diff --git a/src/rustup-dist/src/component/package.rs b/src/rustup-dist/src/component/package.rs
index 3326231ab0..8aa63db97a 100644
--- a/src/rustup-dist/src/component/package.rs
+++ b/src/rustup-dist/src/component/package.rs
@@ -123,10 +123,16 @@ impl Package for DirectoryPackage {
 // but due to rust-lang/rust#25479 they don't.
 #[cfg(unix)]
 fn set_file_perms(dest_path: &Path, src_path: &Path) -> Result<()> {
-    use std::fs;
+    use std::fs::{self, Metadata};
     use std::os::unix::fs::PermissionsExt;
     use walkdir::WalkDir;
 
+    // Compute whether this entry needs the X bit
+    fn needs_x(meta: &Metadata) -> bool {
+        meta.is_dir() || // Directories need it
+        meta.permissions().mode() & 0o700 == 0o700 // If it is rwx for the user, it gets the X bit
+    }
+
     // By convention, anything in the bin/ directory of the package is a binary
     let is_bin = if let Some(p) = src_path.parent() {
         p.ends_with("bin")
@@ -141,25 +147,14 @@ fn set_file_perms(dest_path: &Path, src_path: &Path) -> Result<()> {
         for entry in WalkDir::new(dest_path) {
             let entry = try!(entry.chain_err(|| ErrorKind::ComponentDirPermissionsFailed));
             let meta = try!(entry.metadata().chain_err(|| ErrorKind::ComponentDirPermissionsFailed));
-            if meta.is_dir() {
-                let mut perm = meta.permissions();
-                perm.set_mode(0o755);
-                try!(fs::set_permissions(entry.path(), perm).chain_err(|| ErrorKind::ComponentFilePermissionsFailed));
-            } else {
-                let mut perm = meta.permissions();
-                perm.set_mode(0o644);
-                try!(fs::set_permissions(entry.path(), perm).chain_err(|| ErrorKind::ComponentFilePermissionsFailed));
-            }
+            let mut perm = meta.permissions();
+            perm.set_mode(if needs_x(&meta) { 0o755 } else { 0o644 });
+            try!(fs::set_permissions(entry.path(), perm).chain_err(|| ErrorKind::ComponentFilePermissionsFailed));
         }
-    } else if is_bin {
-        let mut perm = try!(fs::metadata(dest_path).chain_err(|| ErrorKind::ComponentFilePermissionsFailed))
-                           .permissions();
-        perm.set_mode(0o755);
-        try!(fs::set_permissions(dest_path, perm).chain_err(|| ErrorKind::ComponentFilePermissionsFailed));
     } else {
-        let mut perm = try!(fs::metadata(dest_path).chain_err(|| ErrorKind::ComponentFilePermissionsFailed))
-                           .permissions();
-        perm.set_mode(0o644);
+        let meta = try!(fs::metadata(dest_path).chain_err(|| ErrorKind::ComponentFilePermissionsFailed));
+        let mut perm = meta.permissions();
+        perm.set_mode(if is_bin || needs_x(&meta) { 0o755 } else { 0o644 });
         try!(fs::set_permissions(dest_path, perm).chain_err(|| ErrorKind::ComponentFilePermissionsFailed));
     }
 
diff --git a/src/rustup-dist/tests/dist.rs b/src/rustup-dist/tests/dist.rs
index 2e42432703..7f5ac9295e 100644
--- a/src/rustup-dist/tests/dist.rs
+++ b/src/rustup-dist/tests/dist.rs
@@ -118,7 +118,7 @@ pub fn create_mock_channel(channel: &str, date: &str,
                              MockCommand::File("bin/rustc".to_string()),
                              ],
                          vec![
-                             ("bin/rustc".to_string(), contents.clone())
+                             ("bin/rustc".to_string(), contents.clone(), false)
                                  ],
                          ),
                         ]
@@ -152,7 +152,7 @@ pub fn create_mock_channel(channel: &str, date: &str,
                              MockCommand::File("lib/libstd.rlib".to_string()),
                              ],
                          vec![
-                             ("lib/libstd.rlib".to_string(), contents.clone())
+                             ("lib/libstd.rlib".to_string(), contents.clone(), false)
                                  ],
                          ),
                         ]
@@ -170,7 +170,7 @@ pub fn create_mock_channel(channel: &str, date: &str,
                              MockCommand::File("lib/i686-apple-darwin/libstd.rlib".to_string()),
                              ],
                          vec![
-                             ("lib/i686-apple-darwin/libstd.rlib".to_string(), contents.clone())
+                             ("lib/i686-apple-darwin/libstd.rlib".to_string(), contents.clone(), false)
                                  ],
                          ),
                         ]
@@ -188,7 +188,7 @@ pub fn create_mock_channel(channel: &str, date: &str,
                              MockCommand::File("lib/i686-unknown-linux-gnu/libstd.rlib".to_string()),
                              ],
                          vec![
-                             ("lib/i686-unknown-linux-gnu/libstd.rlib".to_string(), contents.clone())
+                             ("lib/i686-unknown-linux-gnu/libstd.rlib".to_string(), contents.clone(), false)
                                  ],
                          ),
                         ]
@@ -215,7 +215,7 @@ pub fn create_mock_channel(channel: &str, date: &str,
                              MockCommand::File("bin/bonus".to_string()),
                              ],
                          vec![
-                             ("bin/bonus".to_string(), contents.clone())
+                             ("bin/bonus".to_string(), contents.clone(), false)
                                  ],
                          ),
                         ]
diff --git a/src/rustup-dist/tests/install.rs b/src/rustup-dist/tests/install.rs
index b7758de456..b1bb28ab03 100644
--- a/src/rustup-dist/tests/install.rs
+++ b/src/rustup-dist/tests/install.rs
@@ -27,13 +27,13 @@ fn mock_smoke_test() {
                           vec![MockCommand::File("bin/foo".to_string()),
                                MockCommand::File("lib/bar".to_string()),
                                MockCommand::Dir("doc/stuff".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into()),
-                               ("lib/bar".to_string(), "bar".into()),
-                               ("doc/stuff/doc1".to_string(), "".into()),
-                               ("doc/stuff/doc2".to_string(), "".into())]),
+                          vec![("bin/foo".to_string(), "foo".into(), false),
+                               ("lib/bar".to_string(), "bar".into(), false),
+                               ("doc/stuff/doc1".to_string(), "".into(), false),
+                               ("doc/stuff/doc2".to_string(), "".into(), false)]),
                          ("mycomponent2".to_string(),
                           vec![MockCommand::File("bin/quux".to_string())],
-                          vec![("bin/quux".to_string(), "quux".into())]
+                          vec![("bin/quux".to_string(), "quux".into(), false)]
                           )]
     };
 
@@ -56,11 +56,11 @@ fn package_contains() {
     let mock = MockInstallerBuilder {
         components: vec![("mycomponent".to_string(),
                           vec![MockCommand::File("bin/foo".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into())],
+                          vec![("bin/foo".to_string(), "foo".into(), false)],
                           ),
                          ("mycomponent2".to_string(),
                           vec![MockCommand::File("bin/bar".to_string())],
-                          vec![("bin/bar".to_string(), "bar".into())]
+                          vec![("bin/bar".to_string(), "bar".into(), false)]
                           )]
     };
 
@@ -78,7 +78,7 @@ fn package_bad_version() {
     let mock = MockInstallerBuilder {
         components: vec![("mycomponent".to_string(),
                           vec![MockCommand::File("bin/foo".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into())])]
+                          vec![("bin/foo".to_string(), "foo".into(), false)])]
     };
 
     mock.build(tempdir.path());
@@ -98,10 +98,10 @@ fn basic_install() {
                           vec![MockCommand::File("bin/foo".to_string()),
                                MockCommand::File("lib/bar".to_string()),
                                MockCommand::Dir("doc/stuff".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into()),
-                               ("lib/bar".to_string(), "bar".into()),
-                               ("doc/stuff/doc1".to_string(), "".into()),
-                               ("doc/stuff/doc2".to_string(), "".into())])]
+                          vec![("bin/foo".to_string(), "foo".into(), false),
+                               ("lib/bar".to_string(), "bar".into(), false),
+                               ("doc/stuff/doc1".to_string(), "".into(), false),
+                               ("doc/stuff/doc2".to_string(), "".into(), false)])]
     };
 
     mock.build(pkgdir.path());
@@ -136,10 +136,10 @@ fn multiple_component_install() {
     let mock = MockInstallerBuilder {
         components: vec![("mycomponent".to_string(),
                           vec![MockCommand::File("bin/foo".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into())]),
+                          vec![("bin/foo".to_string(), "foo".into(), false)]),
                          ("mycomponent2".to_string(),
                           vec![MockCommand::File("lib/bar".to_string())],
-                          vec![("lib/bar".to_string(), "bar".into())])]
+                          vec![("lib/bar".to_string(), "bar".into(), false)])]
     };
 
     mock.build(pkgdir.path());
@@ -176,13 +176,13 @@ fn uninstall() {
                           vec![MockCommand::File("bin/foo".to_string()),
                                MockCommand::File("lib/bar".to_string()),
                                MockCommand::Dir("doc/stuff".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into()),
-                               ("lib/bar".to_string(), "bar".into()),
-                               ("doc/stuff/doc1".to_string(), "".into()),
-                               ("doc/stuff/doc2".to_string(), "".into())]),
+                          vec![("bin/foo".to_string(), "foo".into(), false),
+                               ("lib/bar".to_string(), "bar".into(), false),
+                               ("doc/stuff/doc1".to_string(), "".into(), false),
+                               ("doc/stuff/doc2".to_string(), "".into(), false)]),
                          ("mycomponent2".to_string(),
                           vec![MockCommand::File("lib/quux".to_string())],
-                          vec![("lib/quux".to_string(), "quux".into())])]
+                          vec![("lib/quux".to_string(), "quux".into(), false)])]
     };
 
     mock.build(pkgdir.path());
@@ -234,7 +234,7 @@ fn component_bad_version() {
     let mock = MockInstallerBuilder {
         components: vec![("mycomponent".to_string(),
                           vec![MockCommand::File("bin/foo".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into())])]
+                          vec![("bin/foo".to_string(), "foo".into(), false)])]
     };
 
     mock.build(pkgdir.path());
@@ -276,11 +276,14 @@ fn unix_permissions() {
         components: vec![("mycomponent".to_string(),
                           vec![MockCommand::File("bin/foo".to_string()),
                                MockCommand::File("lib/bar".to_string()),
+                               MockCommand::File("lib/foobar".to_string()),
                                MockCommand::Dir("doc/stuff".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into()),
-                               ("lib/bar".to_string(), "bar".into()),
-                               ("doc/stuff/doc1".to_string(), "".into()),
-                               ("doc/stuff/morestuff/doc2".to_string(), "".into())])]
+                          vec![("bin/foo".to_string(), "foo".into(), false),
+                               ("lib/bar".to_string(), "bar".into(), false),
+                               ("lib/foobar".to_string(), "foobar".into(), true),
+                               ("doc/stuff/doc1".to_string(), "".into(), false),
+                               ("doc/stuff/morestuff/doc2".to_string(), "".into(), false),
+                               ("doc/stuff/morestuff/tool".to_string(), "".into(), true)])]
     };
 
     mock.build(pkgdir.path());
@@ -304,6 +307,8 @@ fn unix_permissions() {
     assert_eq!(m, 0o755);
     let m = fs::metadata(instdir.path().join("lib/bar")).unwrap().permissions().mode();
     assert_eq!(m, 0o644);
+    let m = fs::metadata(instdir.path().join("lib/foobar")).unwrap().permissions().mode();
+    assert_eq!(m, 0o755);
     let m = fs::metadata(instdir.path().join("doc/stuff/")).unwrap().permissions().mode();
     assert_eq!(m, 0o755);
     let m = fs::metadata(instdir.path().join("doc/stuff/doc1")).unwrap().permissions().mode();
@@ -312,6 +317,8 @@ fn unix_permissions() {
     assert_eq!(m, 0o755);
     let m = fs::metadata(instdir.path().join("doc/stuff/morestuff/doc2")).unwrap().permissions().mode();
     assert_eq!(m, 0o644);
+    let m = fs::metadata(instdir.path().join("doc/stuff/morestuff/tool")).unwrap().permissions().mode();
+    assert_eq!(m, 0o755);
 }
 
 // Installing to a prefix that doesn't exist creates it automatically
@@ -322,7 +329,7 @@ fn install_to_prefix_that_does_not_exist() {
     let mock = MockInstallerBuilder {
         components: vec![("mycomponent".to_string(),
                           vec![MockCommand::File("bin/foo".to_string())],
-                          vec![("bin/foo".to_string(), "foo".into())])]
+                          vec![("bin/foo".to_string(), "foo".into(), false)])]
     };
 
     mock.build(pkgdir.path());
diff --git a/src/rustup-mock/src/clitools.rs b/src/rustup-mock/src/clitools.rs
index 07854d22ff..1046eab3d4 100644
--- a/src/rustup-mock/src/clitools.rs
+++ b/src/rustup-mock/src/clitools.rs
@@ -513,7 +513,7 @@ fn build_mock_std_installer(trip: &str) -> MockInstallerBuilder {
         components: vec![
             (format!("rust-std-{}", trip.clone()),
              vec![MockCommand::File(format!("lib/rustlib/{}/libstd.rlib", trip))],
-             vec![(format!("lib/rustlib/{}/libstd.rlib", trip), "".into())])
+             vec![(format!("lib/rustlib/{}/libstd.rlib", trip), "".into(), false)])
             ]
     }
 }
@@ -524,8 +524,8 @@ fn build_mock_cross_std_installer(target: &str, date: &str) -> MockInstallerBuil
             (format!("rust-std-{}", target.clone()),
              vec![MockCommand::File(format!("lib/rustlib/{}/lib/libstd.rlib", target)),
                   MockCommand::File(format!("lib/rustlib/{}/lib/{}", target, date))],
-             vec![(format!("lib/rustlib/{}/lib/libstd.rlib", target), "".into()),
-                  (format!("lib/rustlib/{}/lib/{}", target, date), "".into())])
+             vec![(format!("lib/rustlib/{}/lib/libstd.rlib", target), "".into(), false),
+                  (format!("lib/rustlib/{}/lib/{}", target, date), "".into(), false)])
             ]
     }
 }
@@ -546,7 +546,7 @@ fn build_mock_rustc_installer(target: &str, version: &str, version_hash_: &str)
         components: vec![
             ("rustc".to_string(),
              vec![MockCommand::File(rustc.clone())],
-             vec![(rustc, mock_bin("rustc", version, &version_hash))])
+             vec![(rustc, mock_bin("rustc", version, &version_hash), false)])
                 ]
     }
 }
@@ -557,7 +557,7 @@ fn build_mock_cargo_installer(version: &str, version_hash: &str) -> MockInstalle
         components: vec![
             ("cargo".to_string(),
              vec![MockCommand::File(cargo.clone())],
-             vec![(cargo, mock_bin("cargo", version, version_hash))])
+             vec![(cargo, mock_bin("cargo", version, version_hash), false)])
                 ]
     }
 }
@@ -568,7 +568,7 @@ fn build_mock_rls_installer(version: &str, version_hash: &str) -> MockInstallerB
         components: vec![
             ("rls".to_string(),
              vec![MockCommand::File(cargo.clone())],
-             vec![(cargo, mock_bin("rls", version, version_hash))])
+             vec![(cargo, mock_bin("rls", version, version_hash), false)])
                 ]
     }
 }
@@ -578,7 +578,7 @@ fn build_mock_rust_doc_installer() -> MockInstallerBuilder {
         components: vec![
             ("rust-docs".to_string(),
              vec![MockCommand::File("share/doc/rust/html/index.html".to_string())],
-             vec![("share/doc/rust/html/index.html".to_string(), "".into())])
+             vec![("share/doc/rust/html/index.html".to_string(), "".into(), false)])
                 ]
     }
 }
@@ -588,7 +588,7 @@ fn build_mock_rust_analysis_installer(trip: &str) -> MockInstallerBuilder {
         components: vec![
             (format!("rust-analysis-{}", trip),
              vec![MockCommand::File(format!("lib/rustlib/{}/analysis/libfoo.json", trip))],
-             vec![(format!("lib/rustlib/{}/analysis/libfoo.json", trip), "".into())])
+             vec![(format!("lib/rustlib/{}/analysis/libfoo.json", trip), "".into(), false)])
                 ]
     }
 }
@@ -598,7 +598,7 @@ fn build_mock_rust_src_installer() -> MockInstallerBuilder {
         components: vec![
             ("rust-src".to_string(),
              vec![MockCommand::File("lib/rustlib/src/rust-src/foo.rs".to_string())],
-             vec![("lib/rustlib/src/rust-src/foo.rs".to_string(), "".into())])
+             vec![("lib/rustlib/src/rust-src/foo.rs".to_string(), "".into(), false)])
                 ]
     }
 }
diff --git a/src/rustup-mock/src/lib.rs b/src/rustup-mock/src/lib.rs
index 3a860a001b..0dd15780b0 100644
--- a/src/rustup-mock/src/lib.rs
+++ b/src/rustup-mock/src/lib.rs
@@ -33,8 +33,8 @@ pub struct MockInstallerBuilder {
 }
 
 // A component name, the installation commands for installing files
-// (either "file:" or "dir:") and the file paths and contents.
-pub type MockComponent = (String, Vec<MockCommand>, Vec<(String, Vec<u8>)>);
+// (either "file:" or "dir:") and the file paths, contents and X bit.
+pub type MockComponent = (String, Vec<MockCommand>, Vec<(String, Vec<u8>, bool)>);
 
 #[derive(Clone)]
 pub enum MockCommand {
@@ -67,13 +67,23 @@ impl MockInstallerBuilder {
             }
 
             // Create the component files
-            for &(ref f_path, ref content) in files {
-                let dir_path = component_dir.join(f_path);
-                let dir_path = dir_path.parent().unwrap();
+            for &(ref f_path, ref content, executable) in files {
+                let fname = component_dir.join(f_path);
+                let dir_path = fname.parent().unwrap().to_owned();
                 fs::create_dir_all(dir_path).unwrap();
-                let ref mut f = File::create(component_dir.join(f_path)).unwrap();
+                let ref mut f = File::create(&fname).unwrap();
 
                 f.write_all(&content).unwrap();
+                drop(f);
+                #[cfg(unix)]
+                {
+                    use std::os::unix::fs::PermissionsExt;
+                    if executable {
+                        let mut perm = fs::metadata(&fname).unwrap().permissions();
+                        perm.set_mode(0o755);
+                        fs::set_permissions(&fname, perm).unwrap();
+                    }
+                }
             }
         }