From: Robbie Ko <robbieko@xxxxxxxxxxxx> commit 5909ca110b29aa16b23b52b8de8d3bb1035fd738 upstream. When locking pages for delalloc, we check if it's dirty and mapping still matches. If it does not match, we need to return -EAGAIN and release all pages. Only the current page was put though, iterate over all the remaining pages too. CC: stable@xxxxxxxxxxxxxxx # 4.14+ Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx> Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx> Signed-off-by: Robbie Ko <robbieko@xxxxxxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/extent_io.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1923,7 +1923,8 @@ static int __process_pages_contig(struct if (!PageDirty(pages[i]) || pages[i]->mapping != mapping) { unlock_page(pages[i]); - put_page(pages[i]); + for (; i < ret; i++) + put_page(pages[i]); err = -EAGAIN; goto out; }