linux-kernel - Re: [PATCH] PCI: endpoint: Fix a NULL vs IS_ERR() check in pci_epf_test_init_dma

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20220711215153.GA691840@bhelgaas>
Date:   Mon, 11 Jul 2022 16:51:53 -0500
From:   Bjorn Helgaas <helgaas@...nel.org>
To:     Peng Wu <wupeng58@...wei.com>
Cc:     kishon@...com, lpieralisi@...nel.org, kw@...ux.com,
        bhelgaas@...gle.com, linux-pci@...r.kernel.org,
        linux-kernel@...r.kernel.org, liwei391@...wei.com,
        Dan Carpenter <dan.carpenter@...cle.com>,
        Shunsuke Mie <mie@...l.co.jp>
Subject: Re: [PATCH] PCI: endpoint: Fix a NULL vs IS_ERR() check in
 pci_epf_test_init_dma_chan()

[+cc Dan, Shunsuke]

On Thu, Jul 07, 2022 at 01:12:15PM +0000, Peng Wu wrote:
> On failure, dma_request_channel() returns NULL and not a
> ERR_PTR() value. Fix return value checking by using is NULL.
> 
> Signed-off-by: Peng Wu <wupeng58@...wei.com>

Thanks for the patch.  Dan posted the same thing later [1].

I'd be happy to do this, but Shunsuke suggested that the rx path
should be changed similarly, so I'll look for a patch that does both.

[1] https://lore.kernel.org/r/YsftwaVowtU9/pgn@kili
[2] https://lore.kernel.org/r/CANXvt5rK98-cEMgpzopY9POOK8a5=VDib8uKPLgJakOG=hRfwQ@mail.gmail.com

> ---
>  drivers/pci/endpoint/functions/pci-epf-test.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index 34aac220dd4c..eed6638ab71d 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -221,7 +221,7 @@ static int pci_epf_test_init_dma_chan(struct pci_epf_test *epf_test)
>  	filter.dma_mask = BIT(DMA_MEM_TO_DEV);
>  	dma_chan = dma_request_channel(mask, epf_dma_filter_fn, &filter);
>  
> -	if (IS_ERR(dma_chan)) {
> +	if (!dma_chan) {
>  		dev_info(dev, "Failed to get private DMA tx channel. Falling back to generic one\n");
>  		goto fail_back_rx;
>  	}
> -- 
> 2.17.1
>