• Jason Gunthorpe's avatar
    RDMA: Add missed netdev_put() for the netdevice_tracker · e42f9c2e
    Jason Gunthorpe authored
    The netdev core will detect if any untracked puts are done on tracked
    pointers and throw refcount warnings:
    
      refcount_t: decrement hit 0; leaking memory.
      WARNING: CPU: 1 PID: 33 at lib/refcount.c:31 refcount_warn_saturate+0x1d7/0x1f0 lib/refcount.c:31
      Modules linked in:
      CPU: 1 PID: 33 Comm: kworker/u4:2 Not tainted 6.1.0-rc8-next-20221207-syzkaller #0
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
      Workqueue: ib-unreg-wq ib_unregister_work
      RIP: 0010:refcount_warn_saturate+0x1d7/0x1f0 lib/refcount.c:31
      Code: 05 5a 60 51 0a 01 e8 35 0a b5 05 0f 0b e9 d3 fe ff ff e8 6c 9b 75 fd 48 c7 c7 c0 6d a6 8a c6 05 37 60 51 0a 01 e8 16 0a b5 05 <0f> 0b e9 b4 fe
      +ff ff 48 89 ef e8 5a b5 c3 fd e9 5c fe ff ff 0f 1f
      RSP: 0018:ffffc90000aa7b30 EFLAGS: 00010082
      RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
      RDX: ffff8880172f9d40 RSI: ffffffff8166b1dc RDI: fffff52000154f58
      RBP: ffff88807906c600 R08: 0000000000000005 R09: 0000000000000000
      R10: 0000000080000001 R11: 0000000000000000 R12: 1ffff92000154f6b
      R13: 0000000000000000 R14: ffff88807906c600 R15: ffff888046894000
      FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 00007ffe350a8ff8 CR3: 000000007a9e7000 CR4: 00000000003526e0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      Call Trace:
       <TASK>
       __refcount_dec include/linux/refcount.h:344 [inline]
       refcount_dec include/linux/refcount.h:359 [inline]
       ref_tracker_free+0x539/0x6b0 lib/ref_tracker.c:118
       netdev_tracker_free include/linux/netdevice.h:4039 [inline]
       netdev_put include/linux/netdevice.h:4056 [inline]
       dev_put include/linux/netdevice.h:4082 [inline]
       free_netdevs+0x1f8/0x470 drivers/infiniband/core/device.c:2204
       __ib_unregister_device+0xa0/0x1a0 drivers/infiniband/core/device.c:1478
       ib_unregister_work+0x19/0x30 drivers/infiniband/core/device.c:1586
       process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
       worker_thread+0x669/0x1090 kernel/workqueue.c:2436
       kthread+0x2e8/0x3a0 kernel/kthread.c:376
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
    
    So change the missed dev_put for pdata->netdev to also follow the tracker.
    
    Fixes: 09f530f0 ("RDMA: Add netdevice_tracker to ib_device_set_netdev()")
    Reported-by: syzbot+3fd8326d9a0812d19218@syzkaller.appspotmail.com
    Reported-by: syzbot+a1ed8ffe3121380cd5dd@syzkaller.appspotmail.com
    Reported-by: syzbot+8d0a099c8a6d1e4e601c@syzkaller.appspotmail.com
    Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
    Link: https://lore.kernel.org/r/0-v1-e99919867b8d+1e2-netdev_tracker2_jgg@nvidia.comSigned-off-by: default avatarLeon Romanovsky <leon@kernel.org>
    e42f9c2e
device.c 76.8 KB