The ext4_orphan_del function in fs/ext4/namei.c in the Linux kernel before 3.7.3 does not properly handle orphan-list entries for non-journal filesystems, which allows physically proximate attackers to cause a denial of service (system hang) via a crafted filesystem on removable media, as demonstrated by the e2fsprogs tests/f_orphan_extents_inode/image.gz test.