CVE-2026-53286idpf: fix double free and use-after-free in aux device error paths

Official description

In the Linux kernel, the following vulnerability has been resolved: idpf: fix double free and use-after-free in aux device error paths When auxiliary_device_add() fails in idpf_plug_vport_aux_dev() or idpf_plug_core_aux_dev(), the err_aux_dev_add label calls auxiliary_device_uninit() and falls through to err_aux_dev_init. The uninit call will trigger put_device(), which invokes the release callback (idpf_vport_adev_release / idpf_core_adev_release) that frees iadev. The fall-through then reads adev->id from the freed iadev for ida_free() and double-frees iadev with kfree(). Free the IDA slot and clear the back-pointer before uninit, while adev is still valid, then return immediately. Commit 65637c3a1811 ("idpf: fix UAF in RDMA core aux dev deinitialization") fixed the same use-after-free in the matching unplug path in this file but missed both probe error paths.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/722b91d5086a249318c9d0e2b36aeac80ba8c808
• https://git.kernel.org/stable/c/f319de7074e1728a9f9ff7134257360c694ec2b2
• https://git.kernel.org/stable/c/6c77b9510829a424d1b74409b7db9456e3522871