fix(raw): refuse to overwrite the partition table beside a mount

.github/workflows/linux.yml

@@ -50,6 +50,19 @@ jobs:
         timeout-minutes: 10
         run: cargo test --locked --release --all --all-features --no-fail-fast -- --nocapture
 
+      # The tests attaching loop devices need root, so the run above leaves
+      # them out. Only the test binary runs as root, which keeps the cached
+      # build owned by the runner. The MTD ones stay out, as they load the
+      # mtdram and nandsim kernel modules.
+      - name: Tests needing root
+        timeout-minutes: 10
+        working-directory: updatehub
+        run: |
+          bin=$(cargo test --locked --release --all-features --lib --no-run --message-format=json \
+            | sed -n 's/.*"executable":"\([^"]*\)".*/\1/p')
+          sudo env "PATH=$PATH" "$bin" --ignored --test-threads=1 \
+            --skip utils::mtd --skip installer::flash --skip installer::ubifs
+
       - name: Run listener test
         run: |
           export UH_LISTENER_TEST=updatehub-statechange.sock

flake.nix

@@ -54,6 +54,7 @@
             socat
 
             # used by excluded tests
+            e2fsprogs
             mtdutils
           ];
 

updatehub/src/object/installer/copy.rs

@@ -125,14 +125,10 @@ impl Installer for objects::Copy {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::{object::installer::tests::SERIALIZE, utils::definitions::IdExt};
+    use crate::utils::{definitions::IdExt, fs::tests::FakeLoopDevice};
     use flate2::{Compression, write::GzEncoder};
     use pretty_assertions::assert_eq;
-    use std::{
-        io::{Seek, SeekFrom, Write},
-        os::unix::fs::MetadataExt,
-        path::PathBuf,
-    };
+    use std::{io::Write, os::unix::fs::MetadataExt, path::PathBuf};
     use tokio::io::AsyncBufReadExt;
 
     const DEFAULT_BYTE: u8 = 0xF;
@@ -147,21 +143,9 @@ mod tests {
     where
         F: FnMut(&mut objects::Copy),
     {
-        // Generate a sparse file for the faked device use
-        let mut image = tempfile::NamedTempFile::new()?;
-        image.seek(SeekFrom::Start(1024 * 1024 + FILE_SIZE as u64))?;
-        image.write_all(&[0])?;
-
         // Setup faked device
-        let (loopdev, device) = {
-            // Loop device next_free is not thread safe
-            let mutex = SERIALIZE.clone();
-            let _mutex = mutex.lock().unwrap();
-            let loopdev = loopdev::LoopControl::open()?.next_free()?;
-            let device = loopdev.path().unwrap();
-            loopdev.attach_file(image.path())?;
-            (loopdev, device)
-        };
+        let loop_device = FakeLoopDevice::new(1024 * 1024 + FILE_SIZE as u64 + 1)?;
+        let device = loop_device.device.clone();
 
         // Format the faked device
         utils::fs::format(&device, definitions::Filesystem::Ext4, None)?;
@@ -258,8 +242,6 @@ mod tests {
             }
         }
 
-        loopdev.detach()?;
-
         Ok(())
     }