Re: [PATCH 153/190] Revert "media: usb: gspca: add a missed return-value check for do_command"

[Greg Kroah-Hartman]

On Wed, Apr 21, 2021 at 03:00:28PM +0200, Greg Kroah-Hartman wrote:
> This reverts commit 5ceaf5452c1b2a452dadaf377f9f07af7bda9cc3.
> 
> Commits from @umn.edu addresses have been found to be submitted in "bad
> faith" to try to test the kernel community's ability to review "known
> malicious" changes.  The result of these submissions can be found in a
> paper published at the 42nd IEEE Symposium on Security and Privacy
> entitled, "Open Source Insecurity: Stealthily Introducing
> Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University
> of Minnesota) and Kangjie Lu (University of Minnesota).
> 
> Because of this, all submissions from this group must be reverted from
> the kernel tree and will need to be re-reviewed again to determine if
> they actually are a valid fix.  Until that work is complete, remove this
> change to ensure that no problems are being introduced into the
> codebase.
> 
> Cc: Kangjie Lu <kjlu@xxxxxxx>
> Cc: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/media/usb/gspca/cpia1.c | 8 ++------
>  1 file changed, 2 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/media/usb/gspca/cpia1.c b/drivers/media/usb/gspca/cpia1.c
> index d93d384286c1..99e594559a0c 100644
> --- a/drivers/media/usb/gspca/cpia1.c
> +++ b/drivers/media/usb/gspca/cpia1.c
> @@ -537,14 +537,10 @@ static int do_command(struct gspca_dev *gspca_dev, u16 command,
>  		}
>  		if (sd->params.qx3.button) {
>  			/* button pressed - unlock the latch */
> -			ret = do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
> +			do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
>  				   3, 0xdf, 0xdf, 0);
> -			if (ret)
> -				return ret;
> -			ret = do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
> +			do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
>  				   3, 0xff, 0xff, 0);
> -			if (ret)
> -				return ret;
>  		}
>  
>  		/* test whether microscope is cradled */
> -- 
> 2.31.1
> 

This looks correct, I'll drop the revert.

But ick, recursion?  What could go wrong....

greg k-h