In the Linux kernel, the following vulnerability has been resolved:
sctp: sysctl: udp_port: 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
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
The 'net' structure can be obtained from the table->data using container_of().
Note that table->data could also be used directly, but that would increase the size of this fix, while 'sctp.ctl_sock' still needs to be retrieved from 'net' structure.