1 files changed, 38 insertions, 9 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index d7b7480682b9..dadd3f995db5 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -372,20 +372,21 @@ static int ext4_block_to_path(struct inode *inode,
 }
 
 static int __ext4_check_blockref(const char *function, struct inode *inode,
-                                 __le32 *p, unsigned int max) {
-
-        unsigned int maxblocks = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es);
+                                 __le32 *p, unsigned int max)
+{
         __le32 *bref = p;
+        unsigned int blk;
+
         while (bref < p+max) {
-                if (unlikely(le32_to_cpu(*bref) >= maxblocks)) {
+                blk = le32_to_cpu(*bref++);
+                if (blk && 
+                    unlikely(!ext4_data_block_valid(EXT4_SB(inode->i_sb), 
+                                                    blk, 1))) {
                         ext4_error(inode->i_sb, function,
-                                   "block reference %u >= max (%u) "
-                                   "in inode #%lu, offset=%d",
-                                   le32_to_cpu(*bref), maxblocks,
-                                   inode->i_ino, (int)(bref-p));
+                                   "invalid block reference %u "
+                                   "in inode #%lu", blk, inode->i_ino);
                         return -EIO;
                 }
-                bref++;
         }
         return 0;
 }
@@ -1125,6 +1126,21 @@ static void ext4_da_update_reserve_space(struct inode *inode, int used)
                 ext4_discard_preallocations(inode);
 }
 
+static int check_block_validity(struct inode *inode, sector_t logical,
+                                sector_t phys, int len)
+{
+        if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), phys, len)) {
+                ext4_error(inode->i_sb, "check_block_validity",
+                           "inode #%lu logical block %llu mapped to %llu "
+                           "(size %d)", inode->i_ino,
+                           (unsigned long long) logical,
+                           (unsigned long long) phys, len);
+                WARN_ON(1);
+                return -EIO;
+        }
+        return 0;
+}
+
 /*
  * The ext4_get_blocks() function tries to look up the requested blocks,
  * and returns if the blocks are already mapped.
@@ -1170,6 +1186,13 @@ int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block,
         }
         up_read((&EXT4_I(inode)->i_data_sem));
 
+        if (retval > 0 && buffer_mapped(bh)) {
+                int ret = check_block_validity(inode, block, 
+                                               bh->b_blocknr, retval);
+                if (ret != 0)
+                        return ret;
+        }
+
         /* If it is only a block(s) look up */
         if ((flags & EXT4_GET_BLOCKS_CREATE) == 0)
                 return retval;
@@ -1245,6 +1268,12 @@ int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block,
                 ext4_da_update_reserve_space(inode, retval);
 
         up_write((&EXT4_I(inode)->i_data_sem));
+        if (retval > 0 && buffer_mapped(bh)) {
+                int ret = check_block_validity(inode, block, 
+                                               bh->b_blocknr, retval);
+                if (ret != 0)
+                        return ret;
+        }
         return retval;
 }