IB/IPoIB: Fix kernel panic on multicast flow

ipoib_mcast_restart_task calls ipoib_mcast_remove_list with the
parameter mcast->dev. That mcast is a temporary (used as an iterator)
variable that may be uninitialized.
There is no need to send the variable dev to the function, as each mcast
has its dev as a member in the mcast struct.

This causes the next panic:
RIP: 0010: ipoib_mcast_leave+0x6d/0xf0 [ib_ipoib]
RSP: 0018: EFLAGS: 00010246
RAX: f0201 RBX: 24e00 RCX: 00000
....
....
Stack:
Call Trace:
	ipoib_mcast_remove_list+0x3a/0x70 [ib_ipoib]
	ipoib_mcast_restart_task+0x3bb/0x520 [ib_ipoib]
	process_one_work+0x164/0x470
	worker_thread+0x11d/0x420
	...

Fixes: 5a0e81f6f483 ('IB/IPoIB: factor out common multicast list removal code')
Signed-off-by: Erez Shitrit <erezsh@mellanox.com>
Reported-by: Doron Tsur <doront@mellanox.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index a924933..a6f3eab 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -548,7 +548,7 @@ void ipoib_path_iter_read(struct ipoib_path_iter *iter,
 
 int ipoib_mcast_attach(struct net_device *dev, u16 mlid,
                       union ib_gid *mgid, int set_qkey);
-void ipoib_mcast_remove_list(struct net_device *dev, struct list_head *remove_list);
+void ipoib_mcast_remove_list(struct list_head *remove_list);
 void ipoib_check_and_add_mcast_sendonly(struct ipoib_dev_priv *priv, u8 *mgid,
                                struct list_head *remove_list);
 

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 0a93cb2..25509bb 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -1150,7 +1150,6 @@ static void __ipoib_reap_neigh(struct ipoib_dev_priv *priv)
        unsigned long flags;
        int i;
        LIST_HEAD(remove_list);
-       struct net_device *dev = priv->dev;
 
        if (test_bit(IPOIB_STOP_NEIGH_GC, &priv->flags))
                return;
@@ -1196,7 +1195,7 @@ static void __ipoib_reap_neigh(struct ipoib_dev_priv *priv)
 
 out_unlock:
        spin_unlock_irqrestore(&priv->lock, flags);
-       ipoib_mcast_remove_list(dev, &remove_list);
+       ipoib_mcast_remove_list(&remove_list);
 }
 
 static void ipoib_reap_neigh(struct work_struct *work)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
index ab79b87..050dfa1 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
@@ -723,12 +723,12 @@ void ipoib_check_and_add_mcast_sendonly(struct ipoib_dev_priv *priv, u8 *mgid,
        }
 }
 
-void ipoib_mcast_remove_list(struct net_device *dev, struct list_head *remove_list)
+void ipoib_mcast_remove_list(struct list_head *remove_list)
 {
        struct ipoib_mcast *mcast, *tmcast;
 
        list_for_each_entry_safe(mcast, tmcast, remove_list, list) {
-               ipoib_mcast_leave(dev, mcast);
+               ipoib_mcast_leave(mcast->dev, mcast);
                ipoib_mcast_free(mcast);
        }
 }
@@ -839,7 +839,7 @@ void ipoib_mcast_dev_flush(struct net_device *dev)
                if (test_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags))
                        wait_for_completion(&mcast->done);
 
-       ipoib_mcast_remove_list(dev, &remove_list);
+       ipoib_mcast_remove_list(&remove_list);
 }
 
 static int ipoib_mcast_addr_is_valid(const u8 *addr, const u8 *broadcast)
@@ -965,7 +965,7 @@ void ipoib_mcast_restart_task(struct work_struct *work)
                if (test_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags))
                        wait_for_completion(&mcast->done);
 
-       ipoib_mcast_remove_list(mcast->dev, &remove_list);
+       ipoib_mcast_remove_list(&remove_list);
 
        /*
         * Double check that we are still up