diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index 742cdfa..8b9bce1 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -700,6 +700,29 @@
 }
 
 //
+// Mechanism to allow fsck to be triggered by setting ro.preventative_fsck
+// Introduced to address b/305658663
+// If the property value is not equal to the flag file contents, trigger
+// fsck and store the property value in the flag file
+// If we want to trigger again, simply change the property value
+//
+static bool check_if_preventative_fsck_needed(const FstabEntry& entry) {
+    const char* flag_file = "/metadata/vold/preventative_fsck";
+    if (entry.mount_point != "/data") return false;
+
+    // Don't error check - both default to empty string, which is OK
+    std::string prop = android::base::GetProperty("ro.preventative_fsck", "");
+    std::string flag;
+    android::base::ReadFileToString(flag_file, &flag);
+    if (prop == flag) return false;
+    // fsck is run immediately, so assume it runs or there is some deeper problem
+    if (!android::base::WriteStringToFile(prop, flag_file))
+        PERROR << "Failed to write file " << flag_file;
+    LINFO << "Run preventative fsck on /data";
+    return true;
+}
+
+//
 // Prepare the filesystem on the given block device to be mounted.
 //
 // If the "check" option was given in the fstab record, or it seems that the
@@ -749,7 +772,7 @@
         }
     }
 
-    if (entry.fs_mgr_flags.check ||
+    if (check_if_preventative_fsck_needed(entry) || entry.fs_mgr_flags.check ||
         (fs_stat & (FS_STAT_UNCLEAN_SHUTDOWN | FS_STAT_QUOTA_ENABLED))) {
         check_fs(blk_device, entry.fs_type, mount_point, &fs_stat);
     }
diff --git a/fs_mgr/tests/vts_fs_test.cpp b/fs_mgr/tests/vts_fs_test.cpp
index 4d771fa..bf003ee 100644
--- a/fs_mgr/tests/vts_fs_test.cpp
+++ b/fs_mgr/tests/vts_fs_test.cpp
@@ -30,6 +30,24 @@
     return android::base::GetIntProperty("ro.vendor.api_level", -1);
 }
 
+// Returns true iff the device has the specified feature.
+bool DeviceSupportsFeature(const char* feature) {
+    bool device_supports_feature = false;
+    FILE* p = popen("pm list features", "re");
+    if (p) {
+        char* line = NULL;
+        size_t len = 0;
+        while (getline(&line, &len, p) > 0) {
+            if (strstr(line, feature)) {
+                device_supports_feature = true;
+                break;
+            }
+        }
+        pclose(p);
+    }
+    return device_supports_feature;
+}
+
 TEST(fs, ErofsSupported) {
     // T-launch GKI kernels and higher must support EROFS.
     if (GetVsrLevel() < __ANDROID_API_T__) {
@@ -80,7 +98,8 @@
     ASSERT_TRUE(android::base::Readlink("/dev/block/by-name/userdata", &userdata_bdev));
 
     std::vector<std::string> must_be_f2fs = {"/data"};
-    if (vsr_level >= __ANDROID_API_U__) {
+    if (vsr_level >= __ANDROID_API_U__ &&
+        !DeviceSupportsFeature("android.hardware.type.automotive")) {
         must_be_f2fs.emplace_back("/metadata");
     }
 
diff --git a/libcutils/ashmem-dev.cpp b/libcutils/ashmem-dev.cpp
index 6a27f9a..56d6875 100644
--- a/libcutils/ashmem-dev.cpp
+++ b/libcutils/ashmem-dev.cpp
@@ -349,6 +349,12 @@
         return -1;
     }
 
+    // forbid size changes to match ashmem behaviour
+    if (fcntl(fd, F_ADD_SEALS, F_SEAL_GROW | F_SEAL_SHRINK) == -1) {
+        ALOGE("memfd_create(%s, %zd) F_ADD_SEALS failed: %m", name, size);
+        return -1;
+    }
+
     if (debug_log) {
         ALOGE("memfd_create(%s, %zd) success. fd=%d\n", name, size, fd.get());
     }
@@ -400,14 +406,29 @@
 }
 
 static int memfd_set_prot_region(int fd, int prot) {
-    /* Only proceed if an fd needs to be write-protected */
+    int seals = fcntl(fd, F_GET_SEALS);
+    if (seals == -1) {
+        ALOGE("memfd_set_prot_region(%d, %d): F_GET_SEALS failed: %s\n", fd, prot, strerror(errno));
+        return -1;
+    }
+
     if (prot & PROT_WRITE) {
+        /* Now we want the buffer to be read-write, let's check if the buffer
+         * has been previously marked as read-only before, if so return error
+         */
+        if (seals & F_SEAL_FUTURE_WRITE) {
+            ALOGE("memfd_set_prot_region(%d, %d): region is write protected\n", fd, prot);
+            errno = EINVAL;  // inline with ashmem error code, if already in
+                             // read-only mode
+            return -1;
+        }
         return 0;
     }
 
-    if (fcntl(fd, F_ADD_SEALS, F_SEAL_FUTURE_WRITE) == -1) {
-        ALOGE("memfd_set_prot_region(%d, %d): F_SEAL_FUTURE_WRITE seal failed: %s\n", fd, prot,
-              strerror(errno));
+    /* We would only allow read-only for any future file operations */
+    if (fcntl(fd, F_ADD_SEALS, F_SEAL_FUTURE_WRITE | F_SEAL_SEAL) == -1) {
+        ALOGE("memfd_set_prot_region(%d, %d): F_SEAL_FUTURE_WRITE | F_SEAL_SEAL seal failed: %s\n",
+              fd, prot, strerror(errno));
         return -1;
     }