Messages in this thread Patch in this message | | | From | Lin Ma <> | Subject | [PATCH v0] idb: Add rtnl_lock to avoid data race | Date | Mon, 8 Aug 2022 16:10:50 +0800 |
| |
The commit c23d92b80e0b ("igb: Teardown SR-IOV before unregister_netdev()") places the unregister_netdev() call after the igb_disable_sriov() call to avoid functionality issue.
However, it introduces several race conditions when detaching a device. For example, when .remove() is called, the below interleaving leads to use-after-free.
(FREE from device detaching) | (USE from netdev core) igb_remove | igb_ndo_get_vf_config igb_disable_sriov | vf >= adapter->vfs_allocated_count? kfree(adapter->vf_data) | adapter->vfs_allocated_count = 0 | | memcpy(... adapter->vf_data[vf]
In short, there are data races between read and write of adapter->vfs_allocated_count. To fix this, we can add a new lock to protect members in adapter object. However, we cau use the existing rtnl_lock just as other drivers do. (See how dpaa2_eth_disconnect_mac is protected in dpaa2_eth_remove function). This patch adopts similar fixes.
Fixes: c23d92b80e0b ("igb: Teardown SR-IOV before unregister_netdev()") Signed-off-by: Lin Ma <linma@zju.edu.cn> --- drivers/net/ethernet/intel/igb/igb_main.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index d8b836a85cc3..e86ea4de05f8 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -3814,7 +3814,9 @@ static void igb_remove(struct pci_dev *pdev) igb_release_hw_control(adapter); #ifdef CONFIG_PCI_IOV + rtnl_lock(); igb_disable_sriov(pdev); + rtnl_unlock(); #endif unregister_netdev(netdev); -- 2.36.1
| |