Merge pull request #409 from smcv/mount-onto-socket

Don't require mount point for a non-directory to be a regular file

2 files changed, 15 insertions, 3 deletions

diff --git a/tests/test-run.sh b/tests/test-run.sh
index 4fb5e22..da7265f 100755
--- a/tests/test-run.sh
+++ b/tests/test-run.sh
@@ -80,7 +80,7 @@ if [ -z "${BWRAP_MUST_WORK-}" ] && ! $RUN true; then
     skip Seems like bwrap is not working at all. Maybe setuid is not working
 fi
 
-echo "1..50"
+echo "1..51"
 
 # Test help
 ${BWRAP} --help > help.txt
@@ -398,4 +398,11 @@ command stat -c '%a' new-file-mountpoint > new-file-permissions
 assert_file_has_content new-file-permissions 444
 echo "ok - Files and directories created as mount points have expected permissions"
 
+if [ -S /dev/log ]; then
+    $RUN --bind / / --bind "$(realpath /dev/log)" "$(realpath /dev/log)" true
+    echo "ok - Can bind-mount a socket (/dev/log) onto a socket"
+else
+    echo "ok # SKIP - /dev/log is not a socket, cannot test bubblewrap#409"
+fi
+
 echo "ok - End of test"
diff --git a/utils.c b/utils.c
index a99a865..ea15158 100644
--- a/utils.c
+++ b/utils.c
@@ -448,9 +448,14 @@ ensure_file (const char *path,
 
   /* We check this ahead of time, otherwise
      the create file will fail in the read-only
-     case with EROFS instead of EEXIST */
+     case with EROFS instead of EEXIST.
+
+     We're trying to set up a mount point for a non-directory, so any
+     non-directory, non-symlink is acceptable - it doesn't necessarily
+     have to be a regular file. */
   if (stat (path, &buf) ==  0 &&
-      S_ISREG (buf.st_mode))
+      !S_ISDIR (buf.st_mode) &&
+      !S_ISLNK (buf.st_mode))
     return 0;
 
   if (create_file (path, mode, NULL) != 0 &&  errno != EEXIST)