CVE-2023-53338 (GCVE-0-2023-53338)
Vulnerability from cvelistv5
Published
2025-09-17 14:56
Modified
2025-09-17 14:56
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
lwt: Fix return values of BPF xmit ops
BPF encap ops can return different types of positive values, such like
NET_RX_DROP, NET_XMIT_CN, NETDEV_TX_BUSY, and so on, from function
skb_do_redirect and bpf_lwt_xmit_reroute. At the xmit hook, such return
values would be treated implicitly as LWTUNNEL_XMIT_CONTINUE in
ip(6)_finish_output2. When this happens, skbs that have been freed would
continue to the neighbor subsystem, causing use-after-free bug and
kernel crashes.
To fix the incorrect behavior, skb_do_redirect return values can be
simply discarded, the same as tc-egress behavior. On the other hand,
bpf_lwt_xmit_reroute returns useful errors to local senders, e.g. PMTU
information. Thus convert its return values to avoid the conflict with
LWTUNNEL_XMIT_CONTINUE.
References
Impacted products
| Vendor | Product | Version | |||||||
|---|---|---|---|---|---|---|---|---|---|
| ▼ | Linux | Linux |
Version: 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 Version: 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 Version: 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 Version: 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 Version: 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 Version: 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 Version: 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 |
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|
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"dateReserved": "2025-09-16T16:08:59.565Z",
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