On Thu, Jan 08, 2026 at 04:28:42PM +0100, Greg KH wrote:
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
Sorry for the confusion caused by our description. While the static analysis was indeed performed on v6.13-rc1, we have manually verified that the bug still exists in the latest mainline kernel before submitting the patch.
I will clarify this distinction in the v3 patch and update the version information.
Thanks, Zilin Guan