In the Linux kernel, the following vulnerability has been resolved:
net: fix a resource leak in copy_net_ns() error handling path
Currently, preinit_net() does two things:
(1) call ns_common_init() which might fail (2) initialize resources which does not fail
However, preinit_net() is returning early when (1) fails, and copy_net_ns() is jumping to the dec_ucounts: label. As a result, resources allocated by net_alloc() are leaking. We need to call key_remove_domain() and net_passive_dec() in order to release resources allocated by net_alloc().
We cannot simply jump to the put_userns: label when preinit_net() failed, for (2) is not yet done. But we can reorder (1) and (2), for there is no dependency between (1) and (2). Therefore, this patch decouples (1) from preinit_net() and changes preinit_net() back to a void function, and calls ns_common_init() after preinit_net() succeeded. Then, we can jump to immediately after ns_common_free() of the put_userns: label.
Prioritise with Active Threat Intelligence
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub