NetworkManager/SOURCES/1005-fix-race-condition-while-enumerating-devices-rhel25808.patch

67 lines
2.9 KiB
Diff

From 8ff08068342d1d8efe1e6d6c9a241e3395641a76 Mon Sep 17 00:00:00 2001
From: Beniamino Galvani <bgalvani@redhat.com>
Date: Thu, 21 Mar 2024 09:45:15 +0100
Subject: [PATCH 2/2] manager: fix race condition while enumerating devices at
startup
While enumerating devices at startup, we take a snapshot of existing
links from platform and we start creating device instances for
them. It's possible that in the meantime, while processing netlink
events in platform_link_added(), a link gets renamed. If that happens,
then we have two different views of the same ifindex: the cached link
from `links` and the link in platform.
This can cause issues: in platform_link_added() we create the device
with the cached name; then in NMDevice's constructor(), we look up
from platform the ifindex for the given name. Because of the rename,
this lookup can match a newly created, different link.
The end result is that the ifindex from the initial snapshot doesn't
get a NMDevice and is not handled by NetworkManager.
Fix this problem by fetching the latest version of the link from
platform to make sure we have a consistent view of the state.
https://issues.redhat.com/browse/RHEL-25808
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1897
(cherry picked from commit de130df3e2207dc015c4fa82ecf766be2851532c)
(cherry picked from commit 6f3739e76f1f31d71bc3fbd7a4b0955071d59cc4)
---
src/core/nm-manager.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/src/core/nm-manager.c b/src/core/nm-manager.c
index 7f94f7cd9c..a77ba9d3b1 100644
--- a/src/core/nm-manager.c
+++ b/src/core/nm-manager.c
@@ -4438,10 +4438,25 @@ platform_query_devices(NMManager *self)
links = nm_platform_link_get_all(priv->platform);
if (!links)
return;
+
for (i = 0; i < links->len; i++) {
- const NMPlatformLink *link = NMP_OBJECT_CAST_LINK(links->pdata[i]);
+ const NMPlatformLink *elem = NMP_OBJECT_CAST_LINK(links->pdata[i]);
+ const NMPlatformLink *link;
const NMConfigDeviceStateData *dev_state;
+ /*
+ * @links is an immutable snapshot of the platform links captured before
+ * the loop was started. It's possible that in the meantime, while
+ * processing netlink events in platform_link_added(), a link was
+ * renamed. If that happens, we have 2 different views of the same
+ * ifindex: the one from @links and the one from platform. This can
+ * cause race conditions; make sure to use the latest known version of
+ * the link.
+ */
+ link = nm_platform_link_get(priv->platform, elem->ifindex);
+ if (!link)
+ continue;
+
dev_state = nm_config_device_state_get(priv->config, link->ifindex);
platform_link_added(self,
link->ifindex,
--
2.41.0