On Tue, Aug 11, 2020 at 08:15:05AM -0700, trix@xxxxxxxxxx wrote:
> From: Tom Rix <trix@xxxxxxxxxx>
>
> clang static analysis reports this representative problem
>
> realtek_cr.c:639:3: warning: The left expression of the compound
> assignment is an uninitialized value. The computed value will
> also be garbage
> SET_BIT(value, 2);
> ^~~~~~~~~~~~~~~~~
>
> value is set by a successful call to rts51x_read_mem()
>
> retval = rts51x_read_mem(us, 0xFE77, &value, 1);
> if (retval < 0)
> return -EIO;
>
> A successful call to rts51x_read_mem returns 0, failure can
> return positive and negative values. This check is wrong
> for a number of functions. Fix the retval check.
>
> Fixes: 065e60964e29 ("ums_realtek: do not use stack memory for DMA")
> Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
> ---
> drivers/usb/storage/realtek_cr.c | 36 ++++++++++++++++----------------
> 1 file changed, 18 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/usb/storage/realtek_cr.c b/drivers/usb/storage/realtek_cr.c
> index 3789698d9d3c..b983753e2368 100644
> --- a/drivers/usb/storage/realtek_cr.c
> +++ b/drivers/usb/storage/realtek_cr.c
> @@ -481,16 +481,16 @@ static int enable_oscillator(struct us_data *us)
> u8 value;
>
> retval = rts51x_read_mem(us, 0xFE77, &value, 1);
> - if (retval < 0)
> + if (retval != STATUS_SUCCESS)
> return -EIO;
Instead of changing all these call sites, wouldn't it be a lot easier
just to change rts51x_read_mem() to make it always return a negative
value (such as -EIO) when there's an error?
Alan Stern
