CVE-2026-90077

/// Technical description

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.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References