1. Aug 02, 2023
  2. Aug 01, 2023
  3. Jul 31, 2023
    • Duoming Zhou's avatar
      net: usb: lan78xx: reorder cleanup operations to avoid UAF bugs · 1e7417c1
      Duoming Zhou authored
      The timer dev->stat_monitor can schedule the delayed work dev->wq and
      the delayed work dev->wq can also arm the dev->stat_monitor timer.
      
      When the device is detaching, the net_device will be deallocated. but
      the net_device private data could still be dereferenced in delayed work
      or timer handler. As a result, the UAF bugs will happen.
      
      One racy situation is shown below:
      
            (Thread 1)                 |      (Thread 2)
      lan78xx_stat_monitor()           |
       ...                             |  lan78xx_disconnect()
       lan78xx_defer_kevent()          |    ...
        ...                            |    cancel_delayed_work_sync(&dev->wq);
        schedule_delayed_work()        |    ...
        (wait some time)               |    free_netdev(net); //free net_device
        lan78xx_delayedwork()          |
        //use net_device private data  |
        dev-> //use                    |
      
      Although we use cancel_delayed_work_sync() to cancel the delayed work
      in lan78xx_disconnect(), it could still be scheduled in timer handler
      lan78xx_stat_monitor().
      
      Another racy situation is shown below:
      
            (Thread 1)                |      (Thread 2)
      lan78xx_delayedwork             |
       mod_timer()                    |  lan78xx_disconnect()
                                      |   cancel_delayed_work_sync()
       (wait some time)               |   if (timer_pending(&dev->stat_monitor))
                   	                |       del_timer_sync(&dev->stat_monitor);
       lan78xx_stat_monitor()         |   ...
        lan78xx_defer_kevent()        |   free_netdev(net); //free
         //use net_device private data|
         dev-> //use                  |
      
      Although we use del_timer_sync() to delete the timer, the function
      timer_pending() returns 0 when the timer is activated. As a result,
      the del_timer_sync() will not be executed and the timer could be
      re-armed.
      
      In order to mitigate this bug, We use timer_shutdown_sync() to shutdown
      the timer and then use cancel_delayed_work_sync() to cancel the delayed
      work. As a result, the net_device could be deallocated safely.
      
      What's more, the dev->flags is set to EVENT_DEV_DISCONNECT in
      lan78xx_disconnect(). But it could still be set to EVENT_STAT_UPDATE
      in lan78xx_stat_monitor(). So this patch put the set_bit() behind
      timer_shutdown_sync().
      
      Fixes: 77dfff5b
      
       ("lan78xx: Fix race condition in disconnect handling")
      Signed-off-by: default avatarDuoming Zhou <duoming@zju.edu.cn>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      1e7417c1
    • Rafał Miłecki's avatar
      dt-bindings: net: mediatek,net: fixup MAC binding · 8469c7f5
      Rafał Miłecki authored
      
      
      1. Use unevaluatedProperties
      It's needed to allow ethernet-controller.yaml properties work correctly.
      
      2. Drop unneeded phy-handle/phy-mode
      
      3. Don't require phy-handle
      Some SoCs may use fixed link.
      
      For in-kernel MT7621 DTS files this fixes following errors:
      arch/mips/boot/dts/ralink/mt7621-tplink-hc220-g5-v1.dtb: ethernet@1e100000: mac@0: 'fixed-link' does not match any of the regexes: 'pinctrl-[0-9]+'
              From schema: Documentation/devicetree/bindings/net/mediatek,net.yaml
      arch/mips/boot/dts/ralink/mt7621-tplink-hc220-g5-v1.dtb: ethernet@1e100000: mac@0: 'phy-handle' is a required property
              From schema: Documentation/devicetree/bindings/net/mediatek,net.yaml
      arch/mips/boot/dts/ralink/mt7621-tplink-hc220-g5-v1.dtb: ethernet@1e100000: mac@1: 'fixed-link' does not match any of the regexes: 'pinctrl-[0-9]+'
              From schema: Documentation/devicetree/bindings/net/mediatek,net.yaml
      arch/mips/boot/dts/ralink/mt7621-tplink-hc220-g5-v1.dtb: ethernet@1e100000: mac@1: 'phy-handle' is a required property
              From schema: Documentation/devicetree/bindings/net/mediatek,net.yaml
      
      Signed-off-by: default avatarRafał Miłecki <rafal@milecki.pl>
      Reviewed-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8469c7f5
    • Kuniyuki Iwashima's avatar
      net/sched: taprio: Limit TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME to INT_MAX. · e7397184
      Kuniyuki Iwashima authored
      syzkaller found zero division error [0] in div_s64_rem() called from
      get_cycle_time_elapsed(), where sched->cycle_time is the divisor.
      
      We have tests in parse_taprio_schedule() so that cycle_time will never
      be 0, and actually cycle_time is not 0 in get_cycle_time_elapsed().
      
      The problem is that the types of divisor are different; cycle_time is
      s64, but the argument of div_s64_rem() is s32.
      
      syzkaller fed this input and 0x100000000 is cast to s32 to be 0.
      
        @TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME={0xc, 0x8, 0x100000000}
      
      We use s64 for cycle_time to cast it to ktime_t, so let's keep it and
      set max for cycle_time.
      
      While at it, we prevent overflow in setup_txtime() and add another
      test in parse_taprio_schedule() to check if cycle_time overflows.
      
      Also, we add a new tdc test case for this issue.
      
      [0]:
      divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
      CPU: 1 PID: 103 Comm: kworker/1:3 Not tainted 6.5.0-rc1-00330-g60cc1f7d #3
      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
      Workqueue: ipv6_addrconf addrconf_dad_work
      RIP: 0010:div_s64_rem include/linux/math64.h:42 [inline]
      RIP: 0010:get_cycle_time_elapsed net/sched/sch_taprio.c:223 [inline]
      RIP: 0010:find_entry_to_transmit+0x252/0x7e0 net/sched/sch_taprio.c:344
      Code: 3c 02 00 0f 85 5e 05 00 00 48 8b 4c 24 08 4d 8b bd 40 01 00 00 48 8b 7c 24 48 48 89 c8 4c 29 f8 48 63 f7 48 99 48 89 74 24 70 <48> f7 fe 48 29 d1 48 8d 04 0f 49 89 cc 48 89 44 24 20 49 8d 85 10
      RSP: 0018:ffffc90000acf260 EFLAGS: 00010206
      RAX: 177450e0347560cf RBX: 0000000000000000 RCX: 177450e0347560cf
      RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000100000000
      RBP: 0000000000000056 R08: 0000000000000000 R09: ffffed10020a0934
      R10: ffff8880105049a7 R11: ffff88806cf3a520 R12: ffff888010504800
      R13: ffff88800c00d800 R14: ffff8880105049a0 R15: 0000000000000000
      FS:  0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 00007f0edf84f0e8 CR3: 000000000d73c002 CR4: 0000000000770ee0
      PKRU: 55555554
      Call Trace:
       <TASK>
       get_packet_txtime net/sched/sch_taprio.c:508 [inline]
       taprio_enqueue_one+0x900/0xff0 net/sched/sch_taprio.c:577
       taprio_enqueue+0x378/0xae0 net/sched/sch_taprio.c:658
       dev_qdisc_enqueue+0x46/0x170 net/core/dev.c:3732
       __dev_xmit_skb net/core/dev.c:3821 [inline]
       __dev_queue_xmit+0x1b2f/0x3000 net/core/dev.c:4169
       dev_queue_xmit include/linux/netdevice.h:3088 [inline]
       neigh_resolve_output net/core/neighbour.c:1552 [inline]
       neigh_resolve_output+0x4a7/0x780 net/core/neighbour.c:1532
       neigh_output include/net/neighbour.h:544 [inline]
       ip6_finish_output2+0x924/0x17d0 net/ipv6/ip6_output.c:135
       __ip6_finish_output+0x620/0xaa0 net/ipv6/ip6_output.c:196
       ip6_finish_output net/ipv6/ip6_output.c:207 [inline]
       NF_HOOK_COND include/linux/netfilter.h:292 [inline]
       ip6_output+0x206/0x410 net/ipv6/ip6_output.c:228
       dst_output include/net/dst.h:458 [inline]
       NF_HOOK.constprop.0+0xea/0x260 include/linux/netfilter.h:303
       ndisc_send_skb+0x872/0xe80 net/ipv6/ndisc.c:508
       ndisc_send_ns+0xb5/0x130 net/ipv6/ndisc.c:666
       addrconf_dad_work+0xc14/0x13f0 net/ipv6/addrconf.c:4175
       process_one_work+0x92c/0x13a0 kernel/workqueue.c:2597
       worker_thread+0x60f/0x1240 kernel/workqueue.c:2748
       kthread+0x2fe/0x3f0 kernel/kthread.c:389
       ret_from_fork+0x2c/0x50 arch/x86/entry/entry_64.S:308
       </TASK>
      Modules linked in:
      
      Fixes: 4cfd5779
      
       ("taprio: Add support for txtime-assist mode")
      Reported-by: default avatarsyzkaller <syzkaller@googlegroups.com>
      Signed-off-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
      Co-developed-by: default avatarEric Dumazet <edumazet@google.com>
      Co-developed-by: default avatarPedro Tammela <pctammela@mojatatu.com>
      Acked-by: default avatarVinicius Costa Gomes <vinicius.gomes@intel.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e7397184
  4. Jul 30, 2023
  5. Jul 29, 2023