openpgp: Make iterating over maps of broken packages more robust.

  - Avoid out-of-bounds slicing.

1 files changed, 3 insertions, 2 deletions

diff --git a/openpgp/src/parse/parse.rs b/openpgp/src/parse/parse.rs
index 90865ff1..ebe78830 100644
--- a/openpgp/src/parse/parse.rs
+++ b/openpgp/src/parse/parse.rs
@@ -584,8 +584,9 @@ impl Map {
         Box::new(
             iter::once(("header", self.header.as_slice()))
                 .chain(self.entries.iter().map(move |e| {
-                    (e.field,
-                     &self.data[e.offset..cmp::min(len, e.offset + e.length)])
+                    let start = cmp::min(len, e.offset);
+                    let end = cmp::min(len, e.offset + e.length);
+                    (e.field, &self.data[start..end])
                 })))
     }
 }