In the Linux kernel, the following vulnerability has been resolved:

sctp: sysctl: plpmtud_probe_interval: avoid using current->nsproxy

As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:

- Inconsistency: getting info from the reader's/writer's netns vs only
  from the opener's netns.

- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
  (null-ptr-deref), e.g. when the current task is exiting, as spotted by
  syzbot [1] using acct(2).

The 'net' structure can be obtained from the table->data using
container_of().

Note that table->data could also be used directly, as this is the only
member needed from the 'net' structure, but that would increase the size
of this fix, to use '*data' everywhere 'net->sctp.probe_interval' is
used.

https://git.kernel.org/stable/c/284a221f8fa503628432c7bb5108277c688c6ffa

https://git.kernel.org/stable/c/44ee8635922b6eb940faddb961a8347c6857d722

https://git.kernel.org/stable/c/6259d2484d0ceff42245d1f09cc8cb6ee72d847a

https://git.kernel.org/stable/c/bcf8c60074e81ed2ac2d35130917175a3949c917