Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: openvswitch: vport: fix self-deadlock on release of tunnel ports vports are used concurrently and protected by RCU, so netdev_put() must happen after the RCU grace period. So, either in an RCU call or after the synchronize_net(). The rtnl_delete_link() must happen under RTNL and so can't be executed in RCU context. Calling synchronize_net() while holding RTNL is not a good idea for performance and system stability under load in general, so calling netdev_put() in RCU call is the right solution here. However, when the device is deleted, rtnl_unlock() will call netdev_run_todo() and block until all the references are gone. In the current code this means that we never reach the call_rcu() and the vport is never freed and the reference is never released, causing a self-deadlock on device removal. Fix that by moving the rcu_call() before the rtnl_unlock(), so the scheduled RCU callback will be executed when synchronize_net() is called from the rtnl_unlock()->netdev_run_todo() while the RTNL itself is already released.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 9d56aced21fb9c104e8a3f3be9b21fbafe448ffc before 8ae6c15fc473c9ad03b0173330cce9a092c76154; affected 42f0d3d81209654c08ffdde5a34b9b92d2645896 before c741433f6c8dcdecd1d9549d89053761fd1ea413; affected bbe7bd722bfaea36aab3da6cc60fb4a05c644643 before 6522d59fb7de55ce0f0f285d962243ddffebb01f; affected 98b726ab5e2a4811e27c28e4d041f75bba147eab before 3df75fff46b1517eb479d8e6b8e3500763715dd0; affected 6931d21f87bc6d657f145798fad0bf077b82486c before 366c482965c673565ecb8bcfb15d5548f13a6a10; affected 6931d21f87bc6d657f145798fad0bf077b82486c before aa69918bd418e700309fdd08509dba324fb24296; affected b8c56a3fc5d879c0928f207a756b0f067f06c6a8; affected 6.1.168 before 6.1.175; affected 6.6.131 before 6.6.140; affected 6.12.80 before 6.12.88; affected 6.18.21 before 6.18.30; affected 6.19.11 before 6.20 |
| Linux / Linux | affected 7.0; unaffected 0 before 7.0; unaffected 6.1.175 through 6.1.*; unaffected 6.6.140 through 6.6.*; unaffected 6.12.88 through 6.12.*; unaffected 6.18.30 through 6.18.*; unaffected 7.0.7 through 7.0.*; unaffected 7.1 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/8ae6c15fc473c9ad03b0173330cce9a092c76154
- https://git.kernel.org/stable/c/c741433f6c8dcdecd1d9549d89053761fd1ea413
- https://git.kernel.org/stable/c/6522d59fb7de55ce0f0f285d962243ddffebb01f
- https://git.kernel.org/stable/c/3df75fff46b1517eb479d8e6b8e3500763715dd0
- https://git.kernel.org/stable/c/366c482965c673565ecb8bcfb15d5548f13a6a10
- https://git.kernel.org/stable/c/aa69918bd418e700309fdd08509dba324fb24296
ADP enrichment
No English description supplied.