From 5150bf19635c335109542c19f6b84c7813810873 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Fri, 17 Apr 2020 16:36:15 +0100 Subject: [PATCH] btrfs: fix memory leak of transaction when deleting unused block group When cleaning pinned extents right before deleting an unused block group, we check if there's still a previous transaction running and if so we increment its reference count before using it for cleaning pinned ranges in its pinned extents iotree. However we ended up never decrementing the reference count after using the transaction, resulting in a memory leak. Fix it by decrementing the reference count. Fixes: fe119a6eeb6705 ("btrfs: switch to per-transaction pinned extents") Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/block-group.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 47f66c6a7d7f..af9e9a008724 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1288,11 +1288,15 @@ static bool clean_pinned_extents(struct btrfs_trans_handle *trans, if (ret) goto err; mutex_unlock(&fs_info->unused_bg_unpin_mutex); + if (prev_trans) + btrfs_put_transaction(prev_trans); return true; err: mutex_unlock(&fs_info->unused_bg_unpin_mutex); + if (prev_trans) + btrfs_put_transaction(prev_trans); btrfs_dec_block_group_ro(bg); return false; }