In several places, the kcephfs client accesses dentry->d_parent without holding appropriate locking. This is not safe, as you can race with renames that can morph the tree such that is changes and dentries found previously can end up freed. This patchset fixes these places to access the parent(s) safely, mostly using the rcu_read_lock(). Note that I'm not aware of any specific bug reports in this area -- these were just discovered by inspection (mostly by Zheng). This passes xfstests at least up to test generic/095, where we hit an unrelated softlockup in the splice write code (http://tracker.ceph.com/issues/18130). Tracker bug link: http://tracker.ceph.com/issues/18148 Jeff Layton (3): ceph: clean up unsafe d_parent access in __choose_mds ceph: clean up unsafe d_parent accesses in build_dentry_path ceph: fix unsafe dcache access in ceph_encode_dentry_release fs/ceph/caps.c | 7 ++++-- fs/ceph/mds_client.c | 68 +++++++++++++++++++++++++++++++++++----------------- 2 files changed, 51 insertions(+), 24 deletions(-) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
