Hello Aviv Heller,
The patch fadd59fc50d0: "net/mlx5: Introduce inter-device
communication mechanism" from Dec 4, 2018, leads to the following
static checker warning:
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:246 mlx5_devcom_get_peer_data()
warn: potential off by one (named limit 'MLX5_MAX_PORTS') 'comp->device[i]'
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
226 void *mlx5_devcom_get_peer_data(struct mlx5_devcom *devcom,
227 enum mlx5_devcom_components id)
228 {
229 struct mlx5_devcom_component *comp;
230 int i;
231
232 if (IS_ERR_OR_NULL(devcom))
233 return NULL;
234
235 comp = &devcom->priv->components[id];
236 down_read(&comp->sem);
237 if (!comp->paired) {
238 up_read(&comp->sem);
239 return NULL;
240 }
241
242 for (i = 0; i < MLX5_MAX_PORTS; i++)
243 if (i != devcom->idx)
^^^^^^^^^^^^^^^^
244 break;
245
--> 246 return comp->device[i].data;
Smatch thinks that "i" can be MLX5_MAX_PORTS but, of course, it can't.
I don't really understand the loop. It's the equivalent of saying:
return comp->device[(devcom->idx == 0) ? 1 : 0].data;
247 }
regards,
dan carpenter
