From: Vlad Buslov Date: Tue, 8 Aug 2023 09:35:21 +0000 (+0200) Subject: vlan: Fix VLAN 0 memory leak X-Git-Tag: v6.6.7~2215^2~15 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=718cb09aaa6fa78cc8124e9517efbc6c92665384;p=platform%2Fkernel%2Flinux-starfive.git vlan: Fix VLAN 0 memory leak The referenced commit intended to fix memleak of VLAN 0 that is implicitly created on devices with NETIF_F_HW_VLAN_CTAG_FILTER feature. However, it doesn't take into account that the feature can be re-set during the netdevice lifetime which will cause memory leak if feature is disabled during the device deletion as illustrated by [0]. Fix the leak by unconditionally deleting VLAN 0 on NETDEV_DOWN event. [0]: > modprobe 8021q > ip l set dev eth2 up > ethtool -K eth2 rx-vlan-filter off > modprobe -r mlx5_ib > modprobe -r mlx5_core > cat /sys/kernel/debug/kmemleak unreferenced object 0xffff888103dcd900 (size 256): comm "ip", pid 1490, jiffies 4294907305 (age 325.364s) hex dump (first 32 bytes): 00 80 5d 03 81 88 ff ff 00 00 00 00 00 00 00 00 ..]............. 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000899f3bb9>] kmalloc_trace+0x25/0x80 [<000000002889a7a2>] vlan_vid_add+0xa0/0x210 [<000000007177800e>] vlan_device_event+0x374/0x760 [8021q] [<000000009a0716b1>] notifier_call_chain+0x35/0xb0 [<00000000bbf3d162>] __dev_notify_flags+0x58/0xf0 [<0000000053d2b05d>] dev_change_flags+0x4d/0x60 [<00000000982807e9>] do_setlink+0x28d/0x10a0 [<0000000058c1be00>] __rtnl_newlink+0x545/0x980 [<00000000e66c3bd9>] rtnl_newlink+0x44/0x70 [<00000000a2cc5970>] rtnetlink_rcv_msg+0x29c/0x390 [<00000000d307d1e4>] netlink_rcv_skb+0x54/0x100 [<00000000259d16f9>] netlink_unicast+0x1f6/0x2c0 [<000000007ce2afa1>] netlink_sendmsg+0x232/0x4a0 [<00000000f3f4bb39>] sock_sendmsg+0x38/0x60 [<000000002f9c0624>] ____sys_sendmsg+0x1e3/0x200 [<00000000d6ff5520>] ___sys_sendmsg+0x80/0xc0 unreferenced object 0xffff88813354fde0 (size 32): comm "ip", pid 1490, jiffies 4294907305 (age 325.364s) hex dump (first 32 bytes): a0 d9 dc 03 81 88 ff ff a0 d9 dc 03 81 88 ff ff ................ 81 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000899f3bb9>] kmalloc_trace+0x25/0x80 [<000000002da64724>] vlan_vid_add+0xdf/0x210 [<000000007177800e>] vlan_device_event+0x374/0x760 [8021q] [<000000009a0716b1>] notifier_call_chain+0x35/0xb0 [<00000000bbf3d162>] __dev_notify_flags+0x58/0xf0 [<0000000053d2b05d>] dev_change_flags+0x4d/0x60 [<00000000982807e9>] do_setlink+0x28d/0x10a0 [<0000000058c1be00>] __rtnl_newlink+0x545/0x980 [<00000000e66c3bd9>] rtnl_newlink+0x44/0x70 [<00000000a2cc5970>] rtnetlink_rcv_msg+0x29c/0x390 [<00000000d307d1e4>] netlink_rcv_skb+0x54/0x100 [<00000000259d16f9>] netlink_unicast+0x1f6/0x2c0 [<000000007ce2afa1>] netlink_sendmsg+0x232/0x4a0 [<00000000f3f4bb39>] sock_sendmsg+0x38/0x60 [<000000002f9c0624>] ____sys_sendmsg+0x1e3/0x200 [<00000000d6ff5520>] ___sys_sendmsg+0x80/0xc0 Fixes: efc73f4bbc23 ("net: Fix memory leak - vlan_info struct") Reviewed-by: Ido Schimmel Signed-off-by: Vlad Buslov Link: https://lore.kernel.org/r/20230808093521.1468929-1-vladbu@nvidia.com Signed-off-by: Jakub Kicinski --- diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c index e40aa3e3641c..b3662119ddbc 100644 --- a/net/8021q/vlan.c +++ b/net/8021q/vlan.c @@ -384,8 +384,7 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event, dev->name); vlan_vid_add(dev, htons(ETH_P_8021Q), 0); } - if (event == NETDEV_DOWN && - (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)) + if (event == NETDEV_DOWN) vlan_vid_del(dev, htons(ETH_P_8021Q), 0); vlan_info = rtnl_dereference(dev->vlan_info);