CVE-2026-90228nvmet: fix NULL pointer dereference in nvmet_execute_identify_ns_zns()

Official description

In the Linux kernel, the following vulnerability has been resolved: nvmet: fix NULL pointer dereference in nvmet_execute_identify_ns_zns() When a host issues an Identify command with CNS 05h (I/O Command Set specific Identify Namespace) and CSI 02h (ZNS) targeting a file-backed namespace, nvmet_execute_identify_ns_zns() calls bdev_is_zoned() on req->ns->bdev. A file-backed namespace has no block device, so req->ns->bdev is NULL and bdev_is_zoned() dereferences it, oopsing. The I/O command set is selected by the host-supplied CSI field and the command is routed here whenever CONFIG_BLK_DEV_ZONED is enabled, independent of the namespace backing type, so any file-backed namespace is exposed. Reject the command with Invalid Field when the namespace is not backed by a block device.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/1ce8faf90eb0bf5599b90db38500aefea9426485
• https://git.kernel.org/stable/c/b873099944dae5702b4b6db6814d1f1e8d4cfb00
• https://git.kernel.org/stable/c/ff28a93a895912010a7827a0e1445ebe8be53b4d
• https://git.kernel.org/stable/c/cc29f7082b7ab5e0337f27d1fef16359f05fcffa
• https://git.kernel.org/stable/c/1fb1236312ee1a600de6b3ca560f0b3fd5a50471
• https://git.kernel.org/stable/c/0b4cf43f9ca7118590a338de900edbd6047cd89f
• https://git.kernel.org/stable/c/f594863967d87b7fcbff6e724d51135fd701a13d