tor-browser

commit 9992d3f9eec03a041b86b8350643866de228dffb
parent d4b00c50c4c436125e3bbd3f8c1ba666d0892768
Author: Dan Baker <dbaker@mozilla.com>
Date:   Thu, 23 Oct 2025 15:29:29 -0600

Bug 1995393 - Vendor libwebrtc from 3d4bae08b2

Upstream commit: https://webrtc.googlesource.com/src/+/3d4bae08b2b44835ab25612e0cd60e2aff982b1e
    SDP munging: Isolate candidate-count changes

    Bug: webrtc:414284082
    Change-Id: Iaac30a31d4f6b85613826158056ba6d3f14449a8
    Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/404420
    Commit-Queue: Harald Alvestrand <hta@webrtc.org>
    Auto-Submit: Harald Alvestrand <hta@webrtc.org>
    Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
    Cr-Commit-Position: refs/heads/main@{#45343}

Diffstat:
M
third_party/libwebrtc/README.mozilla.last-vendor
 | 
4
++--
M
third_party/libwebrtc/api/uma_metrics.h
 | 
1
+
M
third_party/libwebrtc/moz-patch-stack/p0002.patch
 | 
2
+-
M
third_party/libwebrtc/pc/sdp_munging_detector.cc
 | 
16
++++++++++++++++
M
third_party/libwebrtc/pc/sdp_munging_detector_unittest.cc
 | 
16
++++++++++++++++

5 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/third_party/libwebrtc/README.mozilla.last-vendor b/third_party/libwebrtc/README.mozilla.last-vendor
@@ -1,4 +1,4 @@
 # ./mach python dom/media/webrtc/third_party_build/vendor-libwebrtc.py --from-local /Users/danielbaker/elm/.moz-fast-forward/moz-libwebrtc --commit mozpatches libwebrtc
-libwebrtc updated from /Users/danielbaker/elm/.moz-fast-forward/moz-libwebrtc commit mozpatches on 2025-10-23T21:26:32.804291+00:00.
+libwebrtc updated from /Users/danielbaker/elm/.moz-fast-forward/moz-libwebrtc commit mozpatches on 2025-10-23T21:29:17.819152+00:00.
 # base of lastest vendoring
-9ebd1ce74d
+3d4bae08b2
diff --git a/third_party/libwebrtc/api/uma_metrics.h b/third_party/libwebrtc/api/uma_metrics.h
@@ -199,6 +199,7 @@ enum SdpMungingType {
   kDirection = 29,
   kRtcpMux = 30,
   kIceOptionsTrickle = 31,
+  kIceCandidateCount = 32,
   // RTP header extension munging.
   kRtpHeaderExtensionRemoved = 40,
   kRtpHeaderExtensionAdded = 41,
diff --git a/third_party/libwebrtc/moz-patch-stack/p0002.patch b/third_party/libwebrtc/moz-patch-stack/p0002.patch
@@ -26,7 +26,7 @@ Cr-Branched-From: 9bd64751d9b3b35a820cb72c9029993e218146a1-refs/heads/main@{#452
  1 file changed, 6 insertions(+)
 
 diff --git a/pc/sdp_munging_detector.cc b/pc/sdp_munging_detector.cc
-index 58e580baa3..7b126d9b26 100644
+index 04f0d53fd0..88f38da30d 100644
 --- a/pc/sdp_munging_detector.cc
 +++ b/pc/sdp_munging_detector.cc
 @@ -427,6 +427,12 @@ SdpMungingType DetermineSdpMungingType(
diff --git a/third_party/libwebrtc/pc/sdp_munging_detector.cc b/third_party/libwebrtc/pc/sdp_munging_detector.cc
@@ -559,6 +559,22 @@ SdpMungingType DetermineSdpMungingType(
     return type;
   }
 
+  // Validate number of candidates.
+  for (size_t content_index = 0; content_index < last_created_contents.size();
+       content_index++) {
+    // All contents have a (possibly empty) candidate set.
+    // Check that this holds.
+    RTC_DCHECK(sdesc->candidates(content_index));
+    if (sdesc->candidates(content_index)->count() !=
+        last_created_desc->candidates(content_index)->count()) {
+      RTC_LOG(LS_WARNING)
+          << "SDP munging: media section " << content_index << " changed from "
+          << last_created_desc->candidates(content_index)->count() << " to "
+          << sdesc->candidates(content_index)->count() << " candidates";
+      return SdpMungingType::kIceCandidateCount;
+    }
+  }
+
   // TODO: crbug.com/40567530 - this serializes the descriptions back to a SDP
   // string which is very complex and we not should be be forced to rely on
   // string equality.
diff --git a/third_party/libwebrtc/pc/sdp_munging_detector_unittest.cc b/third_party/libwebrtc/pc/sdp_munging_detector_unittest.cc
@@ -26,6 +26,7 @@
 #include "api/audio_codecs/audio_format.h"
 #include "api/audio_codecs/builtin_audio_decoder_factory.h"
 #include "api/audio_codecs/builtin_audio_encoder_factory.h"
+#include "api/candidate.h"
 #include "api/create_peerconnection_factory.h"
 #include "api/jsep.h"
 #include "api/media_types.h"
@@ -1427,4 +1428,19 @@ TEST_F(SdpMungingTest, VideoCodecsRtcpReducedSize) {
       ElementsAre(Pair(SdpMungingType::kVideoCodecsRtcpReducedSize, 1)));
 }
 
+TEST_F(SdpMungingTest, NumberOfCandidates) {
+  auto pc = CreatePeerConnection();
+  pc->AddVideoTrack("video_track", {});
+
+  std::unique_ptr<SessionDescriptionInterface> offer = pc->CreateOffer();
+  IceCandidate candidate("", 0, Candidate());
+  EXPECT_TRUE(offer->AddCandidate(&candidate));
+
+  RTCError error;
+  EXPECT_TRUE(pc->SetLocalDescription(std::move(offer), &error));
+  EXPECT_THAT(
+      metrics::Samples("WebRTC.PeerConnection.SdpMunging.Offer.Initial"),
+      ElementsAre(Pair(SdpMungingType::kIceCandidateCount, 1)));
+}
+
 }  // namespace webrtc