[PATCH net -v2] [BUGFIX] bonding: use flush_delayed_work_sync in bond_close
From: Mitsuo Hayasaka <hidden>
Date: 2011-10-19 08:12:43
Also in:
lkml
Subsystem:
bonding driver, networking drivers, the rest · Maintainers:
Jay Vosburgh, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
The bond_close() calls cancel_delayed_work() to cancel delayed works. It, however, cannot cancel works that were already queued in workqueue. The bond_open() initializes work->data, and proccess_one_work() refers get_work_cwq(work)->wq->flags. The get_work_cwq() returns NULL when work->data has been initialized. Thus, a panic occurs. This patch uses flush_delayed_work_sync() instead of cancel_delayed_work() in bond_close(). It cancels delayed timer and waits for work to finish execution. So, it can avoid the null pointer dereference due to the parallel executions of proccess_one_work() and initializing proccess of bond_open(). Signed-off-by: Mitsuo Hayasaka <redacted> Reviewed-by: WANG Cong <redacted> Cc: Jay Vosburgh <redacted> Cc: Andy Gospodarek <andy@greyhouse.net> Cc: WANG Cong <redacted> --- drivers/net/bonding/bond_main.c | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index de3d351..a4353f9 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c@@ -3504,27 +3504,27 @@ static int bond_close(struct net_device *bond_dev) write_unlock_bh(&bond->lock); if (bond->params.miimon) { /* link check interval, in milliseconds. */ - cancel_delayed_work(&bond->mii_work); + flush_delayed_work_sync(&bond->mii_work); } if (bond->params.arp_interval) { /* arp interval, in milliseconds. */ - cancel_delayed_work(&bond->arp_work); + flush_delayed_work_sync(&bond->arp_work); } switch (bond->params.mode) { case BOND_MODE_8023AD: - cancel_delayed_work(&bond->ad_work); + flush_delayed_work_sync(&bond->ad_work); break; case BOND_MODE_TLB: case BOND_MODE_ALB: - cancel_delayed_work(&bond->alb_work); + flush_delayed_work_sync(&bond->alb_work); break; default: break; } if (delayed_work_pending(&bond->mcast_work)) - cancel_delayed_work(&bond->mcast_work); + flush_delayed_work_sync(&bond->mcast_work); if (bond_is_lb(bond)) { /* Must be called only after all