[PATCH v2] nvme/070: add a test for Identify CNS 07h NULL pointer dereference

[Shin'ichiro Kawasaki]

On Aug 04, 2026 / 10:46, Guixin Liu wrote:
> nvmet_execute_identify_nslist() handles both the Active Namespace ID list
> (CNS 02h) and the per-command-set variant (CNS 07h). For CNS 07h it
> filtered the list on req->ns->csi, but this handler never resolves
> req->ns, so it is always NULL. As soon as an enabled namespace with an
> NSID above the requested value exists, the target dereferenced a NULL
> pointer and oopsed.
> 
> This test connects a target with a single namespace and issues an
> Identify with CNS 07h starting from NSID 0, which is exactly the
> condition that triggered the crash. Without the kernel fix [0] the target
> oopses; with it the command completes normally.
> 
> [0] https://lore.kernel.org/linux-nvme/20260730043105.3071328-2-kanie@linux.alibaba.com/
> 
> Suggested-by: Christoph Hellwig <hch at lst.de>
> Signed-off-by: Guixin Liu <kanie at linux.alibaba.com>
> ---
> v1 -> v2:
>   - Use "nvme list-ns --csi=0" instead of a raw admin-passthru to issue
>     Identify CNS 07h, as suggested by Nilay and Shinichiro; it drives the
>     same target code path via the existing nvme-cli subcommand.

Thanks for this v2 patch. It looks good to me. I will wait for the kernel side
fix get settled on Linus master branch before I apply this patch.