1 files changed, 13 insertions, 2 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 2cb2dd32407e..281757007ddb 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -148,6 +148,7 @@ static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
         u64 bytenr;
         u64 cow_end;
         u64 loops = 0;
+        u64 total_fs_bytes;
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct extent_buffer *leaf;
         int found_type;
@@ -157,6 +158,7 @@ static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
         int err;
         struct btrfs_key found_key;
 
+        total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
         path = btrfs_alloc_path();
         BUG_ON(!path);
 again:
@@ -189,8 +191,10 @@ again:
         found_type = btrfs_file_extent_type(leaf, item);
         extent_start = found_key.offset;
         if (found_type == BTRFS_FILE_EXTENT_REG) {
-                extent_end = extent_start +
-                       btrfs_file_extent_num_bytes(leaf, item);
+                u64 extent_num_bytes;
+
+                extent_num_bytes = btrfs_file_extent_num_bytes(leaf, item);
+                extent_end = extent_start + extent_num_bytes;
                 err = 0;
 
                 if (loops && start != extent_start)
@@ -204,6 +208,13 @@ again:
                 if (bytenr == 0)
                         goto not_found;
 
+                /*
+                 * we may be called by the resizer, make sure we're inside
+                 * the limits of the FS
+                 */
+                if (bytenr + extent_num_bytes > total_fs_bytes)
+                        goto not_found;
+
                 if (btrfs_count_snapshots_in_path(root, path, bytenr) != 1) {
                         goto not_found;
                 }