Commit 6374e57a authored by Chris Mason's avatar Chris Mason Committed by David Sterba
Browse files

btrfs: fix integer overflow in calc_reclaim_items_nr 



Dave Jones hit a WARN_ON(nr < 0) in btrfs_wait_ordered_roots() with
v4.12-rc6.  This was because commit 70e7af24 made it possible for
calc_reclaim_items_nr() to return a negative number.  It's not really a
bug in that commit, it just didn't go far enough down the stack to find
all the possible 64->32 bit overflows.

This switches calc_reclaim_items_nr() to return a u64 and changes everyone
that uses the results of that math to u64 as well.

Reported-by: default avatarDave Jones <davej@codemonkey.org.uk>
Fixes: 70e7af24 ("Btrfs: fix delalloc accounting leak caused by u32 overflow")
Signed-off-by: default avatarChris Mason <clm@fb.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent ded56184

fs/btrfs/dev-replace.c

+2 −2
Original line number Diff line number Diff line
@@ -388,7 +388,7 @@ int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, 
	if (ret)

		btrfs_err(fs_info, "kobj add dev failed %d", ret);



	btrfs_wait_ordered_roots(fs_info, -1, 0, (u64)-1);

	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);



	/* force writing the updated state information to disk */

	trans = btrfs_start_transaction(root, 0);
@@ -507,7 +507,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, 
		mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);

		return ret;

	}

	btrfs_wait_ordered_roots(fs_info, -1, 0, (u64)-1);

	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);



	trans = btrfs_start_transaction(root, 0);

	if (IS_ERR(trans)) {

fs/btrfs/extent-tree.c

+6 −6
Original line number Diff line number Diff line
@@ -4288,7 +4288,7 @@ commit_trans: 


			if (need_commit > 0) {

				btrfs_start_delalloc_roots(fs_info, 0, -1);

				btrfs_wait_ordered_roots(fs_info, -1, 0,

				btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,

							 (u64)-1);

			}
@@ -4748,14 +4748,14 @@ static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info, 
	}

}



static inline int calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,

static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,

					u64 to_reclaim)

{

	u64 bytes;

	int nr;

	u64 nr;



	bytes = btrfs_calc_trans_metadata_size(fs_info, 1);

	nr = (int)div64_u64(to_reclaim, bytes);

	nr = div64_u64(to_reclaim, bytes);

	if (!nr)

		nr = 1;

	return nr;
@@ -4774,15 +4774,15 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim, 
	struct btrfs_trans_handle *trans;

	u64 delalloc_bytes;

	u64 max_reclaim;

	u64 items;

	long time_left;

	unsigned long nr_pages;

	int loops;

	int items;

	enum btrfs_reserve_flush_enum flush;



	/* Calc the number of the pages we need flush for space reservation */

	items = calc_reclaim_items_nr(fs_info, to_reclaim);

	to_reclaim = (u64)items * EXTENT_SIZE_PER_ITEM;

	to_reclaim = items * EXTENT_SIZE_PER_ITEM;



	trans = (struct btrfs_trans_handle *)current->journal_info;

	block_rsv = &fs_info->delalloc_block_rsv;

fs/btrfs/ioctl.c

+1 −1
Original line number Diff line number Diff line
@@ -689,7 +689,7 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir, 
	if (ret)

		goto dec_and_free;



	btrfs_wait_ordered_extents(root, -1, 0, (u64)-1);

	btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);



	btrfs_init_block_rsv(&pending_snapshot->block_rsv,

			     BTRFS_BLOCK_RSV_TEMP);

fs/btrfs/ordered-data.c

+8 −9
Original line number Diff line number Diff line
@@ -663,7 +663,7 @@ static void btrfs_run_ordered_extent_work(struct btrfs_work *work) 
 * wait for all the ordered extents in a root.  This is done when balancing

 * space between drives.

 */

int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr,

u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,

			       const u64 range_start, const u64 range_len)

{

	struct btrfs_fs_info *fs_info = root->fs_info;
@@ -671,7 +671,7 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr, 
	LIST_HEAD(skipped);

	LIST_HEAD(works);

	struct btrfs_ordered_extent *ordered, *next;

	int count = 0;

	u64 count = 0;

	const u64 range_end = range_start + range_len;



	mutex_lock(&root->ordered_extent_mutex);
@@ -701,7 +701,7 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr, 


		cond_resched();

		spin_lock(&root->ordered_extent_lock);

		if (nr != -1)

		if (nr != U64_MAX)

			nr--;

		count++;

	}
@@ -720,13 +720,13 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr, 
	return count;

}



int btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr,

u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,

			     const u64 range_start, const u64 range_len)

{

	struct btrfs_root *root;

	struct list_head splice;

	int done;

	int total_done = 0;

	u64 total_done = 0;

	u64 done;



	INIT_LIST_HEAD(&splice);
@@ -748,9 +748,8 @@ int btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr, 
		total_done += done;



		spin_lock(&fs_info->ordered_root_lock);

		if (nr != -1) {

		if (nr != U64_MAX) {

			nr -= done;

			WARN_ON(nr < 0);

		}

	}

	list_splice_tail(&splice, &fs_info->ordered_roots);

fs/btrfs/ordered-data.h

+2 −2
Original line number Diff line number Diff line
@@ -200,9 +200,9 @@ int btrfs_ordered_update_i_size(struct inode *inode, u64 offset, 
				struct btrfs_ordered_extent *ordered);

int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,

			   u32 *sum, int len);

int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr,

u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,

			       const u64 range_start, const u64 range_len);

int btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr,

u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,

			      const u64 range_start, const u64 range_len);

void btrfs_get_logged_extents(struct btrfs_inode *inode,

			      struct list_head *logged_list,

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