Re: [PATCH][V2] brcmfmac: fix leak of mypkt on error return path

Arend Van Spriel
2019-04-09T11:50:43Z

On 4/9/2019 1:43 PM, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
>
> Currently if the call to brcmf_sdiod_set_backplane_window fails then
> then error return path leaks mypkt. Fix this by returning by a new
> error path labelled 'out' that calls brcmu_pkt_buf_free_skb to free
> mypkt. Also remove redundant check on err before calling
> brcmf_sdiod_skbuff_write.
>
> Addresses-Coverity: ("Resource Leak")
> Fixes: a7c3aa1509e2 ("brcmfmac: Remove brcmf_sdiod_addrprep()")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
>
> V2: Remove redundant check on err before calling
> brcmf_sdiod_skbuff_write, kudos to Dan Carpenter and Arend Van Spriel
> for spotting this.
>
> ---
> drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
> index ec129864cc9c..60aede5abb4d 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
> @@ -628,15 +628,13 @@ int brcmf_sdiod_send_buf(struct brcmf_sdio_dev *sdiodev, u8 *buf, uint nbytes)
>
> err = brcmf_sdiod_set_backplane_window(sdiodev, addr);
> if (err)
> - return err;
> + goto out;
>
> addr &= SBSDIO_SB_OFT_ADDR_MASK;
> addr |= SBSDIO_SB_ACCESS_2_4B_FLAG;
>
> - if (!err)
> - err = brcmf_sdiod_skbuff_write(sdiodev, sdiodev->func2, addr,
> - mypkt);
> -
> + err = brcmf_sdiod_skbuff_write(sdiodev, sdiodev->func2, addr, mypkt);
> +out:

I am fine with it, but my suggestion was a bit different:

err = brcmf_sdiod_set_backplane_window(sdiodev, addr);
if (!err) {
addr &= SBSDIO_SB_OFT_ADDR_MASK;
addr |= SBSDIO_SB_ACCESS_2_4B_FLAG;
err = brcmf_sdiod_skbuff_write(sdiodev, sdiodev->func2,
addr, mypkt);
}

> brcmu_pkt_buf_free_skb(mypkt);
>
> return err;
>