diff --git a/lfs.c b/lfs.c
index 893d9ab4..b295d0b4 100644
--- a/lfs.c
+++ b/lfs.c
@@ -9116,11 +9116,11 @@ int lfsr_mkdir(lfs_t *lfs, const char *path) {
     err = lfsr_mtree_pathlookup(lfs, &lfs->mtree, path,
             &mdir, &tag,
             &did, &name, &name_size);
-    if (err && err != LFS_ERR_EXIST) {
+    if (err && err != LFS_ERR_EXIST && err != LFS_ERR_INVAL) {
         return err;
     }
     // already exists? note orphans don't really exist
-    bool exists = (err == LFS_ERR_EXIST);
+    bool exists = (err == LFS_ERR_EXIST || err == LFS_ERR_INVAL);
     if (exists && tag != LFSR_TAG_ORPHAN) {
         return LFS_ERR_EXIST;
     }
@@ -10005,7 +10005,7 @@ int lfsr_file_opencfg(lfs_t *lfs, lfsr_file_t *file,
     int err = lfsr_mtree_pathlookup(lfs, &lfs->mtree, path,
             &file->o.mdir, &tag,
             &did, &name, &name_size);
-    if (err && err != LFS_ERR_EXIST) {
+    if (err && err != LFS_ERR_EXIST && err != LFS_ERR_INVAL) {
         return err;
     }
 
diff --git a/tests/test_dirs.toml b/tests/test_dirs.toml
index 44d2d256..84409c02 100644
--- a/tests/test_dirs.toml
+++ b/tests/test_dirs.toml
@@ -283,14 +283,14 @@ code = '''
     }
 
     // try to make root, which doesn't make sense
-    lfsr_mkdir(&lfs, "/") => LFS_ERR_INVAL;
+    lfsr_mkdir(&lfs, "/") => LFS_ERR_EXIST;
 
     // make a directory
     err = lfsr_mkdir(&lfs, "ardvark");
     assert(!err || (TEST_PLS && err == LFS_ERR_EXIST));
 
     // try to make root, which doesn't make sense
-    lfsr_mkdir(&lfs, "/") => LFS_ERR_INVAL;
+    lfsr_mkdir(&lfs, "/") => LFS_ERR_EXIST;
 
     for (int remount = 0; remount < 2; remount++) {
         // remount?
diff --git a/tests/test_files.toml b/tests/test_files.toml
index ca584678..b426e5c0 100644
--- a/tests/test_files.toml
+++ b/tests/test_files.toml
@@ -456,16 +456,16 @@ code = '''
 
     // try reading our root as a file
     lfsr_file_t file;
-    lfsr_file_open(&lfs, &file, "/", LFS_O_RDONLY) => LFS_ERR_INVAL;
+    lfsr_file_open(&lfs, &file, "/", LFS_O_RDONLY) => LFS_ERR_ISDIR;
 
     // try writing our root as a file
-    lfsr_file_open(&lfs, &file, "/", LFS_O_WRONLY) => LFS_ERR_INVAL;
+    lfsr_file_open(&lfs, &file, "/", LFS_O_WRONLY) => LFS_ERR_ISDIR;
     lfsr_file_open(&lfs, &file, "/",
-            LFS_O_WRONLY | LFS_O_TRUNC) => LFS_ERR_INVAL;
+            LFS_O_WRONLY | LFS_O_TRUNC) => LFS_ERR_ISDIR;
     lfsr_file_open(&lfs, &file, "/",
-            LFS_O_WRONLY | LFS_O_CREAT) => LFS_ERR_INVAL;
+            LFS_O_WRONLY | LFS_O_CREAT) => LFS_ERR_ISDIR;
     lfsr_file_open(&lfs, &file, "/",
-            LFS_O_WRONLY | LFS_O_CREAT | LFS_O_TRUNC) => LFS_ERR_INVAL;
+            LFS_O_WRONLY | LFS_O_CREAT | LFS_O_TRUNC) => LFS_ERR_ISDIR;
 
     // try rename a file on top of our directory
     lfsr_file_open(&lfs, &file, "not_hello",
diff --git a/tests/test_paths.toml b/tests/test_paths.toml
index ab801b67..4d4046d3 100644
--- a/tests/test_paths.toml
+++ b/tests/test_paths.toml
@@ -219,10 +219,10 @@ code = '''
     assert(info.type == LFS_TYPE_DIR);
     assert(info.size == 0);
 
-    lfsr_mkdir(&lfs, "/") => LFS_ERR_INVAL;
+    lfsr_mkdir(&lfs, "/") => LFS_ERR_EXIST;
     lfsr_file_t file;
     lfsr_file_open(&lfs, &file, "/",
-            LFS_O_WRONLY | LFS_O_CREAT) => LFS_ERR_INVAL;
+            LFS_O_WRONLY | LFS_O_CREAT) => LFS_ERR_ISDIR;
 
     lfsr_remove(&lfs, "/") => LFS_ERR_INVAL;
     lfsr_unmount(&lfs) => 0;