request the default secrets this time. Note that the tag
name doesn't explicitly mention VPNs so it can be reused for other type
of connections in the future.
As the default secrets were requested always unconditionally when using
the fallback method, there is no possible workaround to this problem
that avoids having to change libnm-client.
The change is backwards compatible because VPN plugins were not using
the tag and the previous behaviour does not change if the tag is not
used. However, VPN plugins that want to properly support 2FA
aunthentication will need to bump the NM version dependency because
old daemons won't handle properly a hint with the new prefix tag.
Finally, move the macro that defines the "x-vpn-message:" tag in a public
header so it is more visible for users. It has been renamed and prefixed
with the NM_ namespace so it shouldn't collide with macros defined in
the VPN plugins.
The comparison checking for MAC address equality had previously been flipped around.
Fixes: b084ad7f2b ('libnm-core: canonicalize hardware addresses in settings')
(cherry picked from commit 641e717797)
It's simply not valid to read the ref-count without an atomic.
The compiler might optimize out the assignment to "r" and read the
_ref_count field multiple times. Thereby, we might at first appear
to be larger than > 1, and later pass 1 to compare-and-exchange.
We need an atomic get here.
Fixes: 19d4027824 ('refstr: inline nm_ref_string_{ref,unref}()')
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1847
(cherry picked from commit 5f7a027f59)
Older gcc versions don't like this. The _Pragam() itself is to workaround a
-Wnonnull-compare warning with gcc 14.
After all, we use compiler warning extensively. They are our linters and have
necessarily false positives. To make them usable across a wide range of
compilers, is a constant effort.
Here is another one.
The error:
./src/libnm-std-aux/nm-std-aux.h: In function ‘nm_utils_addr_family_other’:
./src/libnm-std-aux/nm-std-aux.h:230:36: error: expected expression before ‘#pragma’
230 | #define NM_PRAGMA_DIAGNOSTICS_PUSH _Pragma("GCC diagnostic push")
| ^~~~~~~
./src/libnm-std-aux/nm-std-aux.h:232:5: note: in expansion of macro ‘NM_PRAGMA_DIAGNOSTICS_PUSH’
232 | NM_PRAGMA_DIAGNOSTICS_PUSH _Pragma(_NM_PRAGMA_WARNING_DO(warning))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:291:9: note: in expansion of macro ‘NM_PRAGMA_WARNING_DISABLE’
291 | NM_PRAGMA_WARNING_DISABLE("-Wnonnull-compare"); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:953:9: note: in expansion of macro ‘nm_assert’
953 | nm_assert(true || NM_UNIQ_T(xx, uniq) == (x)); \
| ^~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:961:27: note: in expansion of macro ‘_NM_IN_SET’
961 | #define NM_IN_SET(x, ...) _NM_IN_SET(NM_UNIQ, ||, typeof(x), x, __VA_ARGS__)
| ^~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1493:15: note: in expansion of macro ‘NM_IN_SET’
1493 | nm_assert(NM_IN_SET((addr_family), NM_AF_INET, NM_AF_INET6))
| ^~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1502:9: note: in expansion of macro ‘nm_assert_addr_family’
1502 | nm_assert_addr_family(NM_UNIQ_T(_addr_family, uniq)); \
| ^~~~~~~~~~~~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1510:33: note: in expansion of macro ‘_NM_IS_IPv4’
1510 | #define NM_IS_IPv4(addr_family) _NM_IS_IPv4(NM_UNIQ, addr_family)
| ^~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1515:12: note: in expansion of macro ‘NM_IS_IPv4’
1515 | return NM_IS_IPv4(addr_family) ? NM_AF_INET6 : NM_AF_INET;
| ^~~~~~~~~~
Fixes: 62c1745f62 ('std-aux: suppress "-Wnonnull-compare" warning in nm_assert()')
(cherry picked from commit e4b154e1b0)
When doing reapply on linux bridge interface, NetworkManager will reset
the VLAN filtering and default PVID which cause PVID been readded to all
bridge ports regardless they are managed by NetworkManager.
This is because Linux kernel will re-add PVID to bridge port upon the
changes of bridge default-pvid value.
To fix the issue, this patch introduce netlink parsing code for
`vlan_filtering` and `default_pvid` of NMPlatformLnkBridge, and use that
to compare desired VLAN filtering settings, skip the reset of VLAN
filter if `default_pvid` and `vlan_filtering` are unchanged.
Signed-off-by: Gris Ge <fge@redhat.com>
(cherry picked from commit 02c34d538c)
GKeyfile changed something about how to handle invalid escape sequences.
As we don't want to test GKeyfile (per-se), just adjust to test to not
hit the problem.
This would fail with glib2-2.79.1-1.fc40:
# ./tools/run-nm-test.sh -m src/core/tests/config/test-config -p /config/set-values
TAP version 13
# random seed: R02Sb8afff1ec38ca5a1b7713e8c40eb4f56
# Start of config tests
# GLib-GIO-DEBUG: _g_io_module_get_default: Found default implementation local (GLocalVfs) for ?gio-vfs?
# (src/core/tests/config/test-config.c:1107) invalid value in config-data .intern.with-whitespace.key2 = (null) (instead of " b c\, d ")
./tools/run-nm-test.sh: line 307: 245847 Trace/breakpoint trap (core dumped) "${NMTST_DBUS_RUN_SESSION[@]}" "$TEST" "${TEST_ARGV[@]}"
exec "src/core/tests/config/test-config" failed with exit code 133
Upstream systemd fixed this compiler warning. What really needs to be
done, is re-importing the upstream code.
In the meantime, suppress the warning that hits on GCC 14.
This is a temporary workaround!
See-also: fdd84270df
When doing reapply on linux bridge interface, NetworkManager will reset
the VLAN filtering and default PVID which cause PVID been readded to all
bridge ports regardless they are managed by NetworkManager.
This is because Linux kernel will re-add PVID to bridge port upon the
changes of bridge default-pvid value.
To fix the issue, this patch introduce netlink parsing code for
`vlan_filtering` and `default_pvid` of NMPlatformLnkBridge, and use that
to compare desired VLAN filtering settings, skip the reset of VLAN
filter if `default_pvid` and `vlan_filtering` are unchanged.
Signed-off-by: Gris Ge <fge@redhat.com>
Older gcc versions don't like this. The _Pragam() itself is to workaround a
-Wnonnull-compare warning with gcc 14.
After all, we use compiler warning extensively. They are our linters and have
necessarily false positives. To make them usable across a wide range of
compilers, is a constant effort.
Here is another one.
The error:
./src/libnm-std-aux/nm-std-aux.h: In function ‘nm_utils_addr_family_other’:
./src/libnm-std-aux/nm-std-aux.h:230:36: error: expected expression before ‘#pragma’
230 | #define NM_PRAGMA_DIAGNOSTICS_PUSH _Pragma("GCC diagnostic push")
| ^~~~~~~
./src/libnm-std-aux/nm-std-aux.h:232:5: note: in expansion of macro ‘NM_PRAGMA_DIAGNOSTICS_PUSH’
232 | NM_PRAGMA_DIAGNOSTICS_PUSH _Pragma(_NM_PRAGMA_WARNING_DO(warning))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:291:9: note: in expansion of macro ‘NM_PRAGMA_WARNING_DISABLE’
291 | NM_PRAGMA_WARNING_DISABLE("-Wnonnull-compare"); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:953:9: note: in expansion of macro ‘nm_assert’
953 | nm_assert(true || NM_UNIQ_T(xx, uniq) == (x)); \
| ^~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:961:27: note: in expansion of macro ‘_NM_IN_SET’
961 | #define NM_IN_SET(x, ...) _NM_IN_SET(NM_UNIQ, ||, typeof(x), x, __VA_ARGS__)
| ^~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1493:15: note: in expansion of macro ‘NM_IN_SET’
1493 | nm_assert(NM_IN_SET((addr_family), NM_AF_INET, NM_AF_INET6))
| ^~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1502:9: note: in expansion of macro ‘nm_assert_addr_family’
1502 | nm_assert_addr_family(NM_UNIQ_T(_addr_family, uniq)); \
| ^~~~~~~~~~~~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1510:33: note: in expansion of macro ‘_NM_IS_IPv4’
1510 | #define NM_IS_IPv4(addr_family) _NM_IS_IPv4(NM_UNIQ, addr_family)
| ^~~~~~~~~~~
./src/libnm-std-aux/nm-std-aux.h:1515:12: note: in expansion of macro ‘NM_IS_IPv4’
1515 | return NM_IS_IPv4(addr_family) ? NM_AF_INET6 : NM_AF_INET;
| ^~~~~~~~~~
Fixes: 62c1745f62 ('std-aux: suppress "-Wnonnull-compare" warning in nm_assert()')
With a static array, we indicate that the argument must not be NULL.
Gcc-14.0.1-0.2.fc40 now warns against that:
CC src/libnm-base/libnm_base_la-nm-base.lo
In file included from ../src/libnm-std-aux/nm-default-std.h:102,
from ../src/libnm-glib-aux/nm-default-glib.h:11,
from ../src/libnm-glib-aux/nm-default-glib-i18n-lib.h:13,
from ../src/libnm-base/nm-base.c:3:
../src/libnm-base/nm-base.c: In function 'nm_net_devname_infiniband':
../src/libnm-std-aux/nm-std-aux.h:191:12: error: 'nonnull' argument 'name' compared to NULL [-Werror=nonnull-compare]
191 | if (expr) \
| ^
../src/libnm-std-aux/nm-std-aux.h:202:27: note: in expansion of macro '_NM_BOOLEAN_EXPR_IMPL'
202 | _NM_BOOLEAN_EXPR_IMPL(NM_UNIQ, expr))
| ^~~~~~~~~~~~~~~~~~~~~
../src/libnm-glib-aux/nm-macros-internal.h:1693:31: note: in expansion of macro 'NM_BOOLEAN_EXPR'
1693 | #define _G_BOOLEAN_EXPR(expr) NM_BOOLEAN_EXPR(expr)
| ^~~~~~~~~~~~~~~
/usr/include/glib-2.0/glib/gmacros.h:1244:43: note: in expansion of macro '_G_BOOLEAN_EXPR'
1244 | #define G_LIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR(expr), 1))
| ^~~~~~~~~~~~~~~
/usr/include/glib-2.0/glib/gmessages.h:656:9: note: in expansion of macro 'G_LIKELY'
656 | if (G_LIKELY (expr)) \
| ^~~~~~~~
../src/libnm-base/nm-base.c:57:5: note: in expansion of macro 'g_return_val_if_fail'
57 | g_return_val_if_fail(name, NULL);
| ^~~~~~~~~~~~~~~~~~~~
../src/libnm-core-impl/nm-setting-wireguard.c: In function '_nm_wireguard_peer_set_public_key_bin':
../src/libnm-core-impl/nm-setting-wireguard.c:316:8: error: 'nonnull' argument 'public_key' compared to NULL [-Werror=nonnull-compare]
316 | if (!public_key)
| ^
Convert these checks to an nm_assert() to suppress the warning.
(cherry picked from commit 7a031eef5d)
When we use a "static" array declarator to a function, we understand
and tell the compiler that the argument must not be NULL.
But now gcc-14.0.1-0.2.fc40 starts warning about NULL checks for
such arguments.
static void foo(char args[static 10]) {
nm_assert(args);
sprintf(args, "hi");
}
Granted, the compiler is right, and we know that this condition is not
supposed to be violated. A logical thing would be just to drop the
assertion.
Instead, suppress "-Wnonnull-compare" warnings inside a nm_assert(). An
nm_assert() is more than a run time check, it's an additional
self-documenting code of the invariants.
It's fine to assert for something that is true. Actually, all the
conditions that we assert against, hold. The compiler telling us that
the condition that we assert against is valid, is not useful.
(cherry picked from commit 62c1745f62)
Otherwise, gcc-14.0.1-0.2.fc40 warns:
../src/libnm-core-impl/nm-utils.c: In function _nm_utils_strstrdictkey_create:
../src/libnm-core-impl/nm-utils.c:5076:16: error: allocation of insufficient size '1' for type 'NMUtilsStrStrDictKey' {aka 'struct _NMUtilsStrStrDictKey'} with size '2' [-Werror=alloc-size]
5076 | return g_malloc0(1);
| ^~~~~~~~~~~~
(cherry picked from commit 63ab0d926d)
gcc-14.0.1-0.2.fc40 warns:
CC src/libnm-core-impl/libnm_core_impl_la-nm-setting-team.lo
../src/libnm-core-impl/nm-setting-team.c: In function nm_team_link_watcher_new_ethtool:
../src/libnm-core-impl/nm-setting-team.c:127:13: error: allocation of insufficient size 16 for type NMTeamLinkWatcher with size 48 [-Werror=alloc-size]
127 | watcher = g_malloc(nm_offsetofend(NMTeamLinkWatcher, ethtool));
| ^
(cherry picked from commit 5715feebe7)
With a static array, we indicate that the argument must not be NULL.
Gcc-14.0.1-0.2.fc40 now warns against that:
CC src/libnm-base/libnm_base_la-nm-base.lo
In file included from ../src/libnm-std-aux/nm-default-std.h:102,
from ../src/libnm-glib-aux/nm-default-glib.h:11,
from ../src/libnm-glib-aux/nm-default-glib-i18n-lib.h:13,
from ../src/libnm-base/nm-base.c:3:
../src/libnm-base/nm-base.c: In function 'nm_net_devname_infiniband':
../src/libnm-std-aux/nm-std-aux.h:191:12: error: 'nonnull' argument 'name' compared to NULL [-Werror=nonnull-compare]
191 | if (expr) \
| ^
../src/libnm-std-aux/nm-std-aux.h:202:27: note: in expansion of macro '_NM_BOOLEAN_EXPR_IMPL'
202 | _NM_BOOLEAN_EXPR_IMPL(NM_UNIQ, expr))
| ^~~~~~~~~~~~~~~~~~~~~
../src/libnm-glib-aux/nm-macros-internal.h:1693:31: note: in expansion of macro 'NM_BOOLEAN_EXPR'
1693 | #define _G_BOOLEAN_EXPR(expr) NM_BOOLEAN_EXPR(expr)
| ^~~~~~~~~~~~~~~
/usr/include/glib-2.0/glib/gmacros.h:1244:43: note: in expansion of macro '_G_BOOLEAN_EXPR'
1244 | #define G_LIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR(expr), 1))
| ^~~~~~~~~~~~~~~
/usr/include/glib-2.0/glib/gmessages.h:656:9: note: in expansion of macro 'G_LIKELY'
656 | if (G_LIKELY (expr)) \
| ^~~~~~~~
../src/libnm-base/nm-base.c:57:5: note: in expansion of macro 'g_return_val_if_fail'
57 | g_return_val_if_fail(name, NULL);
| ^~~~~~~~~~~~~~~~~~~~
../src/libnm-core-impl/nm-setting-wireguard.c: In function '_nm_wireguard_peer_set_public_key_bin':
../src/libnm-core-impl/nm-setting-wireguard.c:316:8: error: 'nonnull' argument 'public_key' compared to NULL [-Werror=nonnull-compare]
316 | if (!public_key)
| ^
Convert these checks to an nm_assert() to suppress the warning.
When we use a "static" array declarator to a function, we understand
and tell the compiler that the argument must not be NULL.
But now gcc-14.0.1-0.2.fc40 starts warning about NULL checks for
such arguments.
static void foo(char args[static 10]) {
nm_assert(args);
sprintf(args, "hi");
}
Granted, the compiler is right, and we know that this condition is not
supposed to be violated. A logical thing would be just to drop the
assertion.
Instead, suppress "-Wnonnull-compare" warnings inside a nm_assert(). An
nm_assert() is more than a run time check, it's an additional
self-documenting code of the invariants.
It's fine to assert for something that is true. Actually, all the
conditions that we assert against, hold. The compiler telling us that
the condition that we assert against is valid, is not useful.
