From: Florian Forster <octo@collectd.org>
Date: Fri, 12 Oct 2018 11:18:42 +0000 (+0200)
Subject: disk plugin: Support Linux kernels with additional fields.
X-Git-Url: https://git.octo.it/?p=collectd.git;a=commitdiff_plain;h=6ce52f70cc1e6450df3454f19743a29295b84050

disk plugin: Support Linux kernels with additional fields.

Linux 4.19 will add additional counters, which caused this plugin to
bail out because it checked the number of fields exactly instead of
ensuring that there are *at least* the number of fields expected.

Fixes: #2951
---

diff --git a/src/disk.c b/src/disk.c
index e01e1506..cfda6351 100644
--- a/src/disk.c
+++ b/src/disk.c
@@ -695,7 +695,9 @@ static int disk_read(void) {
 
     numfields = strsplit(buffer, fields, 32);
 
-    if ((numfields != (14 + fieldshift)) && (numfields != 7))
+    /* need either 7 fields (partition)
+     * or at least 14 fields (15 on Linux 2.4) */
+    if ((numfields != 7) && (numfields < (14 + fieldshift)))
       continue;
 
     minor = atoll(fields[1]);
@@ -729,7 +731,8 @@ static int disk_read(void) {
       read_sectors = atoll(fields[4]);
       write_ops = atoll(fields[5]);
       write_sectors = atoll(fields[6]);
-    } else if (numfields == (14 + fieldshift)) {
+    } else {
+      assert(numfields >= (14 + fieldshift));
       read_ops = atoll(fields[3 + fieldshift]);
       write_ops = atoll(fields[7 + fieldshift]);
 
@@ -748,9 +751,6 @@ static int disk_read(void) {
         io_time = atof(fields[12 + fieldshift]);
         weighted_time = atof(fields[13 + fieldshift]);
       }
-    } else {
-      DEBUG("numfields = %i; => unknown file format.", numfields);
-      continue;
     }
 
     {