commit e5cafce3ad0f8652d6849314d951459c2bff7233 upstream.
A NULL pointer dereference may occur in __ceph_remove_cap with some of the
callbacks used in ceph_iterate_session_caps, namely trim_caps_cb and
remove_session_caps_cb. Those callers hold the session->s_mutex, so they
are prevented from concurrent execution, but ceph_evict_inode does not.
Since the callers of this function hold the i_ceph_lock, the fix is simply
a matter of returning immediately if caps->ci is NULL.
Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/43272
Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit dc3da0461cc4b76f2d0c5b12247fcb3b520edbbf ]
Nothing ensures that session will still be valid by the time we
dereference the pointer. Take and put a reference.
In principle, we should always be able to get a reference here, but
throw a warning if that's ever not the case.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fb33c114d3ed5bdac230716f5b0a93b56b92a90d ]
It's possible for the VFS to completely forget about an inode, but for
it to still be sitting on the cap release queue. If the MDS sends the
client a cap message for such an inode, it just ignores it today, which
can lead to a stall of up to 5s until the cap release queue is flushed.
If we get a cap message for an inode that can't be located, then go
ahead and flush the cap release queue.
Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/45532
Fixes: 1e9c2eb6811e ("ceph: delete stale dentry when last reference is dropped")
Reported-and-Tested-by: Andrej Filipčič <andrej.filipcic@ijs.si>
Suggested-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4d8e28ff3106b093d98bfd2eceb9b430c70a8758 ]
If the ceph_mdsc_open_export_target_session() return fails, it will
do a "goto retry", but the session mutex has already been unlocked.
Re-lock the mutex in that case to ensure that we don't unlock it
twice.
Signed-off-by: Wu Bo <wubo40@huawei.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0aa971b6fd3f92afef6afe24ef78d9bb14471519 ]
1. try_get_cap_refs() fails to get caps and finds that mds_wanted
does not include what it wants. It returns -ESTALE.
2. ceph_get_caps() calls ceph_renew_caps(). ceph_renew_caps() finds
that inode has cap, so it calls ceph_check_caps().
3. ceph_check_caps() finds that issued caps (without checking if it's
stale) already includes caps wanted by open file, so it skips
updating wanted caps.
Above events can cause an infinite loop inside ceph_get_caps().
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Luis Henriques