Commit ef1100ef authored by Arun Ramadoss's avatar Arun Ramadoss Committed by David S. Miller

net: dsa: microchip: Added the condition for scheduling ksz_mib_read_work

When the ksz module is installed and removed using rmmod, kernel crashes
with null pointer dereferrence error. During rmmod, ksz_switch_remove
function tries to cancel the mib_read_workqueue using
cancel_delayed_work_sync routine and unregister switch from dsa.

During dsa_unregister_switch it calls ksz_mac_link_down, which in turn
reschedules the workqueue since mib_interval is non-zero.
Due to which queue executed after mib_interval and it tries to access
dp->slave. But the slave is unregistered in the ksz_switch_remove
function. Hence kernel crashes.

To avoid this crash, before canceling the workqueue, resetted the
mib_interval to 0.

v1 -> v2:
-Removed the if condition in ksz_mib_read_work

Fixes: 469b390e ("net: dsa: microchip: use delayed_work instead of timer + work")
Signed-off-by: default avatarArun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9973a430
...@@ -449,8 +449,10 @@ EXPORT_SYMBOL(ksz_switch_register); ...@@ -449,8 +449,10 @@ EXPORT_SYMBOL(ksz_switch_register);
void ksz_switch_remove(struct ksz_device *dev) void ksz_switch_remove(struct ksz_device *dev)
{ {
/* timer started */ /* timer started */
if (dev->mib_read_interval) if (dev->mib_read_interval) {
dev->mib_read_interval = 0;
cancel_delayed_work_sync(&dev->mib_read); cancel_delayed_work_sync(&dev->mib_read);
}
dev->dev_ops->exit(dev); dev->dev_ops->exit(dev);
dsa_unregister_switch(dev->ds); dsa_unregister_switch(dev->ds);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment