Ensure the adapter name 100% matching when parsing proc/net/dev (#92187)

* Ensure the adapter name 100% matching when parsing proc/net/dev

* Update src/libraries/System.Net.NetworkInformation/src/System/Net/NetworkInformation/StringParsingHelpers.Statistics.cs

Co-authored-by: Miha Zupan <[email protected]>

* Move the stackalloc out of the loop

* Update src/libraries/System.Net.NetworkInformation/src/System/Net/NetworkInformation/StringParsingHelpers.Statistics.cs

Co-authored-by: Miha Zupan <[email protected]>

---------

Co-authored-by: Miha Zupan <[email protected]>

Author: skyoxZ

src/libraries/System.Net.NetworkInformation/src/System/Net/NetworkInformation/StringParsingHelpers.Statistics.cs

@@ -407,15 +407,25 @@ internal static IPInterfaceStatisticsTable ParseInterfaceStatisticsTableFromFile
             {
                 sr.ReadLine();
                 sr.ReadLine();
-                int index = 0;
+                Span<Range> pieces = stackalloc Range[18]; // [0]-[16] used, +1 to ensure any additional segment goes into [17]
                 while (!sr.EndOfStream)
                 {
                     string line = sr.ReadLine()!;
                     if (line.Contains(name))
                     {
-                        Span<Range> pieces = stackalloc Range[18]; // [0] skipped, [1]-[16] used, +1 to ensure any additional segment goes into [17]
                         ReadOnlySpan<char> lineSpan = line;
-                        pieces = pieces.Slice(0, lineSpan.SplitAny(pieces, " :", StringSplitOptions.RemoveEmptyEntries));
+                        int pieceCount = lineSpan.SplitAny(pieces, " :", StringSplitOptions.RemoveEmptyEntries);
+
+                        if (pieceCount < 17)
+                        {
+                            continue;
+                        }
+
+                        if (!lineSpan[pieces[0]].SequenceEqual(name))
+                        {
+                            // The adapter name doesn't exactly match.
+                            continue;
+                        }
 
                         return new IPInterfaceStatisticsTable()
                         {
@@ -438,7 +448,6 @@ internal static IPInterfaceStatisticsTable ParseInterfaceStatisticsTableFromFile
                             CompressedPacketsTransmitted = ParseUInt64AndClampToInt64(lineSpan[pieces[16]]),
                         };
                     }
-                    index += 1;
                 }
 
                 throw ExceptionHelper.CreateForParseFailure();

src/libraries/System.Net.NetworkInformation/tests/FunctionalTests/NetworkFiles/dev

@@ -1,4 +1,5 @@
 Inter-|   Receive                                                |  Transmit
  face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed
+wlan0a:   20000     394    2    4    6     8         10        12    429496730000     208    1    2    3     4       5          6
  wlan0:   26622     394    2    4    6     8         10        12    429496730000     208    1    2    3     4       5          6
     lo:   18446744073709551615     302    0    0    0     0          0         0    30008     302    0    0    0     0       0          0