Re: [PATCH] gpib: cb7210: Fix region leak when request_irq fails

[Greg KH]

On Fri, May 15, 2026 at 03:39:52PM +0800, Hongling Zeng wrote:
> When request_irq() fails, the region allocated by request_region()
> is not released. Fix this by adding an error handling path with
> proper goto labels to release the region.
> 
> Fixes: 82e3508046f9b ("gpib: cb7210: add isa support module")
> Signed-off-by: Hongling Zeng <zenghongling@xxxxxxxxxx>
> ---
>  drivers/gpib/cb7210/cb7210.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpib/cb7210/cb7210.c b/drivers/gpib/cb7210/cb7210.c
> index 6dd8637c5964..7b0af517cf14 100644
> --- a/drivers/gpib/cb7210/cb7210.c
> +++ b/drivers/gpib/cb7210/cb7210.c
> @@ -1049,7 +1049,8 @@ static int cb_isa_attach(struct gpib_board *board, const struct gpib_board_confi
>  	if (!request_region(config->ibbase, cb7210_iosize, DRV_NAME)) {
>  		dev_err(board->gpib_dev, "ioports starting at 0x%x are already in use\n",
>  			config->ibbase);
> -		return -EBUSY;
> +		retval = -EBUSY;
> +		goto err_release_region;
>  	}
>  	nec_priv->iobase = config->ibbase;
>  	cb_priv->fifo_iobase = nec7210_iobase(cb_priv);
> @@ -1062,11 +1063,16 @@ static int cb_isa_attach(struct gpib_board *board, const struct gpib_board_confi
>  	// install interrupt handler
>  	if (request_irq(config->ibirq, cb7210_interrupt, isr_flags, DRV_NAME, board)) {
>  		dev_err(board->gpib_dev, "failed to obtain IRQ %d\n", config->ibirq);
> -		return -EBUSY;
> +		ret = -EBUSY;
> +		goto err_release_region;
>  	}
>  	cb_priv->irq = config->ibirq;
>  
>  	return cb7210_init(cb_priv, board);
> +
> +err_release_region:
> +	release_region(nec7210_iobase(cb_priv), cb7210_iosize);
> +	return retval;
>  }
>  
>  static void cb_isa_detach(struct gpib_board *board)
> -- 
> 2.25.1
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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