RDMA clang warning fixes

From: Leon Romanovsky <[email protected]>

This is followup to Stephen's series [1].

Thanks

[1] https://lore.kernel.org/all/[email protected]

Leon Romanovsky (2):
rdma: Limit copy data by the destination size
rdma: Don't allocate sparse array

 rdma/res-srq.c | 14 +++++---------
 rdma/res.c     |  6 +++---
 2 files changed, 8 insertions(+), 12 deletions(-)

2.33.1

From: Leon Romanovsky <[email protected]>

The strncat() function will copy upto n bytes supplied as third argument. The n bytes shouldn't be no more than destination and not the source.

This change fixes the following clang compilation warnings:

res-srq.c:75:25: warning: size argument in 'strncat' call appears to be size of the source [-Wstrncat-size]

                        strncat(qp_str, tmp, sizeof(tmp) - 1);
                                             ^~~~~~~~~~~~~~~
res-srq.c:99:23: warning: size argument in 'strncat' call appears to be size of the source [-Wstrncat-size]
        strncat(qp_str, tmp, sizeof(tmp) - 1);
                             ^~~~~~~~~~~~~~~
res-srq.c:142:25: warning: size argument in 'strncat' call appears to be size of the source [-Wstrncat-size]
                        strncat(qp_str, tmp, sizeof(tmp) - 1);
                                             ^~~~~~~~~~~~~~~

---
 rdma/res-srq.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

index 5d8f3842..3038c352 100644
@@ -70,9 +70,8 @@ static int filter_srq_range_qps(struct rd *rd, struct nlattr **qp_line,
 					 *delimiter, tmp_min_range,
 					 tmp_max_range);
 
-			if (strlen(qp_str) + strlen(tmp) >= MAX_QP_STR_LEN)
-				return -EINVAL;
-			strncat(qp_str, tmp, sizeof(tmp) - 1);
+			strncat(qp_str, tmp,
+				MAX_QP_STR_LEN - strlen(qp_str) - 1);
 
 			memset(tmp, 0, strlen(tmp));
 			*delimiter = ",";

@@ -94,9 +93,7 @@ static int filter_srq_range_qps(struct rd *rd, struct nlattr **qp_line,
 		snprintf(tmp, sizeof(tmp), "%s%d-%d", *delimiter,
 			 tmp_min_range, tmp_max_range);
 
-	if (strlen(qp_str) + strlen(tmp) >= MAX_QP_STR_LEN)
-		return -EINVAL;
-	strncat(qp_str, tmp, sizeof(tmp) - 1);
+	strncat(qp_str, tmp, MAX_QP_STR_LEN - strlen(qp_str) - 1);
 	*delimiter = ",";
 	return 0;
 }

@@ -137,9 +134,8 @@ static int get_srq_qps(struct rd *rd, struct nlattr *qp_table,  char *qp_str)
 					qp_line[RDMA_NLDEV_ATTR_RES_LQPN]))
 				continue;
 			snprintf(tmp, sizeof(tmp), "%s%d", delimiter, qpn);
-			if (strlen(qp_str) + strlen(tmp) >= MAX_QP_STR_LEN)
-				goto out;
-			strncat(qp_str, tmp, sizeof(tmp) - 1);
+			strncat(qp_str, tmp,
+				MAX_QP_STR_LEN - strlen(qp_str) - 1);
 			delimiter = ",";
 		} else if (qp_line[RDMA_NLDEV_ATTR_MIN_RANGE] &&
 			   qp_line[RDMA_NLDEV_ATTR_MAX_RANGE]) {

2.33.1

From: Leon Romanovsky <[email protected]>

The addition of driver QP type with index 0xFF caused to the following clang compilation error:

res.c:152:10: warning: result of comparison of constant 256 with expression of type 'uint8_t' (aka 'unsigned char') is always true [-Wtautological-constant-out-of-range-compare]

        if (idx < ARRAY_SIZE(qp_types_str) && qp_types_str[idx])
            ~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~

Instead of allocating very sparse array, simply create separate check for the driver QP type.

---
 rdma/res.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

index 9aae5d4b..21fef9bd 100644
@@ -146,12 +146,12 @@ const char *qp_types_to_str(uint8_t idx)
 						     "RAW_ETHERTYPE",
 						     "UNKNOWN", "RAW_PACKET",
 						     "XRC_INI", "XRC_TGT",
-						     [0xFF] = "DRIVER",
 	};
 
-	if (idx < ARRAY_SIZE(qp_types_str) && qp_types_str[idx])
+	if (idx < ARRAY_SIZE(qp_types_str))
 		return qp_types_str[idx];
-	return "UNKNOWN";
+
+	return (idx == 0xFF) ? "DRIVER" : "UNKNOWN";
 }
 
 void print_comm(struct rd *rd, const char *str, struct nlattr **nla_line)

2.33.1