ext4: prevent a fs with errors from being resized

A filesystem with errors is not allowed to being resized, otherwise,
it is easy to destroy the filesystem.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 10 insertions, 0 deletions

diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index 0213f631271f..53d979541b31 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -23,6 +23,16 @@ int ext4_resize_begin(struct super_block *sb)
         if (!capable(CAP_SYS_RESOURCE))
                 return -EPERM;
 
+        /*
+         * We are not allowed to do online-resizing on a filesystem mounted
+         * with error, because it can destroy the filesystem easily.
+         */
+        if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
+                ext4_warning(sb, "There are errors in the filesystem, "
+                             "so online resizing is not allowed\n");
+                return -EPERM;
+        }
+
         if (test_and_set_bit_lock(EXT4_RESIZING, &EXT4_SB(sb)->s_resize_flags))
                 ret = -EBUSY;