Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 bugfixes from Ted Ts'o:
 "Bug fixes for ext4; most of which relate to vulnerabilities where a
  maliciously crafted file system image can result in a kernel OOPS or
  hang.

  At least one fix addresses an inline data bug could be triggered by
  userspace without the need of a crafted file system (although it does
  require that the inline data feature be enabled)"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: check superblock mapped prior to committing
  ext4: add more mount time checks of the superblock
  ext4: add more inode number paranoia checks
  ext4: avoid running out of journal credits when appending to an inline file
  jbd2: don't mark block as modified if the handle is out of credits
  ext4: never move the system.data xattr out of the inode body
  ext4: clear i_data in ext4_inode_info when removing inline data
  ext4: include the illegal physical block in the bad map ext4_error msg
  ext4: verify the depth of extent tree in ext4_find_extent()
  ext4: only look at the bg_flags field if it is valid
  ext4: make sure bitmaps and the inode table don't overlap with bg descriptors
  ext4: always check block group bounds in ext4_init_block_bitmap()
  ext4: always verify the magic number in xattr blocks
  ext4: add corruption check in ext4_xattr_set_entry()
  ext4: add warn_on_error mount option

1 files changed, 12 insertions, 2 deletions

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index f525f909b559..fb83750c1a14 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -150,7 +150,16 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
         }
 
         ext4_lock_group(sb, block_group);
-        if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
+        if (ext4_has_group_desc_csum(sb) &&
+            (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT))) {
+                if (block_group == 0) {
+                        ext4_unlock_group(sb, block_group);
+                        unlock_buffer(bh);
+                        ext4_error(sb, "Inode bitmap for bg 0 marked "
+                                   "uninitialized");
+                        err = -EFSCORRUPTED;
+                        goto out;
+                }
                 memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
                 ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb),
                                      sb->s_blocksize * 8, bh->b_data);
@@ -994,7 +1003,8 @@ got:
 
                 /* recheck and clear flag under lock if we still need to */
                 ext4_lock_group(sb, group);
-                if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
+                if (ext4_has_group_desc_csum(sb) &&
+                    (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {
                         gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
                         ext4_free_group_clusters_set(sb, gdp,
                                 ext4_free_clusters_after_init(sb, group, gdp));