net/smc: Fix possible leaked pernet namespace in smc_init()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: net/smc: Fix possible leaked pernet namespace in smc_init() In smc_init(), register_pernet_subsys(&smc_net_stat_ops) is called without any error handling. If it fails, registering of &smc_net_ops won't be reverted. And if smc_nl_init() fails, &smc_net_stat_ops itself won't be reverted. This leaves wild ops in subsystem linkedlist and when another module tries to call register_pernet_operations() it triggers page fault: BUG: unable to handle page fault for address: fffffbfff81b964c RIP: 0010:register_pernet_operations+0x1b9/0x5f0 Call Trace: <TASK> register_pernet_subsys+0x29/0x40 ebtables_init+0x58/0x1000 [ebtables] ...

References

• https://git.kernel.org/stable/c/61defd6450a9ef4a1487090449999b0fd83518ef
• https://git.kernel.org/stable/c/c97daf836f7caf81d3144b8cd2b2a51f9bc3bd09
• https://git.kernel.org/stable/c/62ff373da2534534c55debe6c724c7fe14adb97f