The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3116f59c12bd24c513194cd3acb3ec1f7d468954 Mon Sep 17 00:00:00 2001 From: Di Zhu zhudi2@huawei.com Date: Mon, 29 Nov 2021 19:52:01 +0600 Subject: [PATCH] i40e: fix use-after-free in i40e_sync_filters_subtask()

Using ifconfig command to delete the ipv6 address will cause the i40e network card driver to delete its internal mac_filter and i40e_service_task kernel thread will concurrently access the mac_filter. These two processes are not protected by lock so causing the following use-after-free problems.

print_address_description+0x70/0x360 ? vprintk_func+0x5e/0xf0 kasan_report+0x1b2/0x330 i40e_sync_vsi_filters+0x4f0/0x1850 [i40e] i40e_sync_filters_subtask+0xe3/0x130 [i40e] i40e_service_task+0x195/0x24c0 [i40e] process_one_work+0x3f5/0x7d0 worker_thread+0x61/0x6c0 ? process_one_work+0x7d0/0x7d0 kthread+0x1c3/0x1f0 ? kthread_park+0xc0/0xc0 ret_from_fork+0x35/0x40

Allocated by task 2279810: kasan_kmalloc+0xa0/0xd0 kmem_cache_alloc_trace+0xf3/0x1e0 i40e_add_filter+0x127/0x2b0 [i40e] i40e_add_mac_filter+0x156/0x190 [i40e] i40e_addr_sync+0x2d/0x40 [i40e] __hw_addr_sync_dev+0x154/0x210 i40e_set_rx_mode+0x6d/0xf0 [i40e] __dev_set_rx_mode+0xfb/0x1f0 __dev_mc_add+0x6c/0x90 igmp6_group_added+0x214/0x230 __ipv6_dev_mc_inc+0x338/0x4f0 addrconf_join_solict.part.7+0xa2/0xd0 addrconf_dad_work+0x500/0x980 process_one_work+0x3f5/0x7d0 worker_thread+0x61/0x6c0 kthread+0x1c3/0x1f0 ret_from_fork+0x35/0x40

Freed by task 2547073: __kasan_slab_free+0x130/0x180 kfree+0x90/0x1b0 __i40e_del_filter+0xa3/0xf0 [i40e] i40e_del_mac_filter+0xf3/0x130 [i40e] i40e_addr_unsync+0x85/0xa0 [i40e] __hw_addr_sync_dev+0x9d/0x210 i40e_set_rx_mode+0x6d/0xf0 [i40e] __dev_set_rx_mode+0xfb/0x1f0 __dev_mc_del+0x69/0x80 igmp6_group_dropped+0x279/0x510 __ipv6_dev_mc_dec+0x174/0x220 addrconf_leave_solict.part.8+0xa2/0xd0 __ipv6_ifa_notify+0x4cd/0x570 ipv6_ifa_notify+0x58/0x80 ipv6_del_addr+0x259/0x4a0 inet6_addr_del+0x188/0x260 addrconf_del_ifaddr+0xcc/0x130 inet6_ioctl+0x152/0x190 sock_do_ioctl+0xd8/0x2b0 sock_ioctl+0x2e5/0x4c0 do_vfs_ioctl+0x14e/0xa80 ksys_ioctl+0x7c/0xa0 __x64_sys_ioctl+0x42/0x50 do_syscall_64+0x98/0x2c0 entry_SYSCALL_64_after_hwframe+0x65/0xca

Fixes: 41c445ff0f48 ("i40e: main driver core") Signed-off-by: Di Zhu zhudi2@huawei.com Signed-off-by: Rui Zhang zhangrui182@huawei.com Tested-by: Gurucharan G gurucharanx.g@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index e118cf9265c7..e0c4d6113c02 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -99,6 +99,24 @@ MODULE_LICENSE("GPL v2");

static struct workqueue_struct *i40e_wq;

+static void netdev_hw_addr_refcnt(struct i40e_mac_filter *f, + struct net_device *netdev, int delta) +{ + struct netdev_hw_addr *ha; + + if (!f || !netdev) + return; + + netdev_for_each_mc_addr(ha, netdev) { + if (ether_addr_equal(ha->addr, f->macaddr)) { + ha->refcount += delta; + if (ha->refcount <= 0) + ha->refcount = 1; + break; + } + } +} + /** * i40e_allocate_dma_mem_d - OS specific memory alloc for shared code * @hw: pointer to the HW structure @@ -2036,6 +2054,7 @@ static void i40e_undo_add_filter_entries(struct i40e_vsi *vsi, hlist_for_each_entry_safe(new, h, from, hlist) { /* We can simply free the wrapper structure */ hlist_del(&new->hlist); + netdev_hw_addr_refcnt(new->f, vsi->netdev, -1); kfree(new); } } @@ -2383,6 +2402,10 @@ int i40e_sync_vsi_filters(struct i40e_vsi *vsi) &tmp_add_list, &tmp_del_list, vlan_filters); + + hlist_for_each_entry(new, &tmp_add_list, hlist) + netdev_hw_addr_refcnt(new->f, vsi->netdev, 1); + if (retval) goto err_no_memory_locked;

@@ -2515,6 +2538,7 @@ int i40e_sync_vsi_filters(struct i40e_vsi *vsi) if (new->f->state == I40E_FILTER_NEW) new->f->state = new->state; hlist_del(&new->hlist); + netdev_hw_addr_refcnt(new->f, vsi->netdev, -1); kfree(new); } spin_unlock_bh(&vsi->mac_filter_hash_lock);