Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
tun: free page on build_skb failure in tun_xdp_one()
When build_skb() fails in tun_xdp_one(), the function sets ret to -ENOMEM and jumps to the out label, which returns without freeing the page that vhost_net_build_xdp() allocated for the frame. As with the short-frame rejection path, tun_sendmsg() discards the per-buffer error and still returns total_len, so vhost_tx_batch() takes the success path and never frees the page. Each build_skb() failure in a batch leaks one page-frag chunk.
Free the page before taking the error path, matching the put_page() the other error exits of tun_xdp_one() already perform.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , Ubuntu 20.04 ELS
- Affected packages:
- kernel @ 5.10.0 (+7 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 9.2 ESU | Planned | — |
| Amazon Linux 2023 | Planned | — |
| Debian 11 | Released |
37 kernels
|
| Debian 11 cloud | Released |
17 kernels
|
| Debian 12 | Released |
40 kernels
|
| Debian 13 | Released |
10 kernels
|