tor-browser

commit 1984fd7905bb11bd4ed2fb0357134ab5aa309a8c
parent 12e4d8e30af263d4dad847a17fae817eace6887a
Author: Valentin Gosu <valentin.gosu@gmail.com>
Date:   Wed, 19 Nov 2025 12:32:55 +0000

Bug 1996813 - Change network.trr.retry_on_recoverable_errors to false and cycle connections when confirmation fails r=necko-reviewers,kershaw

This change does the following:
- Sets network.trr.retry_on_recoverable_errors to false, which means that failed TRR requests immediately fallback to native in mode 2.
- Makes it so a failed confirmation will trigger the use of a new connection for the next confirmation
- Triggers a confirmation for every TRR failure

Differential Revision: https://phabricator.services.mozilla.com/D273190

Diffstat:
M
modules/libpref/init/StaticPrefList.yaml
 | 
2
+-
M
netwerk/dns/TRRService.cpp
 | 
11
++++++++---
M
netwerk/dns/nsHostResolver.cpp
 | 
3
+++

3 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
@@ -14756,7 +14756,7 @@
 # If true, retry TRR for recoverable errors once.
 - name: network.trr.retry_on_recoverable_errors
   type: RelaxedAtomicBool
-  value: true
+  value: false
   mirror: always
 
 # If true, don't fallback to native DNS upon network errors.
diff --git a/netwerk/dns/TRRService.cpp b/netwerk/dns/TRRService.cpp
@@ -671,6 +671,7 @@ void TRRService::RebuildSuffixList(nsTArray<nsCString>&& aSuffixList) {
 
 void TRRService::ConfirmationContext::SetState(
     enum ConfirmationState aNewState) {
+  LOG(("ConfirmationContext::SetState %u", uint32_t(aNewState)));
   mState = aNewState;
 
   enum ConfirmationState state = mState;
@@ -802,9 +803,11 @@ bool TRRService::ConfirmationContext::HandleEvent(ConfirmationEvent aEvent,
 
     MOZ_ASSERT(mode == nsIDNSService::MODE_TRRFIRST,
                "Should only confirm in TRR first mode");
-    // Set aUseFreshConnection if TRR lookups are retried.
+    // Set aUseFreshConnection if TRR lookups are retried
+    // or if confirmation already failed.
     mTask = new TRR(service, service->mConfirmationNS, TRRTYPE_NS, ""_ns, false,
-                    StaticPrefs::network_trr_retry_on_recoverable_errors());
+                    mState == CONFIRM_TRYING_FAILED ||
+                        StaticPrefs::network_trr_retry_on_recoverable_errors());
     mTask->SetTimeout(StaticPrefs::network_trr_confirmation_timeout_ms());
     mTask->SetPurpose(TRR::Confirmation);
 
@@ -870,6 +873,8 @@ bool TRRService::ConfirmationContext::HandleEvent(ConfirmationEvent aEvent,
       }
       break;
     case ConfirmationEvent::ConfirmOK:
+      // Reset confirmation retry timeout to default
+      mRetryInterval = StaticPrefs::network_trr_retry_timeout_ms();
       SetState(CONFIRM_OK);
       mTask = nullptr;
       break;
@@ -879,7 +884,7 @@ bool TRRService::ConfirmationContext::HandleEvent(ConfirmationEvent aEvent,
       SetState(CONFIRM_FAILED);
       mTask = nullptr;
       // retry failed NS confirmation
-
+      LOG(("Setting timer to reconfirm %u", uint32_t(mRetryInterval)));
       NS_NewTimerWithCallback(getter_AddRefs(mTimer), this, mRetryInterval,
                               nsITimer::TYPE_ONE_SHOT);
       // double the interval up to this point
diff --git a/netwerk/dns/nsHostResolver.cpp b/netwerk/dns/nsHostResolver.cpp
@@ -1381,6 +1381,9 @@ bool nsHostResolver::MaybeRetryTRRLookup(
   MOZ_ASSERT(!aAddrRec->mResolving);
   if (!StaticPrefs::network_trr_retry_on_recoverable_errors()) {
     LOG(("nsHostResolver::MaybeRetryTRRLookup retrying with native"));
+
+    // Trigger a confirmation retry, in order to cycle connection if needed
+    TRRService::Get()->RetryTRRConfirm();
     return NS_SUCCEEDED(NativeLookup(aAddrRec, aLock));
   }