On 10/25/2018 9:31 AM, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> In the expression "utx_len << 28", utx_len starts as u8, but is promoted
> to a signed int, then sign-extended to u64. If utx_len is 0xf8 or greater
> then the sign extension will set all the upper bits of utx_cmd which is
> probably not what was intended. Cast to utx_len to u64 to avoid the sign
> extension.
>
> Detected by CoverityScan, CID#138764 ("Unintended sign extension")
>
> Fixes: b038ced7b370 ("RDMA/cxgb3: Add driver for Chelsio T3 RNIC")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> drivers/infiniband/hw/cxgb3/cxio_hal.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/hw/cxgb3/cxio_hal.c b/drivers/infiniband/hw/cxgb3/cxio_hal.c
> index dcb4bba522ba..c5cb80ccc6d6 100644
> --- a/drivers/infiniband/hw/cxgb3/cxio_hal.c
> +++ b/drivers/infiniband/hw/cxgb3/cxio_hal.c
> @@ -647,7 +647,7 @@ static int cxio_hal_ctrl_qp_write_mem(struct cxio_rdev *rdev_p, u32 addr,
> wqe += (sizeof(struct t3_bypass_wr) >> 3);
> utx_cmd = (T3_UTX_MEM_WRITE << 28) | (addr + i * 3);
> utx_cmd <<= 32;
> - utx_cmd |= (utx_len << 28) | ((utx_len << 2) + 1);
> + utx_cmd |= ((u64)utx_len << 28) | ((utx_len << 2) + 1);
> *wqe = cpu_to_be64(utx_cmd);
> wqe++;
> copy_data = (u8 *) data + i * 96;
>
Acked-by: Steve Wise <swise@xxxxxxxxxxx>
