Re: [PATCH 7/7] Revert "serial: max310x: pass return value of spi_register_driver"

[Greg Kroah-Hartman]

On Thu, Apr 29, 2021 at 03:08:11PM +0200, Greg Kroah-Hartman wrote:
> This reverts commit 51f689cc11333944c7a457f25ec75fcb41e99410.
> 
> 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 submitted to 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) but later
> withdrawn.
> 
> 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>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/tty/serial/max310x.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
> index 8534d6e45a1d..a3ba0e6520a1 100644
> --- a/drivers/tty/serial/max310x.c
> +++ b/drivers/tty/serial/max310x.c
> @@ -1518,10 +1518,10 @@ static int __init max310x_uart_init(void)
>  		return ret;
>  
>  #ifdef CONFIG_SPI_MASTER
> -	ret = spi_register_driver(&max310x_spi_driver);
> +	spi_register_driver(&max310x_spi_driver);
>  #endif
>  
> -	return ret;
> +	return 0;
>  }
>  module_init(max310x_uart_init);
>  
> -- 
> 2.31.1
> 

This is incorrect because if spi_register_driver fails, the uart needs
to be properly unregistered before the module is unloaded automatically,
causing a crash.

I'll keep the revert and fix this up properly.

thanks,

greg k-h