Add missing SAFETY docs

src/components/proxy/io_uring_shared.rs

@@ -465,6 +465,8 @@ impl<'uring> LoopCtx<'uring> {
             self.sq.sync();
 
             match self.backlog.pop_front() {
+                // SAFETY: Same as Self::push, all memory pointed to in our ops are pinned at
+                // stable locations in memory
                 Some(sqe) => unsafe {
                     let _ = self.sq.push(&sqe);
                 },

src/components/proxy/sessions/inner_metrics.rs

@@ -41,6 +41,7 @@ pub(crate) fn active_sessions(asn: Option<&crate::net::maxmind_db::IpNetEntry>)
         let len = crate::metrics::itoa(asnfo.id, &mut asn);
 
         ACTIVE_SESSIONS.with_label_values(&[
+            // SAFETY: itoa only writes ASCII
             unsafe { std::str::from_utf8_unchecked(&asn[..len as _]) },
             &asnfo.as_name,
             &asnfo.as_cc,

src/metrics.rs

@@ -86,6 +86,7 @@ pub struct AsnInfo<'a> {
 impl<'a> AsnInfo<'a> {
     #[inline]
     fn asn_str(&self) -> &str {
+        // SAFETY: we only write ASCII in itoa
         unsafe { std::str::from_utf8_unchecked(&self.asn[..self.asn_len as _]) }
     }
 }

src/pool.rs

@@ -197,6 +197,8 @@ impl PoolBuffer {
     #[inline]
     #[cfg(target_os = "linux")]
     pub(crate) fn set_len(&mut self, len: usize) {
+        // SAFETY: len is the length as returned from the kernel on a successful
+        // recv_from call
         unsafe { self.inner.set_len(len) }
     }
 }