diff --git a/emubd/lfs_emubd.c b/emubd/lfs_emubd.c
index ca2b6b9..b87d6de 100644
--- a/emubd/lfs_emubd.c
+++ b/emubd/lfs_emubd.c
@@ -138,8 +138,8 @@ int lfs_emubd_prog(const struct lfs_config *cfg, lfs_block_t block,
     snprintf(emu->child, LFS_NAME_MAX, "%x", block);
 
     FILE *f = fopen(emu->path, "r+b");
-    if (!f && errno != ENOENT) {
-        return -errno;
+    if (!f) {
+        return (errno == EACCES) ? 0 : -errno;
     }
 
     // Check that file was erased
@@ -189,14 +189,14 @@ int lfs_emubd_erase(const struct lfs_config *cfg, lfs_block_t block) {
         return -errno;
     }
 
-    if (!err && S_ISREG(st.st_mode)) {
+    if (!err && S_ISREG(st.st_mode) && (S_IWUSR & st.st_mode)) {
         int err = unlink(emu->path);
         if (err) {
             return -errno;
         }
     }
 
-    if (err || S_ISREG(st.st_mode)) {
+    if (errno == ENOENT || (S_ISREG(st.st_mode) && (S_IWUSR & st.st_mode))) {
         FILE *f = fopen(emu->path, "w");
         if (!f) {
             return -errno;
diff --git a/lfs.c b/lfs.c
index b043bd9..d757ffb 100644
--- a/lfs.c
+++ b/lfs.c
@@ -531,18 +531,19 @@ static int lfs_dir_commit(lfs_t *lfs, lfs_dir_t *dir,
             }
 
             // successful commit, check checksum to make sure
-            crc = 0xffffffff;
+            uint32_t ncrc = 0xffffffff;
             err = lfs_bd_crc(lfs, dir->pair[0], 0,
-                    0x7fffffff & dir->d.size, &crc);
+                    (0x7fffffff & dir->d.size)-4, &ncrc);
             if (err) {
                 return err;
             }
 
-            if (crc == 0) {
-                break;
+            if (ncrc != crc) {
+                goto relocate;
             }
         }
 
+        break;
 relocate:
         //commit was corrupted
         LFS_DEBUG("Bad block at %d", dir->pair[0]);
diff --git a/tests/test_corrupt.sh b/tests/test_corrupt.sh
index d79a8c8..44f1cae 100755
--- a/tests/test_corrupt.sh
+++ b/tests/test_corrupt.sh
@@ -82,6 +82,17 @@ do
     lfs_chktree
 done
 
+echo "--- Block persistance ---"
+for i in {0..33}
+do 
+    rm -rf blocks
+    mkdir blocks
+    lfs_mktree
+    chmod a-w blocks/$(printf '%x' $i)
+    lfs_mktree
+    lfs_chktree
+done
+
 echo "--- Big region corruption ---"
 rm -rf blocks
 mkdir blocks