Jan Kara 1362f4ea20 quota: Fix race between dqput() and dquot_scan_active() ... Currently last dqput() can race with dquot_scan_active() causing it to call callback for an already deactivated dquot. The race is as follows: CPU1 CPU2 dqput() spin_lock(&dq_list_lock); if (atomic_read(&dquot->dq_count) > 1) { - not taken if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) { spin_unlock(&dq_list_lock); ->release_dquot(dquot); if (atomic_read(&dquot->dq_count) > 1) - not taken dquot_scan_active() spin_lock(&dq_list_lock); if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) - not taken atomic_inc(&dquot->dq_count); spin_unlock(&dq_list_lock); - proceeds to release dquot ret = fn(dquot, priv); - called for inactive dquot Fix the problem by making sure possible ->release_dquot() is finished by the time we call the callback and new calls to it will notice reference dquot_scan_active() has taken and bail out. CC: stable@vger.kernel.org # >= 2.6.29 Signed-off-by: Jan Kara <jack@suse.cz>		2014-02-20 21:57:04 +01:00
..
compat.c
dquot.c	quota: Fix race between dqput() and dquot_scan_active()	2014-02-20 21:57:04 +01:00
Kconfig
kqid.c	userns: Implement struct kqid	2012-09-18 01:01:38 -07:00
Makefile	userns: Implement struct kqid	2012-09-18 01:01:38 -07:00
netlink.c	genetlink: make multicast groups const, prevent abuse	2013-11-19 16:39:06 -05:00
quota_tree.c	userns: Convert struct dquot dq_id to be a struct kqid	2012-09-18 01:01:41 -07:00
quota_tree.h
quota_v1.c	userns: Convert struct dquot dq_id to be a struct kqid	2012-09-18 01:01:41 -07:00
quota_v2.c	userns: Convert struct dquot dq_id to be a struct kqid	2012-09-18 01:01:41 -07:00
quota.c	quota: info leak in quota_getquota()	2013-11-04 14:16:55 +01:00
quotaio_v1.h
quotaio_v2.h