linux/net/8021q
Eric Dumazet 72a0b32911 vlan: fix memory leak in vlan_newlink()
Blamed commit added back a bug I fixed in commit 9bbd917e0b
("vlan: fix memory leak in vlan_dev_set_egress_priority")

If a memory allocation fails in vlan_changelink() after other allocations
succeeded, we need to call vlan_dev_free_egress_priority()
to free all allocated memory because after a failed ->newlink()
we do not call any methods like ndo_uninit() or dev->priv_destructor().

In following example, if the allocation for last element 2000:2001 fails,
we need to free eight prior allocations:

ip link add link dummy0 dummy0.100 type vlan id 100 \
	egress-qos-map 1:2 2:3 3:4 4:5 5:6 6:7 7:8 8:9 2000:2001

syzbot report was:

BUG: memory leak
unreferenced object 0xffff888117bd1060 (size 32):
comm "syz-executor408", pid 3759, jiffies 4294956555 (age 34.090s)
hex dump (first 32 bytes):
09 00 00 00 00 a0 00 00 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:
[<ffffffff83fc60ad>] kmalloc include/linux/slab.h:600 [inline]
[<ffffffff83fc60ad>] vlan_dev_set_egress_priority+0xed/0x170 net/8021q/vlan_dev.c:193
[<ffffffff83fc6628>] vlan_changelink+0x178/0x1d0 net/8021q/vlan_netlink.c:128
[<ffffffff83fc67c8>] vlan_newlink+0x148/0x260 net/8021q/vlan_netlink.c:185
[<ffffffff838b1278>] rtnl_newlink_create net/core/rtnetlink.c:3363 [inline]
[<ffffffff838b1278>] __rtnl_newlink+0xa58/0xdc0 net/core/rtnetlink.c:3580
[<ffffffff838b1629>] rtnl_newlink+0x49/0x70 net/core/rtnetlink.c:3593
[<ffffffff838ac66c>] rtnetlink_rcv_msg+0x21c/0x5c0 net/core/rtnetlink.c:6089
[<ffffffff839f9c37>] netlink_rcv_skb+0x87/0x1d0 net/netlink/af_netlink.c:2501
[<ffffffff839f8da7>] netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
[<ffffffff839f8da7>] netlink_unicast+0x397/0x4c0 net/netlink/af_netlink.c:1345
[<ffffffff839f9266>] netlink_sendmsg+0x396/0x710 net/netlink/af_netlink.c:1921
[<ffffffff8384dbf6>] sock_sendmsg_nosec net/socket.c:714 [inline]
[<ffffffff8384dbf6>] sock_sendmsg+0x56/0x80 net/socket.c:734
[<ffffffff8384e15c>] ____sys_sendmsg+0x36c/0x390 net/socket.c:2488
[<ffffffff838523cb>] ___sys_sendmsg+0x8b/0xd0 net/socket.c:2542
[<ffffffff838525b8>] __sys_sendmsg net/socket.c:2571 [inline]
[<ffffffff838525b8>] __do_sys_sendmsg net/socket.c:2580 [inline]
[<ffffffff838525b8>] __se_sys_sendmsg net/socket.c:2578 [inline]
[<ffffffff838525b8>] __x64_sys_sendmsg+0x78/0xf0 net/socket.c:2578
[<ffffffff845ad8d5>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff845ad8d5>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff8460006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: 37aa50c539 ("vlan: introduce vlan_dev_free_egress_priority")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-09 12:26:59 +01:00
..
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile net: remove blank lines at end of file 2018-07-24 14:10:43 -07:00
vlan_core.c gro: remove rcu_read_lock/rcu_read_unlock from gro_complete handlers 2021-11-24 17:21:42 -08:00
vlan_dev.c net: add netif_inherit_tso_max() 2022-05-06 12:07:56 +01:00
vlan_gvrp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
vlan_mvrp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
vlan_netlink.c vlan: fix memory leak in vlan_newlink() 2022-07-09 12:26:59 +01:00
vlan.c net: add netif_inherit_tso_max() 2022-05-06 12:07:56 +01:00
vlan.h vlan: introduce vlan_dev_free_egress_priority 2022-02-09 13:33:39 +00:00
vlanproc.c vlan: use correct format characters 2022-03-17 16:34:49 -07:00
vlanproc.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00