Merge tag 'wireless-next-2024-01-03' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next

Johannes Berg says:

====================
Just a couple of more things over the holidays:

 - first kunit tests for both cfg80211 and mac80211
 - a few multi-link fixes
 - DSCP mapping update
 - RCU fix

* tag 'wireless-next-2024-01-03' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next:
  wifi: mac80211: remove redundant ML element check
  wifi: cfg80211: parse all ML elements in an ML probe response
  wifi: cfg80211: correct comment about MLD ID
  wifi: cfg80211: Update the default DSCP-to-UP mapping
  wifi: cfg80211: tests: add some scanning related tests
  wifi: mac80211: kunit: extend MFP tests
  wifi: mac80211: kunit: generalize public action test
  wifi: mac80211: add kunit tests for public action handling
  kunit: add a convenience allocation wrapper for SKBs
  kunit: add parameter generation macro using description from array
  wifi: mac80211: fix spelling typo in comment
  wifi: cfg80211: fix RCU dereference in __cfg80211_bss_update
====================

Link: https://lore.kernel.org/r/20240103144423.52269-3-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 626b858b4b35..d1ce3bee2797 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -980,7 +980,63 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb,
 		}
 	}
 
+	/* The default mapping as defined Section 2.3 in RFC8325: The three
+	 * Most Significant Bits (MSBs) of the DSCP are used as the
+	 * corresponding L2 markings.
+	 */
 	ret = dscp >> 5;
+
+	/* Handle specific DSCP values for which the default mapping (as
+	 * described above) doesn't adhere to the intended usage of the DSCP
+	 * value. See section 4 in RFC8325. Specifically, for the following
+	 * Diffserv Service Classes no update is needed:
+	 * - Standard: DF
+	 * - Low Priority Data: CS1
+	 * - Multimedia Streaming: AF31, AF32, AF33
+	 * - Multimedia Conferencing: AF41, AF42, AF43
+	 * - Network Control Traffic: CS7
+	 * - Real-Time Interactive: CS4
+	 */
+	switch (dscp >> 2) {
+	case 10:
+	case 12:
+	case 14:
+		/* High throughput data: AF11, AF12, AF13 */
+		ret = 0;
+		break;
+	case 16:
+		/* Operations, Administration, and Maintenance and Provisioning:
+		 * CS2
+		 */
+		ret = 0;
+		break;
+	case 18:
+	case 20:
+	case 22:
+		/* Low latency data: AF21, AF22, AF23 */
+		ret = 3;
+		break;
+	case 24:
+		/* Broadcasting video: CS3 */
+		ret = 4;
+		break;
+	case 40:
+		/* Signaling: CS5 */
+		ret = 5;
+		break;
+	case 44:
+		/* Voice Admit: VA */
+		ret = 6;
+		break;
+	case 46:
+		/* Telephony traffic: EF */
+		ret = 6;
+		break;
+	case 48:
+		/* Network Control Traffic: CS6 */
+		ret = 7;
+		break;
+	}
 out:
 	return array_index_nospec(ret, IEEE80211_NUM_TIDS);
 }