1 files changed, 36 insertions, 11 deletions

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 1d7fde994521..873ad9b3418c 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2736,7 +2736,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
 	struct ext4_sb_info *sbi;
 	struct super_block *sb;
 	ext4_fsblk_t block;
-	int err;
+	int err, len;
 
 	BUG_ON(ac->ac_status != AC_STATUS_FOUND);
 	BUG_ON(ac->ac_b_ex.fe_len <= 0);
@@ -2770,14 +2770,27 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
 		+ ac->ac_b_ex.fe_start
 		+ le32_to_cpu(es->s_first_data_block);
 
-	if (block == ext4_block_bitmap(sb, gdp) ||
-			block == ext4_inode_bitmap(sb, gdp) ||
-			in_range(block, ext4_inode_table(sb, gdp),
-				EXT4_SB(sb)->s_itb_per_group)) {
-
+	len = ac->ac_b_ex.fe_len;
+	if (in_range(ext4_block_bitmap(sb, gdp), block, len) ||
+	    in_range(ext4_inode_bitmap(sb, gdp), block, len) ||
+	    in_range(block, ext4_inode_table(sb, gdp),
+		     EXT4_SB(sb)->s_itb_per_group) ||
+	    in_range(block + len - 1, ext4_inode_table(sb, gdp),
+		     EXT4_SB(sb)->s_itb_per_group)) {
 		ext4_error(sb, __func__,
 			   "Allocating block in system zone - block = %llu",
 			   block);
+		/* File system mounted not to panic on error
+		 * Fix the bitmap and repeat the block allocation
+		 * We leak some of the blocks here.
+		 */
+		mb_set_bits(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group),
+				bitmap_bh->b_data, ac->ac_b_ex.fe_start,
+				ac->ac_b_ex.fe_len);
+		err = ext4_journal_dirty_metadata(handle, bitmap_bh);
+		if (!err)
+			err = -EAGAIN;
+		goto out_err;
 	}
 #ifdef AGGRESSIVE_CHECK
 	{
@@ -4032,7 +4045,6 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 
 		ac->ac_op = EXT4_MB_HISTORY_ALLOC;
 		ext4_mb_normalize_request(ac, ar);
-
 repeat:
 		/* allocate space in core */
 		ext4_mb_regular_allocator(ac);
@@ -4046,10 +4058,21 @@ repeat:
 	}
 
 	if (likely(ac->ac_status == AC_STATUS_FOUND)) {
-		ext4_mb_mark_diskspace_used(ac, handle);
-		*errp = 0;
-		block = ext4_grp_offs_to_block(sb, &ac->ac_b_ex);
-		ar->len = ac->ac_b_ex.fe_len;
+		*errp = ext4_mb_mark_diskspace_used(ac, handle);
+		if (*errp ==  -EAGAIN) {
+			ac->ac_b_ex.fe_group = 0;
+			ac->ac_b_ex.fe_start = 0;
+			ac->ac_b_ex.fe_len = 0;
+			ac->ac_status = AC_STATUS_CONTINUE;
+			goto repeat;
+		} else if (*errp) {
+			ac->ac_b_ex.fe_len = 0;
+			ar->len = 0;
+			ext4_mb_show_ac(ac);
+		} else {
+			block = ext4_grp_offs_to_block(sb, &ac->ac_b_ex);
+			ar->len = ac->ac_b_ex.fe_len;
+		}
 	} else {
 		freed  = ext4_mb_discard_preallocations(sb, ac->ac_o_ex.fe_len);
 		if (freed)
@@ -4236,6 +4259,8 @@ do_more:
 		ext4_error(sb, __func__,
 			   "Freeing blocks in system zone - "
 			   "Block = %lu, count = %lu", block, count);
+		/* err = 0. ext4_std_error should be a no op */
+		goto error_return;
 	}
 
 	BUFFER_TRACE(bitmap_bh, "getting write access");