[net] net: openvswitch: free vport unless register_netdevice() succeeds
diff mbox series

Message ID 3caa233b136b5104c817a52a5fdc02691e530528.1571651489.git.sbrivio@redhat.com
State Accepted
Delegated to: David Miller
Headers show
Series
  • [net] net: openvswitch: free vport unless register_netdevice() succeeds
Related show

Commit Message

Stefano Brivio Oct. 21, 2019, 10:01 a.m. UTC
From: Hillf Danton <hdanton@sina.com>

syzbot found the following crash on:

HEAD commit:    1e78030e Merge tag 'mmc-v5.3-rc1' of git://git.kernel.org/..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=148d3d1a600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=30cef20daf3e9977
dashboard link: https://syzkaller.appspot.com/bug?extid=13210896153522fe1ee5
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=136aa8c4600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=109ba792600000

=====================================================================
BUG: memory leak
unreferenced object 0xffff8881207e4100 (size 128):
   comm "syz-executor032", pid 7014, jiffies 4294944027 (age 13.830s)
   hex dump (first 32 bytes):
     00 70 16 18 81 88 ff ff 80 af 8c 22 81 88 ff ff  .p........."....
     00 b6 23 17 81 88 ff ff 00 00 00 00 00 00 00 00  ..#.............
   backtrace:
     [<000000000eb78212>] kmemleak_alloc_recursive  include/linux/kmemleak.h:43 [inline]
     [<000000000eb78212>] slab_post_alloc_hook mm/slab.h:522 [inline]
     [<000000000eb78212>] slab_alloc mm/slab.c:3319 [inline]
     [<000000000eb78212>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
     [<00000000006ea6c6>] kmalloc include/linux/slab.h:552 [inline]
     [<00000000006ea6c6>] kzalloc include/linux/slab.h:748 [inline]
     [<00000000006ea6c6>] ovs_vport_alloc+0x37/0xf0  net/openvswitch/vport.c:130
     [<00000000f9a04a7d>] internal_dev_create+0x24/0x1d0  net/openvswitch/vport-internal_dev.c:164
     [<0000000056ee7c13>] ovs_vport_add+0x81/0x190  net/openvswitch/vport.c:199
     [<000000005434efc7>] new_vport+0x19/0x80 net/openvswitch/datapath.c:194
     [<00000000b7b253f1>] ovs_dp_cmd_new+0x22f/0x410  net/openvswitch/datapath.c:1614
     [<00000000e0988518>] genl_family_rcv_msg+0x2ab/0x5b0  net/netlink/genetlink.c:629
     [<00000000d0cc9347>] genl_rcv_msg+0x54/0x9c net/netlink/genetlink.c:654
     [<000000006694b647>] netlink_rcv_skb+0x61/0x170  net/netlink/af_netlink.c:2477
     [<0000000088381f37>] genl_rcv+0x29/0x40 net/netlink/genetlink.c:665
     [<00000000dad42a47>] netlink_unicast_kernel  net/netlink/af_netlink.c:1302 [inline]
     [<00000000dad42a47>] netlink_unicast+0x1ec/0x2d0  net/netlink/af_netlink.c:1328
     [<0000000067e6b079>] netlink_sendmsg+0x270/0x480  net/netlink/af_netlink.c:1917
     [<00000000aab08a47>] sock_sendmsg_nosec net/socket.c:637 [inline]
     [<00000000aab08a47>] sock_sendmsg+0x54/0x70 net/socket.c:657
     [<000000004cb7c11d>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2311
     [<00000000c4901c63>] __sys_sendmsg+0x80/0xf0 net/socket.c:2356
     [<00000000c10abb2d>] __do_sys_sendmsg net/socket.c:2365 [inline]
     [<00000000c10abb2d>] __se_sys_sendmsg net/socket.c:2363 [inline]
     [<00000000c10abb2d>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2363

BUG: memory leak
unreferenced object 0xffff88811723b600 (size 64):
   comm "syz-executor032", pid 7014, jiffies 4294944027 (age 13.830s)
   hex dump (first 32 bytes):
     01 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00  ................
     00 00 00 00 00 00 00 00 02 00 00 00 05 35 82 c1  .............5..
   backtrace:
     [<00000000352f46d8>] kmemleak_alloc_recursive  include/linux/kmemleak.h:43 [inline]
     [<00000000352f46d8>] slab_post_alloc_hook mm/slab.h:522 [inline]
     [<00000000352f46d8>] slab_alloc mm/slab.c:3319 [inline]
     [<00000000352f46d8>] __do_kmalloc mm/slab.c:3653 [inline]
     [<00000000352f46d8>] __kmalloc+0x169/0x300 mm/slab.c:3664
     [<000000008e48f3d1>] kmalloc include/linux/slab.h:557 [inline]
     [<000000008e48f3d1>] ovs_vport_set_upcall_portids+0x54/0xd0  net/openvswitch/vport.c:343
     [<00000000541e4f4a>] ovs_vport_alloc+0x7f/0xf0  net/openvswitch/vport.c:139
     [<00000000f9a04a7d>] internal_dev_create+0x24/0x1d0  net/openvswitch/vport-internal_dev.c:164
     [<0000000056ee7c13>] ovs_vport_add+0x81/0x190  net/openvswitch/vport.c:199
     [<000000005434efc7>] new_vport+0x19/0x80 net/openvswitch/datapath.c:194
     [<00000000b7b253f1>] ovs_dp_cmd_new+0x22f/0x410  net/openvswitch/datapath.c:1614
     [<00000000e0988518>] genl_family_rcv_msg+0x2ab/0x5b0  net/netlink/genetlink.c:629
     [<00000000d0cc9347>] genl_rcv_msg+0x54/0x9c net/netlink/genetlink.c:654
     [<000000006694b647>] netlink_rcv_skb+0x61/0x170  net/netlink/af_netlink.c:2477
     [<0000000088381f37>] genl_rcv+0x29/0x40 net/netlink/genetlink.c:665
     [<00000000dad42a47>] netlink_unicast_kernel  net/netlink/af_netlink.c:1302 [inline]
     [<00000000dad42a47>] netlink_unicast+0x1ec/0x2d0  net/netlink/af_netlink.c:1328
     [<0000000067e6b079>] netlink_sendmsg+0x270/0x480  net/netlink/af_netlink.c:1917
     [<00000000aab08a47>] sock_sendmsg_nosec net/socket.c:637 [inline]
     [<00000000aab08a47>] sock_sendmsg+0x54/0x70 net/socket.c:657
     [<000000004cb7c11d>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2311
     [<00000000c4901c63>] __sys_sendmsg+0x80/0xf0 net/socket.c:2356

BUG: memory leak
unreferenced object 0xffff8881228ca500 (size 128):
   comm "syz-executor032", pid 7015, jiffies 4294944622 (age 7.880s)
   hex dump (first 32 bytes):
     00 f0 27 18 81 88 ff ff 80 ac 8c 22 81 88 ff ff  ..'........"....
     40 b7 23 17 81 88 ff ff 00 00 00 00 00 00 00 00  @.#.............
   backtrace:
     [<000000000eb78212>] kmemleak_alloc_recursive  include/linux/kmemleak.h:43 [inline]
     [<000000000eb78212>] slab_post_alloc_hook mm/slab.h:522 [inline]
     [<000000000eb78212>] slab_alloc mm/slab.c:3319 [inline]
     [<000000000eb78212>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
     [<00000000006ea6c6>] kmalloc include/linux/slab.h:552 [inline]
     [<00000000006ea6c6>] kzalloc include/linux/slab.h:748 [inline]
     [<00000000006ea6c6>] ovs_vport_alloc+0x37/0xf0  net/openvswitch/vport.c:130
     [<00000000f9a04a7d>] internal_dev_create+0x24/0x1d0  net/openvswitch/vport-internal_dev.c:164
     [<0000000056ee7c13>] ovs_vport_add+0x81/0x190  net/openvswitch/vport.c:199
     [<000000005434efc7>] new_vport+0x19/0x80 net/openvswitch/datapath.c:194
     [<00000000b7b253f1>] ovs_dp_cmd_new+0x22f/0x410  net/openvswitch/datapath.c:1614
     [<00000000e0988518>] genl_family_rcv_msg+0x2ab/0x5b0  net/netlink/genetlink.c:629
     [<00000000d0cc9347>] genl_rcv_msg+0x54/0x9c net/netlink/genetlink.c:654
     [<000000006694b647>] netlink_rcv_skb+0x61/0x170  net/netlink/af_netlink.c:2477
     [<0000000088381f37>] genl_rcv+0x29/0x40 net/netlink/genetlink.c:665
     [<00000000dad42a47>] netlink_unicast_kernel  net/netlink/af_netlink.c:1302 [inline]
     [<00000000dad42a47>] netlink_unicast+0x1ec/0x2d0  net/netlink/af_netlink.c:1328
     [<0000000067e6b079>] netlink_sendmsg+0x270/0x480  net/netlink/af_netlink.c:1917
     [<00000000aab08a47>] sock_sendmsg_nosec net/socket.c:637 [inline]
     [<00000000aab08a47>] sock_sendmsg+0x54/0x70 net/socket.c:657
     [<000000004cb7c11d>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2311
     [<00000000c4901c63>] __sys_sendmsg+0x80/0xf0 net/socket.c:2356
     [<00000000c10abb2d>] __do_sys_sendmsg net/socket.c:2365 [inline]
     [<00000000c10abb2d>] __se_sys_sendmsg net/socket.c:2363 [inline]
     [<00000000c10abb2d>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2363
=====================================================================

The function in net core, register_netdevice(), may fail with vport's
destruction callback either invoked or not. After commit 309b66970ee2,
the duty to destroy vport is offloaded from the driver OTOH, which ends
up in the memory leak reported.

It is fixed by releasing vport unless device is registered successfully.
To do that, the callback assignment is defered until device is registered.

Reported-by: syzbot+13210896153522fe1ee5@syzkaller.appspotmail.com
Fixes: 309b66970ee2 ("net: openvswitch: do not free vport if register_netdevice() is failed.")
Cc: Taehee Yoo <ap420073@gmail.com>
Cc: Greg Rose <gvrose8192@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
[sbrivio: this was sent to dev@openvswitch.org and never made its way
 to netdev -- resending original patch]
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
This patch was sent to dev@openvswitch.org and appeared on netdev
only as Pravin replied to it, giving his Acked-by. I contacted the
original author one month ago requesting to resend this to netdev,
but didn't get an answer, so I'm now resending the original patch.

 net/openvswitch/vport-internal_dev.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

Comments

Gregory Rose Oct. 21, 2019, 8:21 p.m. UTC | #1
On 10/21/2019 3:01 AM, Stefano Brivio wrote:
> From: Hillf Danton <hdanton@sina.com>
>
> syzbot found the following crash on:
>
> HEAD commit:    1e78030e Merge tag 'mmc-v5.3-rc1' of git://git.kernel.org/..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=148d3d1a600000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=30cef20daf3e9977
> dashboard link: https://syzkaller.appspot.com/bug?extid=13210896153522fe1ee5
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=136aa8c4600000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=109ba792600000
>
> =====================================================================
> BUG: memory leak
> unreferenced object 0xffff8881207e4100 (size 128):
>     comm "syz-executor032", pid 7014, jiffies 4294944027 (age 13.830s)
>     hex dump (first 32 bytes):
>       00 70 16 18 81 88 ff ff 80 af 8c 22 81 88 ff ff  .p........."....
>       00 b6 23 17 81 88 ff ff 00 00 00 00 00 00 00 00  ..#.............
>     backtrace:
>       [<000000000eb78212>] kmemleak_alloc_recursive  include/linux/kmemleak.h:43 [inline]
>       [<000000000eb78212>] slab_post_alloc_hook mm/slab.h:522 [inline]
>       [<000000000eb78212>] slab_alloc mm/slab.c:3319 [inline]
>       [<000000000eb78212>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
>       [<00000000006ea6c6>] kmalloc include/linux/slab.h:552 [inline]
>       [<00000000006ea6c6>] kzalloc include/linux/slab.h:748 [inline]
>       [<00000000006ea6c6>] ovs_vport_alloc+0x37/0xf0  net/openvswitch/vport.c:130
>       [<00000000f9a04a7d>] internal_dev_create+0x24/0x1d0  net/openvswitch/vport-internal_dev.c:164
>       [<0000000056ee7c13>] ovs_vport_add+0x81/0x190  net/openvswitch/vport.c:199
>       [<000000005434efc7>] new_vport+0x19/0x80 net/openvswitch/datapath.c:194
>       [<00000000b7b253f1>] ovs_dp_cmd_new+0x22f/0x410  net/openvswitch/datapath.c:1614
>       [<00000000e0988518>] genl_family_rcv_msg+0x2ab/0x5b0  net/netlink/genetlink.c:629
>       [<00000000d0cc9347>] genl_rcv_msg+0x54/0x9c net/netlink/genetlink.c:654
>       [<000000006694b647>] netlink_rcv_skb+0x61/0x170  net/netlink/af_netlink.c:2477
>       [<0000000088381f37>] genl_rcv+0x29/0x40 net/netlink/genetlink.c:665
>       [<00000000dad42a47>] netlink_unicast_kernel  net/netlink/af_netlink.c:1302 [inline]
>       [<00000000dad42a47>] netlink_unicast+0x1ec/0x2d0  net/netlink/af_netlink.c:1328
>       [<0000000067e6b079>] netlink_sendmsg+0x270/0x480  net/netlink/af_netlink.c:1917
>       [<00000000aab08a47>] sock_sendmsg_nosec net/socket.c:637 [inline]
>       [<00000000aab08a47>] sock_sendmsg+0x54/0x70 net/socket.c:657
>       [<000000004cb7c11d>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2311
>       [<00000000c4901c63>] __sys_sendmsg+0x80/0xf0 net/socket.c:2356
>       [<00000000c10abb2d>] __do_sys_sendmsg net/socket.c:2365 [inline]
>       [<00000000c10abb2d>] __se_sys_sendmsg net/socket.c:2363 [inline]
>       [<00000000c10abb2d>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2363
>
> BUG: memory leak
> unreferenced object 0xffff88811723b600 (size 64):
>     comm "syz-executor032", pid 7014, jiffies 4294944027 (age 13.830s)
>     hex dump (first 32 bytes):
>       01 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00  ................
>       00 00 00 00 00 00 00 00 02 00 00 00 05 35 82 c1  .............5..
>     backtrace:
>       [<00000000352f46d8>] kmemleak_alloc_recursive  include/linux/kmemleak.h:43 [inline]
>       [<00000000352f46d8>] slab_post_alloc_hook mm/slab.h:522 [inline]
>       [<00000000352f46d8>] slab_alloc mm/slab.c:3319 [inline]
>       [<00000000352f46d8>] __do_kmalloc mm/slab.c:3653 [inline]
>       [<00000000352f46d8>] __kmalloc+0x169/0x300 mm/slab.c:3664
>       [<000000008e48f3d1>] kmalloc include/linux/slab.h:557 [inline]
>       [<000000008e48f3d1>] ovs_vport_set_upcall_portids+0x54/0xd0  net/openvswitch/vport.c:343
>       [<00000000541e4f4a>] ovs_vport_alloc+0x7f/0xf0  net/openvswitch/vport.c:139
>       [<00000000f9a04a7d>] internal_dev_create+0x24/0x1d0  net/openvswitch/vport-internal_dev.c:164
>       [<0000000056ee7c13>] ovs_vport_add+0x81/0x190  net/openvswitch/vport.c:199
>       [<000000005434efc7>] new_vport+0x19/0x80 net/openvswitch/datapath.c:194
>       [<00000000b7b253f1>] ovs_dp_cmd_new+0x22f/0x410  net/openvswitch/datapath.c:1614
>       [<00000000e0988518>] genl_family_rcv_msg+0x2ab/0x5b0  net/netlink/genetlink.c:629
>       [<00000000d0cc9347>] genl_rcv_msg+0x54/0x9c net/netlink/genetlink.c:654
>       [<000000006694b647>] netlink_rcv_skb+0x61/0x170  net/netlink/af_netlink.c:2477
>       [<0000000088381f37>] genl_rcv+0x29/0x40 net/netlink/genetlink.c:665
>       [<00000000dad42a47>] netlink_unicast_kernel  net/netlink/af_netlink.c:1302 [inline]
>       [<00000000dad42a47>] netlink_unicast+0x1ec/0x2d0  net/netlink/af_netlink.c:1328
>       [<0000000067e6b079>] netlink_sendmsg+0x270/0x480  net/netlink/af_netlink.c:1917
>       [<00000000aab08a47>] sock_sendmsg_nosec net/socket.c:637 [inline]
>       [<00000000aab08a47>] sock_sendmsg+0x54/0x70 net/socket.c:657
>       [<000000004cb7c11d>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2311
>       [<00000000c4901c63>] __sys_sendmsg+0x80/0xf0 net/socket.c:2356
>
> BUG: memory leak
> unreferenced object 0xffff8881228ca500 (size 128):
>     comm "syz-executor032", pid 7015, jiffies 4294944622 (age 7.880s)
>     hex dump (first 32 bytes):
>       00 f0 27 18 81 88 ff ff 80 ac 8c 22 81 88 ff ff  ..'........"....
>       40 b7 23 17 81 88 ff ff 00 00 00 00 00 00 00 00  @.#.............
>     backtrace:
>       [<000000000eb78212>] kmemleak_alloc_recursive  include/linux/kmemleak.h:43 [inline]
>       [<000000000eb78212>] slab_post_alloc_hook mm/slab.h:522 [inline]
>       [<000000000eb78212>] slab_alloc mm/slab.c:3319 [inline]
>       [<000000000eb78212>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
>       [<00000000006ea6c6>] kmalloc include/linux/slab.h:552 [inline]
>       [<00000000006ea6c6>] kzalloc include/linux/slab.h:748 [inline]
>       [<00000000006ea6c6>] ovs_vport_alloc+0x37/0xf0  net/openvswitch/vport.c:130
>       [<00000000f9a04a7d>] internal_dev_create+0x24/0x1d0  net/openvswitch/vport-internal_dev.c:164
>       [<0000000056ee7c13>] ovs_vport_add+0x81/0x190  net/openvswitch/vport.c:199
>       [<000000005434efc7>] new_vport+0x19/0x80 net/openvswitch/datapath.c:194
>       [<00000000b7b253f1>] ovs_dp_cmd_new+0x22f/0x410  net/openvswitch/datapath.c:1614
>       [<00000000e0988518>] genl_family_rcv_msg+0x2ab/0x5b0  net/netlink/genetlink.c:629
>       [<00000000d0cc9347>] genl_rcv_msg+0x54/0x9c net/netlink/genetlink.c:654
>       [<000000006694b647>] netlink_rcv_skb+0x61/0x170  net/netlink/af_netlink.c:2477
>       [<0000000088381f37>] genl_rcv+0x29/0x40 net/netlink/genetlink.c:665
>       [<00000000dad42a47>] netlink_unicast_kernel  net/netlink/af_netlink.c:1302 [inline]
>       [<00000000dad42a47>] netlink_unicast+0x1ec/0x2d0  net/netlink/af_netlink.c:1328
>       [<0000000067e6b079>] netlink_sendmsg+0x270/0x480  net/netlink/af_netlink.c:1917
>       [<00000000aab08a47>] sock_sendmsg_nosec net/socket.c:637 [inline]
>       [<00000000aab08a47>] sock_sendmsg+0x54/0x70 net/socket.c:657
>       [<000000004cb7c11d>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2311
>       [<00000000c4901c63>] __sys_sendmsg+0x80/0xf0 net/socket.c:2356
>       [<00000000c10abb2d>] __do_sys_sendmsg net/socket.c:2365 [inline]
>       [<00000000c10abb2d>] __se_sys_sendmsg net/socket.c:2363 [inline]
>       [<00000000c10abb2d>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2363
> =====================================================================
>
> The function in net core, register_netdevice(), may fail with vport's
> destruction callback either invoked or not. After commit 309b66970ee2,
> the duty to destroy vport is offloaded from the driver OTOH, which ends
> up in the memory leak reported.
>
> It is fixed by releasing vport unless device is registered successfully.
> To do that, the callback assignment is defered until device is registered.
>
> Reported-by: syzbot+13210896153522fe1ee5@syzkaller.appspotmail.com
> Fixes: 309b66970ee2 ("net: openvswitch: do not free vport if register_netdevice() is failed.")
> Cc: Taehee Yoo <ap420073@gmail.com>
> Cc: Greg Rose <gvrose8192@gmail.com>
> Cc: Eric Dumazet <eric.dumazet@gmail.com>
> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
> Cc: Ying Xue <ying.xue@windriver.com>
> Cc: Andrey Konovalov <andreyknvl@google.com>
> Signed-off-by: Hillf Danton <hdanton@sina.com>
> Acked-by: Pravin B Shelar <pshelar@ovn.org>
> [sbrivio: this was sent to dev@openvswitch.org and never made its way
>   to netdev -- resending original patch]
> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
> ---
> This patch was sent to dev@openvswitch.org and appeared on netdev
> only as Pravin replied to it, giving his Acked-by. I contacted the
> original author one month ago requesting to resend this to netdev,
> but didn't get an answer, so I'm now resending the original patch.
>
>   net/openvswitch/vport-internal_dev.c | 11 ++++-------
>   1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/net/openvswitch/vport-internal_dev.c b/net/openvswitch/vport-internal_dev.c
> index 21c90d3a7ebf..58a7b8312c28 100644
> --- a/net/openvswitch/vport-internal_dev.c
> +++ b/net/openvswitch/vport-internal_dev.c
> @@ -137,7 +137,7 @@ static void do_setup(struct net_device *netdev)
>   	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH |
>   			      IFF_NO_QUEUE;
>   	netdev->needs_free_netdev = true;
> -	netdev->priv_destructor = internal_dev_destructor;
> +	netdev->priv_destructor = NULL;
>   	netdev->ethtool_ops = &internal_dev_ethtool_ops;
>   	netdev->rtnl_link_ops = &internal_dev_link_ops;
>   
> @@ -159,7 +159,6 @@ static struct vport *internal_dev_create(const struct vport_parms *parms)
>   	struct internal_dev *internal_dev;
>   	struct net_device *dev;
>   	int err;
> -	bool free_vport = true;
>   
>   	vport = ovs_vport_alloc(0, &ovs_internal_vport_ops, parms);
>   	if (IS_ERR(vport)) {
> @@ -190,10 +189,9 @@ static struct vport *internal_dev_create(const struct vport_parms *parms)
>   
>   	rtnl_lock();
>   	err = register_netdevice(vport->dev);
> -	if (err) {
> -		free_vport = false;
> +	if (err)
>   		goto error_unlock;
> -	}
> +	vport->dev->priv_destructor = internal_dev_destructor;
>   
>   	dev_set_promiscuity(vport->dev, 1);
>   	rtnl_unlock();
> @@ -207,8 +205,7 @@ static struct vport *internal_dev_create(const struct vport_parms *parms)
>   error_free_netdev:
>   	free_netdev(dev);
>   error_free_vport:
> -	if (free_vport)
> -		ovs_vport_free(vport);
> +	ovs_vport_free(vport);
>   error:
>   	return ERR_PTR(err);
>   }

Thanks Stefano and Hillf.  LGTM

Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Jakub Kicinski Oct. 22, 2019, 9:53 p.m. UTC | #2
On Mon, 21 Oct 2019 12:01:57 +0200, Stefano Brivio wrote:
> From: Hillf Danton <hdanton@sina.com>
> 
> syzbot found the following crash on:
 
> The function in net core, register_netdevice(), may fail with vport's
> destruction callback either invoked or not. After commit 309b66970ee2,

I've added the correct commit quote here, please heed checkpatch'es
warnings.

> the duty to destroy vport is offloaded from the driver OTOH, which ends
> up in the memory leak reported.
> 
> It is fixed by releasing vport unless device is registered successfully.
> To do that, the callback assignment is defered until device is registered.
> 
> Reported-by: syzbot+13210896153522fe1ee5@syzkaller.appspotmail.com
> Fixes: 309b66970ee2 ("net: openvswitch: do not free vport if register_netdevice() is failed.")
> Cc: Taehee Yoo <ap420073@gmail.com>
> Cc: Greg Rose <gvrose8192@gmail.com>
> Cc: Eric Dumazet <eric.dumazet@gmail.com>
> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
> Cc: Ying Xue <ying.xue@windriver.com>
> Cc: Andrey Konovalov <andreyknvl@google.com>
> Signed-off-by: Hillf Danton <hdanton@sina.com>
> Acked-by: Pravin B Shelar <pshelar@ovn.org>
> [sbrivio: this was sent to dev@openvswitch.org and never made its way
>  to netdev -- resending original patch]
> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
> ---
> This patch was sent to dev@openvswitch.org and appeared on netdev
> only as Pravin replied to it, giving his Acked-by. I contacted the
> original author one month ago requesting to resend this to netdev,
> but didn't get an answer, so I'm now resending the original patch.

Applied and queued for 4.14+, thanks!
Stefano Brivio Oct. 23, 2019, 12:20 a.m. UTC | #3
Hi Jakub,

On Tue, 22 Oct 2019 14:53:16 -0700
Jakub Kicinski <jakub.kicinski@netronome.com> wrote:

> On Mon, 21 Oct 2019 12:01:57 +0200, Stefano Brivio wrote:
> > From: Hillf Danton <hdanton@sina.com>
> > 
> > syzbot found the following crash on:  
>  
> > The function in net core, register_netdevice(), may fail with vport's
> > destruction callback either invoked or not. After commit 309b66970ee2,  
> 
> I've added the correct commit quote here, please heed checkpatch'es
> warnings.

I disregarded this warning as it looks redundant to me, given that the
full commit quote is already given in the Fixes: tag below.

In this specific case, I guess it doesn't really make a difference, but
sometimes one needs to mention the same commit multiple times in the
actual message, and while checkpatch would complain about every single
instance, I think that providing the full quote for each of them isn't
very useful and hinders readability.

> > Reported-by: syzbot+13210896153522fe1ee5@syzkaller.appspotmail.com
> > Fixes: 309b66970ee2 ("net: openvswitch: do not free vport if register_netdevice() is failed.")
> > Cc: Taehee Yoo <ap420073@gmail.com>
> > Cc: Greg Rose <gvrose8192@gmail.com>
> > Cc: Eric Dumazet <eric.dumazet@gmail.com>
> > Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
> > Cc: Ying Xue <ying.xue@windriver.com>
> > Cc: Andrey Konovalov <andreyknvl@google.com>
> > Signed-off-by: Hillf Danton <hdanton@sina.com>
> > Acked-by: Pravin B Shelar <pshelar@ovn.org>
> > [sbrivio: this was sent to dev@openvswitch.org and never made its way
> >  to netdev -- resending original patch]
> > Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
> > ---
> > This patch was sent to dev@openvswitch.org and appeared on netdev
> > only as Pravin replied to it, giving his Acked-by. I contacted the
> > original author one month ago requesting to resend this to netdev,
> > but didn't get an answer, so I'm now resending the original patch.  
> 
> Applied and queued for 4.14+, thanks!

Thank you!

Patch
diff mbox series

diff --git a/net/openvswitch/vport-internal_dev.c b/net/openvswitch/vport-internal_dev.c
index 21c90d3a7ebf..58a7b8312c28 100644
--- a/net/openvswitch/vport-internal_dev.c
+++ b/net/openvswitch/vport-internal_dev.c
@@ -137,7 +137,7 @@  static void do_setup(struct net_device *netdev)
 	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH |
 			      IFF_NO_QUEUE;
 	netdev->needs_free_netdev = true;
-	netdev->priv_destructor = internal_dev_destructor;
+	netdev->priv_destructor = NULL;
 	netdev->ethtool_ops = &internal_dev_ethtool_ops;
 	netdev->rtnl_link_ops = &internal_dev_link_ops;
 
@@ -159,7 +159,6 @@  static struct vport *internal_dev_create(const struct vport_parms *parms)
 	struct internal_dev *internal_dev;
 	struct net_device *dev;
 	int err;
-	bool free_vport = true;
 
 	vport = ovs_vport_alloc(0, &ovs_internal_vport_ops, parms);
 	if (IS_ERR(vport)) {
@@ -190,10 +189,9 @@  static struct vport *internal_dev_create(const struct vport_parms *parms)
 
 	rtnl_lock();
 	err = register_netdevice(vport->dev);
-	if (err) {
-		free_vport = false;
+	if (err)
 		goto error_unlock;
-	}
+	vport->dev->priv_destructor = internal_dev_destructor;
 
 	dev_set_promiscuity(vport->dev, 1);
 	rtnl_unlock();
@@ -207,8 +205,7 @@  static struct vport *internal_dev_create(const struct vport_parms *parms)
 error_free_netdev:
 	free_netdev(dev);
 error_free_vport:
-	if (free_vport)
-		ovs_vport_free(vport);
+	ovs_vport_free(vport);
 error:
 	return ERR_PTR(err);
 }