Message ID | 20200715014930.323472-1-chenweilong@huawei.com |
---|---|
State | Changes Requested |
Delegated to: | David Miller |
Headers | show |
Series | [v4,net] rtnetlink: Fix memory(net_device) leak when ->newlink fails | expand |
On Tue, Jul 14, 2020 at 6:27 PM Weilong Chen <chenweilong@huawei.com> wrote: > > When vlan_newlink call register_vlan_dev fails, it might return error > with dev->reg_state = NETREG_UNREGISTERED. The rtnl_newlink should > free the memory. But currently rtnl_newlink only free the memory which > state is NETREG_UNINITIALIZED. > > BUG: memory leak > unreferenced object 0xffff8881051de000 (size 4096): > comm "syz-executor139", pid 560, jiffies 4294745346 (age 32.445s) > hex dump (first 32 bytes): > 76 6c 61 6e 32 00 00 00 00 00 00 00 00 00 00 00 vlan2........... > 00 45 28 03 81 88 ff ff 00 00 00 00 00 00 00 00 .E(............. > backtrace: > [<0000000047527e31>] kmalloc_node include/linux/slab.h:578 [inline] > [<0000000047527e31>] kvmalloc_node+0x33/0xd0 mm/util.c:574 > [<000000002b59e3bc>] kvmalloc include/linux/mm.h:753 [inline] > [<000000002b59e3bc>] kvzalloc include/linux/mm.h:761 [inline] > [<000000002b59e3bc>] alloc_netdev_mqs+0x83/0xd90 net/core/dev.c:9929 > [<000000006076752a>] rtnl_create_link+0x2c0/0xa20 net/core/rtnetlink.c:3067 > [<00000000572b3be5>] __rtnl_newlink+0xc9c/0x1330 net/core/rtnetlink.c:3329 > [<00000000e84ea553>] rtnl_newlink+0x66/0x90 net/core/rtnetlink.c:3397 > [<0000000052c7c0a9>] rtnetlink_rcv_msg+0x540/0x990 net/core/rtnetlink.c:5460 > [<000000004b5cb379>] netlink_rcv_skb+0x12b/0x3a0 net/netlink/af_netlink.c:2469 > [<00000000c71c20d3>] netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] > [<00000000c71c20d3>] netlink_unicast+0x4c6/0x690 net/netlink/af_netlink.c:1329 > [<00000000cca72fa9>] netlink_sendmsg+0x735/0xcc0 net/netlink/af_netlink.c:1918 > [<000000009221ebf7>] sock_sendmsg_nosec net/socket.c:652 [inline] > [<000000009221ebf7>] sock_sendmsg+0x109/0x140 net/socket.c:672 > [<000000001c30ffe4>] ____sys_sendmsg+0x5f5/0x780 net/socket.c:2352 > [<00000000b71ca6f3>] ___sys_sendmsg+0x11d/0x1a0 net/socket.c:2406 > [<0000000007297384>] __sys_sendmsg+0xeb/0x1b0 net/socket.c:2439 > [<000000000eb29b11>] do_syscall_64+0x56/0xa0 arch/x86/entry/common.c:359 > [<000000006839b4d0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Fixes: e51fb152318ee6 ("rtnetlink: fix a memory leak when ->newlink fails") This bug is apparently not introduced by my commit above. It should be commit cb626bf566eb4433318d35681286c494f0, right? That commit introduced NETREG_UNREGISTERED on the path.
On 2020/7/15 13:45, Cong Wang wrote: > On Tue, Jul 14, 2020 at 6:27 PM Weilong Chen <chenweilong@huawei.com> wrote: >> >> When vlan_newlink call register_vlan_dev fails, it might return error >> with dev->reg_state = NETREG_UNREGISTERED. The rtnl_newlink should >> free the memory. But currently rtnl_newlink only free the memory which >> state is NETREG_UNINITIALIZED. >> >> BUG: memory leak >> unreferenced object 0xffff8881051de000 (size 4096): >> comm "syz-executor139", pid 560, jiffies 4294745346 (age 32.445s) >> hex dump (first 32 bytes): >> 76 6c 61 6e 32 00 00 00 00 00 00 00 00 00 00 00 vlan2........... >> 00 45 28 03 81 88 ff ff 00 00 00 00 00 00 00 00 .E(............. >> backtrace: >> [<0000000047527e31>] kmalloc_node include/linux/slab.h:578 [inline] >> [<0000000047527e31>] kvmalloc_node+0x33/0xd0 mm/util.c:574 >> [<000000002b59e3bc>] kvmalloc include/linux/mm.h:753 [inline] >> [<000000002b59e3bc>] kvzalloc include/linux/mm.h:761 [inline] >> [<000000002b59e3bc>] alloc_netdev_mqs+0x83/0xd90 net/core/dev.c:9929 >> [<000000006076752a>] rtnl_create_link+0x2c0/0xa20 net/core/rtnetlink.c:3067 >> [<00000000572b3be5>] __rtnl_newlink+0xc9c/0x1330 net/core/rtnetlink.c:3329 >> [<00000000e84ea553>] rtnl_newlink+0x66/0x90 net/core/rtnetlink.c:3397 >> [<0000000052c7c0a9>] rtnetlink_rcv_msg+0x540/0x990 net/core/rtnetlink.c:5460 >> [<000000004b5cb379>] netlink_rcv_skb+0x12b/0x3a0 net/netlink/af_netlink.c:2469 >> [<00000000c71c20d3>] netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] >> [<00000000c71c20d3>] netlink_unicast+0x4c6/0x690 net/netlink/af_netlink.c:1329 >> [<00000000cca72fa9>] netlink_sendmsg+0x735/0xcc0 net/netlink/af_netlink.c:1918 >> [<000000009221ebf7>] sock_sendmsg_nosec net/socket.c:652 [inline] >> [<000000009221ebf7>] sock_sendmsg+0x109/0x140 net/socket.c:672 >> [<000000001c30ffe4>] ____sys_sendmsg+0x5f5/0x780 net/socket.c:2352 >> [<00000000b71ca6f3>] ___sys_sendmsg+0x11d/0x1a0 net/socket.c:2406 >> [<0000000007297384>] __sys_sendmsg+0xeb/0x1b0 net/socket.c:2439 >> [<000000000eb29b11>] do_syscall_64+0x56/0xa0 arch/x86/entry/common.c:359 >> [<000000006839b4d0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 >> >> Fixes: e51fb152318ee6 ("rtnetlink: fix a memory leak when ->newlink fails") > > This bug is apparently not introduced by my commit above. > > It should be commit cb626bf566eb4433318d35681286c494f0, > right? That commit introduced NETREG_UNREGISTERED on the path. > Yes, you'er right, I'll resubmit. Thanks. > . >
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 9aedc15736ad..85a4b0101f76 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3343,7 +3343,8 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, */ if (err < 0) { /* If device is not registered at all, free it now */ - if (dev->reg_state == NETREG_UNINITIALIZED) + if (dev->reg_state == NETREG_UNINITIALIZED || + dev->reg_state == NETREG_UNREGISTERED) free_netdev(dev); goto out; }