CVE-2025-38273

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net: tipc: fix refcount warning in tipc_aead_encrypt<br /> <br /> syzbot reported a refcount warning [1] caused by calling get_net() on<br /> a network namespace that is being destroyed (refcount=0). This happens<br /> when a TIPC discovery timer fires during network namespace cleanup.<br /> <br /> The recently added get_net() call in commit e279024617134 ("net/tipc:<br /> fix slab-use-after-free Read in tipc_aead_encrypt_done") attempts to<br /> hold a reference to the network namespace. However, if the namespace<br /> is already being destroyed, its refcount might be zero, leading to the<br /> use-after-free warning.<br /> <br /> Replace get_net() with maybe_get_net(), which safely checks if the<br /> refcount is non-zero before incrementing it. If the namespace is being<br /> destroyed, return -ENODEV early, after releasing the bearer reference.<br /> <br /> [1]: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2