Re: [PATCH v2] usb: xhci: Fix memory leak in xhci_disable_slot()

From: Greg KH
Date: Thu Jan 08 2026 - 10:53:56 EST


On Thu, Jan 08, 2026 at 02:11:08PM +0000, Zilin Guan wrote:
> xhci_alloc_command() allocates a command structure and, when the
> second argument is true, also allocates a completion structure.
> Currently, the error handling path in xhci_disable_slot() only frees
> the command structure using kfree(), causing the completion structure
> to leak.
>
> Use xhci_free_command() instead of kfree(). xhci_free_command() correctly
> frees both the command structure and the associated completion structure.
> Since the command structure is allocated with zero-initialization,
> command->in_ctx is NULL and will not be erroneously freed by
> xhci_free_command().
>
> This bug was found using an experimental static analysis tool we are
> developing. The tool is based on the LLVM framework and is specifically
> designed to detect memory management issues. It is currently under
> active development and not yet publicly available, but we plan to
> open-source it after our research is published.
>
> The analysis was performed on Linux kernel v6.13-rc1.

That is a very old kernel version, from December 2024, please redo this
to verify it is relevent to todays tree.

thanks,

greg k-h