Re: [PATCH v2] usb: host: xhci: Fix potential memory leak in xhci_alloc_stream_info()

From: Greg KH
Date: Fri Jul 01 2022 - 03:28:17 EST


On Fri, Jul 01, 2022 at 03:10:02PM +0800, Jianglei Nie wrote:
> xhci_alloc_stream_info() allocates stream context array for stream_info
> ->stream_ctx_array with xhci_alloc_stream_ctx(). When some error occurs,
> stream_info->stream_ctx_array is not released, which will lead to a
> memory leak.
>
> We can fix it by releasing the stream_info->stream_ctx_array with
> xhci_free_stream_ctx() on the error path to avoid the potential memory
> leak.
>
> Signed-off-by: Jianglei Nie <niejianglei2021@xxxxxxx>
> ---
> drivers/usb/host/xhci-mem.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
> index 8c19e151a945..9e56aa28efcd 100644
> --- a/drivers/usb/host/xhci-mem.c
> +++ b/drivers/usb/host/xhci-mem.c
> @@ -641,7 +641,7 @@ struct xhci_stream_info *xhci_alloc_stream_info(struct xhci_hcd *xhci,
> num_stream_ctxs, &stream_info->ctx_array_dma,
> mem_flags);
> if (!stream_info->stream_ctx_array)
> - goto cleanup_ctx;
> + goto cleanup_ring_array;
> memset(stream_info->stream_ctx_array, 0,
> sizeof(struct xhci_stream_ctx)*num_stream_ctxs);
>
> @@ -702,6 +702,11 @@ struct xhci_stream_info *xhci_alloc_stream_info(struct xhci_hcd *xhci,
> }
> xhci_free_command(xhci, stream_info->free_streams_command);
> cleanup_ctx:
> + xhci_free_stream_ctx(xhci,
> + stream_info->num_stream_ctxs,
> + stream_info->stream_ctx_array,
> + stream_info->ctx_array_dma);
> +cleanup_ring_array:
> kfree(stream_info->stream_rings);
> cleanup_info:
> kfree(stream_info);
> --
> 2.25.1
>

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
a patch that has triggered this response. He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created. Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- This looks like a new version of a previously submitted patch, but you
did not list below the --- line any changes from the previous version.
Please read the section entitled "The canonical patch format" in the
kernel file, Documentation/SubmittingPatches for what needs to be done
here to properly describe this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.

thanks,

greg k-h's patch email bot