bnxt_en: Refactor coredump functions

The coredump functionality will be used by devlink health. Refactor
these functions that get coredump and coredump length. There is no
functional change, but the following checkpatch warnings were
addressed:

  - strscpy is preferred over strlcpy.
  - sscanf results should be checked, with an additional warning.
Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c

@@ -3808,7 +3808,7 @@ bnxt_fill_coredump_record(struct bnxt *bp, struct bnxt_coredump_record *record,
 	record->low_version = 0;
 	record->high_version = 1;
 	record->asic_state = 0;
-	strlcpy(record->system_name, utsname()->nodename,
+	strscpy(record->system_name, utsname()->nodename,
 		sizeof(record->system_name));
 	record->year = cpu_to_le16(tm.tm_year + 1900);
 	record->month = cpu_to_le16(tm.tm_mon + 1);
@@ -3820,11 +3820,12 @@ bnxt_fill_coredump_record(struct bnxt *bp, struct bnxt_coredump_record *record,
 	strcpy(record->commandline, "ethtool -w");
 	record->total_segments = cpu_to_le32(total_segs);
 
-	sscanf(utsname()->release, "%u.%u", &os_ver_major, &os_ver_minor);
+	if (sscanf(utsname()->release, "%u.%u", &os_ver_major, &os_ver_minor) != 2)
+		netdev_warn(bp->dev, "Unknown OS release in coredump\n");
 	record->os_ver_major = cpu_to_le32(os_ver_major);
 	record->os_ver_minor = cpu_to_le32(os_ver_minor);
 
-	strlcpy(record->os_name, utsname()->sysname, 32);
+	strscpy(record->os_name, utsname()->sysname, sizeof(record->os_name));
 	time64_to_tm(end, 0, &tm);
 	record->end_year = cpu_to_le16(tm.tm_year + 1900);
 	record->end_month = cpu_to_le16(tm.tm_mon + 1);
@@ -3842,7 +3843,7 @@ bnxt_fill_coredump_record(struct bnxt *bp, struct bnxt_coredump_record *record,
 	record->ioctl_high_version = 0;
 }
 
-static int bnxt_get_coredump(struct bnxt *bp, void *buf, u32 *dump_len)
+static int __bnxt_get_coredump(struct bnxt *bp, void *buf, u32 *dump_len)
 {
 	u32 ver_get_resp_len = sizeof(struct hwrm_ver_get_output);
 	u32 offset = 0, seg_hdr_len, seg_record_len, buf_len = 0;
@@ -3945,6 +3946,30 @@ static int bnxt_get_coredump(struct bnxt *bp, void *buf, u32 *dump_len)
 	return rc;
 }
 
+static int bnxt_get_coredump(struct bnxt *bp, u16 dump_type, void *buf, u32 *dump_len)
+{
+	if (dump_type == BNXT_DUMP_CRASH) {
+#ifdef CONFIG_TEE_BNXT_FW
+		return tee_bnxt_copy_coredump(buf, 0, *dump_len);
+#else
+		return -EOPNOTSUPP;
+#endif
+	} else {
+		return __bnxt_get_coredump(bp, buf, dump_len);
+	}
+}
+
+static u32 bnxt_get_coredump_length(struct bnxt *bp, u16 dump_type)
+{
+	u32 len = 0;
+
+	if (dump_type == BNXT_DUMP_CRASH)
+		len = BNXT_CRASH_DUMP_LEN;
+	else
+		__bnxt_get_coredump(bp, NULL, &len);
+	return len;
+}
+
 static int bnxt_set_dump(struct net_device *dev, struct ethtool_dump *dump)
 {
 	struct bnxt *bp = netdev_priv(dev);
@@ -3976,10 +4001,7 @@ static int bnxt_get_dump_flag(struct net_device *dev, struct ethtool_dump *dump)
 			bp->ver_resp.hwrm_fw_rsvd_8b;
 
 	dump->flag = bp->dump_flag;
-	if (bp->dump_flag == BNXT_DUMP_CRASH)
-		dump->len = BNXT_CRASH_DUMP_LEN;
-	else
-		bnxt_get_coredump(bp, NULL, &dump->len);
+	dump->len = bnxt_get_coredump_length(bp, bp->dump_flag);
 	return 0;
 }
 
@@ -3994,15 +4016,7 @@ static int bnxt_get_dump_data(struct net_device *dev, struct ethtool_dump *dump,
 	memset(buf, 0, dump->len);
 
 	dump->flag = bp->dump_flag;
-	if (dump->flag == BNXT_DUMP_CRASH) {
-#ifdef CONFIG_TEE_BNXT_FW
-		return tee_bnxt_copy_coredump(buf, 0, dump->len);
-#endif
-	} else {
-		return bnxt_get_coredump(bp, buf, &dump->len);
-	}
-
-	return 0;
+	return bnxt_get_coredump(bp, dump->flag, buf, &dump->len);
 }
 
 static int bnxt_get_ts_info(struct net_device *dev,