Sanitize UTF-8 in dmi collector (#2229)

Replace invalid UTF-8 chars with "�" string.

Fixes: https://github.com/prometheus/node_exporter/issues/2228

Signed-off-by: Ben Kochie <superq@gmail.com>

CHANGELOG.md

@@ -5,7 +5,9 @@
 * [ENHANCEMENT]
 * [BUGFIX]
 
+* [ENHANCEMENT] Add node_softirqs_total metric #2221
 * [BUGFIX] Handle nil CPU thermal power status on M1 #2218
+* [BUGFIX] Sanitize UTF-8 in dmi collector #2229
 
 ## 1.3.0 / 2021-10-20
 

collector/dmi.go

@@ -20,6 +20,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"strings"
 
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
@@ -78,7 +79,7 @@ func NewDMICollector(logger log.Logger) (Collector, error) {
 	} {
 		if value != nil {
 			labels = append(labels, label)
-			values = append(values, *value)
+			values = append(values, strings.ToValidUTF8(*value, "<EFBFBD>"))
 		}
 	}
 

collector/fixtures/e2e-output.txt

@@ -609,7 +609,7 @@ node_disk_written_bytes_total{device="sr0"} 0
 node_disk_written_bytes_total{device="vda"} 1.0938236928e+11
 # HELP node_dmi_info A metric with a constant '1' value labeled by bios_date, bios_release, bios_vendor, bios_version, board_asset_tag, board_name, board_serial, board_vendor, board_version, chassis_asset_tag, chassis_serial, chassis_vendor, chassis_version, product_family, product_name, product_serial, product_sku, product_uuid, product_version, system_vendor if provided by DMI.
 # TYPE node_dmi_info gauge
-node_dmi_info{bios_date="04/12/2021",bios_release="2.2",bios_vendor="Dell Inc.",bios_version="2.2.4",board_name="07PXPY",board_serial=".7N62AI2.GRTCL6944100GP.",board_vendor="Dell Inc.",board_version="A01",chassis_asset_tag="",chassis_serial="7N62AI2",chassis_vendor="Dell Inc.",chassis_version="",product_family="PowerEdge",product_name="PowerEdge R6515",product_serial="7N62AI2",product_sku="SKU=NotProvided;ModelName=PowerEdge R6515",product_uuid="83340ca8-cb49-4474-8c29-d2088ca84dd9",product_version="",system_vendor="Dell Inc."} 1
+node_dmi_info{bios_date="04/12/2021",bios_release="2.2",bios_vendor="Dell Inc.",bios_version="2.2.4",board_name="07PXPY",board_serial=".7N62AI2.GRTCL6944100GP.",board_vendor="Dell Inc.",board_version="A01",chassis_asset_tag="",chassis_serial="7N62AI2",chassis_vendor="Dell Inc.",chassis_version="",product_family="PowerEdge",product_name="PowerEdge R6515",product_serial="7N62AI2",product_sku="SKU=NotProvided;ModelName=PowerEdge R6515",product_uuid="83340ca8-cb49-4474-8c29-d2088ca84dd9",product_version="<EFBFBD>[<EFBFBD>",system_vendor="Dell Inc."} 1
 # HELP node_drbd_activitylog_writes_total Number of updates of the activity log area of the meta data.
 # TYPE node_drbd_activitylog_writes_total counter
 node_drbd_activitylog_writes_total{device="drbd1"} 1100

collector/fixtures/sys.ttar

@@ -141,7 +141,7 @@ Mode: 400
 # ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 Path: sys/class/dmi/id/product_version
 Lines: 1
-
+<EFBFBD>[<EFBFBD>
 Mode: 444
 # ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 Path: sys/class/dmi/id/sys_vendor

end-to-end-test.sh

@@ -11,6 +11,7 @@ enabled_collectors=$(cat << COLLECTORS
   cpu
   cpufreq
   diskstats
+  dmi
   drbd
   edac
   entropy