3 files changed, 31 insertions, 3 deletions

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index a40b1f96c021..d9b66c4a26e8 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -356,6 +356,7 @@ void ext4_validate_block_bitmap(struct super_block *sb,
                                struct buffer_head *bh)
 {
         ext4_fsblk_t    blk;
+        struct ext4_group_info *grp = ext4_get_group_info(sb, block_group);
 
         if (buffer_verified(bh))
                 return;
@@ -366,12 +367,14 @@ void ext4_validate_block_bitmap(struct super_block *sb,
                 ext4_unlock_group(sb, block_group);
                 ext4_error(sb, "bg %u: block %llu: invalid block bitmap",
                            block_group, blk);
+                set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
                 return;
         }
         if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group,
                         desc, bh))) {
                 ext4_unlock_group(sb, block_group);
                 ext4_error(sb, "bg %u: bad block bitmap checksum", block_group);
+                set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
                 return;
         }
         set_buffer_verified(bh);
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 2e5818267565..02b764b4e635 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2480,9 +2480,12 @@ struct ext4_group_info {
 
 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
+#define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT     2
 
 #define EXT4_MB_GRP_NEED_INIT(grp)      \
         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
+#define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)        \
+        (test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
 
 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index aa7d058e9e48..a41e3ba8cfaa 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -751,13 +751,15 @@ void ext4_mb_generate_buddy(struct super_block *sb,
 
         if (free != grp->bb_free) {
                 ext4_grp_locked_error(sb, group, 0, 0,
-                                      "%u clusters in bitmap, %u in gd",
+                                      "%u clusters in bitmap, %u in gd; "
+                                      "block bitmap corrupt.",
                                       free, grp->bb_free);
                 /*
-                 * If we intent to continue, we consider group descritor
+                 * If we intend to continue, we consider group descriptor
                  * corrupt and update bb_free using bitmap value
                  */
                 grp->bb_free = free;
+                set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
         }
         mb_set_largest_free_order(sb, grp);
 
@@ -1398,6 +1400,10 @@ static void mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
 
         BUG_ON(last >= (sb->s_blocksize << 3));
         assert_spin_locked(ext4_group_lock_ptr(sb, e4b->bd_group));
+        /* Don't bother if the block group is corrupt. */
+        if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(e4b->bd_info)))
+                return;
+
         mb_check_buddy(e4b);
         mb_free_blocks_double(inode, e4b, first, count);
 
@@ -1423,7 +1429,11 @@ static void mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
                                       inode ? inode->i_ino : 0,
                                       blocknr,
                                       "freeing already freed block "
-                                      "(bit %u)", block);
+                                      "(bit %u); block bitmap corrupt.",
+                                      block);
+                /* Mark the block group as corrupt. */
+                set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
+                        &e4b->bd_info->bb_state);
                 mb_regenerate_buddy(e4b);
                 goto done;
         }
@@ -1790,6 +1800,11 @@ int ext4_mb_find_by_goal(struct ext4_allocation_context *ac,
         if (err)
                 return err;
 
+        if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(e4b->bd_info))) {
+                ext4_mb_unload_buddy(e4b);
+                return 0;
+        }
+
         ext4_lock_group(ac->ac_sb, group);
         max = mb_find_extent(e4b, ac->ac_g_ex.fe_start,
                              ac->ac_g_ex.fe_len, &ex);
@@ -1987,6 +2002,9 @@ static int ext4_mb_good_group(struct ext4_allocation_context *ac,
         if (cr <= 2 && free < ac->ac_g_ex.fe_len)
                 return 0;
 
+        if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(grp)))
+                return 0;
+
         /* We only do this if the grp has never been initialized */
         if (unlikely(EXT4_MB_GRP_NEED_INIT(grp))) {
                 int ret = ext4_mb_init_group(ac->ac_sb, group);
@@ -4674,6 +4692,10 @@ do_more:
         overflow = 0;
         ext4_get_group_no_and_offset(sb, block, &block_group, &bit);
 
+        if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(
+                        ext4_get_group_info(sb, block_group))))
+                return;
+
         /*
          * Check to see if we are freeing blocks across a group
          * boundary.