Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
net: ena: Fix incorrect descriptor free behavior
ENA has two types of TX queues:
- queues which only process TX packets arriving from the network stack
- queues which only process TX packets forwarded to it by XDP_REDIRECT or XDP_TX instructions
The ena_free_tx_bufs() cycles through all descriptors in a TX queue and unmaps + frees every descriptor that hasn’t been acknowledged yet by the device (uncompleted TX transactions). The function assumes that the processed TX queue is necessarily from the first category listed above and ends up using napi_consume_skb() for descriptors belonging to an XDP specific queue.
This patch solves a bug in which, in case of a VF reset, the descriptors aren’t freed correctly, leading to crashes.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 6 ELS , Oracle Linux 6 ELS , Ubuntu 18.04 ELS
- Affected packages:
- kernel @ 4.18.0 (+9 more)
In the Linux kernel, the following vulnerability has been resolved:
net: ena: Fix incorrect descriptor free behavior
ENA has two types of TX queues:
- queues which only process TX packets arriving from the network stack
- queues which only process TX packets forwarded to it by XDP_REDIRECT or XDP_TX instructions
The ena_free_tx_bufs() cycles through all descriptors in a TX queue and unmaps + frees every descriptor that hasn’t been acknowledged yet by the device (uncompleted TX transactions). The function assumes that the processed TX queue is necessarily from the first category listed above and ends up using napi_consume_skb() for descriptors belonging to an XDP specific queue.
This patch solves a bug in which, in case of a VF reset, the descriptors aren’t freed correctly, leading to crashes.