diff --git a/crates/fs-mistrust/src/imp.rs b/crates/fs-mistrust/src/imp.rs
index fb89b3903..3e0c5119c 100644
--- a/crates/fs-mistrust/src/imp.rs
+++ b/crates/fs-mistrust/src/imp.rs
@@ -196,8 +196,6 @@ impl<'a> super::Verifier<'a> {
             return;
         }
 
-        // mut not used when compiling or iOS
-        #[allow(unused_mut)]
         let mut forbidden_bits = if !self.readable_okay && path_type == PathType::Final {
             // If this is the target object, and it must not be readable, then
             // we forbid it to be group-rwx and all-rwx.
@@ -232,6 +230,13 @@ impl<'a> super::Verifier<'a> {
             forbidden_bits &= !0o070;
         }
 
+        // rational: on iOS the platform already protect user data, and not setting this poses
+        // issue with the default application data folder.
+        #[cfg(target_os = "ios")]
+        {
+            forbidden_bits &= !0o070;
+        }
+
         let bad_bits = meta.mode() & forbidden_bits;
         if bad_bits != 0 {
             errors.push(Error::BadPermission(
diff --git a/crates/tor-circmgr/src/mgr.rs b/crates/tor-circmgr/src/mgr.rs
index e9306800d..2033c9013 100644
--- a/crates/tor-circmgr/src/mgr.rs
+++ b/crates/tor-circmgr/src/mgr.rs
@@ -1325,16 +1325,18 @@ impl<B: AbstractCircBuilder + 'static, R: Runtime> AbstractCircMgr<B, R> {
     /// no longer be given out for new circuits.
     pub(crate) fn expire_circs(&self, now: Instant) {
         let mut list = self.circs.lock().expect("poisoned lock");
-        let dirty_cutoff = now - self.circuit_timing().max_dirtiness;
-        list.expire_circs(now, dirty_cutoff);
+        if let Some(dirty_cutoff) = now.checked_sub(self.circuit_timing().max_dirtiness) {
+            list.expire_circs(now, dirty_cutoff);
+        }
     }
 
     /// Consider expiring the circuit with given circuit `id`,
     /// according to the rules in `config` and the current time `now`.
     pub(crate) fn expire_circ(&self, circ_id: &<B::Circ as AbstractCirc>::Id, now: Instant) {
         let mut list = self.circs.lock().expect("poisoned lock");
-        let dirty_cutoff = now - self.circuit_timing().max_dirtiness;
-        list.expire_circ(circ_id, now, dirty_cutoff);
+        if let Some(dirty_cutoff) = now.checked_sub(self.circuit_timing().max_dirtiness) {
+            list.expire_circ(circ_id, now, dirty_cutoff);
+        }
     }
 
     /// Return the number of open circuits held by this circuit manager.
diff --git a/crates/tor-guardmgr/src/skew.rs b/crates/tor-guardmgr/src/skew.rs
index d81c6b08f..2d4bb32a2 100644
--- a/crates/tor-guardmgr/src/skew.rs
+++ b/crates/tor-guardmgr/src/skew.rs
@@ -22,9 +22,9 @@ pub(crate) struct SkewObservation {
 
 impl SkewObservation {
     /// Return true if this observation has been made more recently than
-    /// `cutoff`.
-    pub(crate) fn more_recent_than(&self, cutoff: Instant) -> bool {
-        self.when > cutoff
+    /// `cutoff`. If cutoff is None, consider it's very far in the past.
+    pub(crate) fn more_recent_than(&self, cutoff: Option<Instant>) -> bool {
+        cutoff.map_or(true, |cutoff| self.when > cutoff)
     }
 }
 
@@ -108,7 +108,7 @@ impl SkewEstimate {
         now: Instant,
     ) -> Option<Self> {
         // Only consider skew observations reported at least this recently.
-        let cutoff = now - Duration::from_secs(3600);
+        let cutoff = now.checked_sub(Duration::from_secs(3600));
 
         // Don't even look at our observations unless we  have at least this
         // many. (This value is chosen somewhat arbitrarily.)