1. 08 Nov, 2019 3 commits
    • David Ahern's avatar
      ipv4: Fix table id reference in fib_sync_down_addr · e0a31262
      David Ahern authored
      Hendrik reported routes in the main table using source address are not
      removed when the address is removed. The problem is that fib_sync_down_addr
      does not account for devices in the default VRF which are associated
      with the main table. Fix by updating the table id reference.
      
      Fixes: 5a56a0b3 ("net: Don't delete routes in different VRFs")
      Reported-by: default avatarHendrik Donner <hd@os-cillation.de>
      Signed-off-by: default avatarDavid Ahern <dsahern@kernel.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e0a31262
    • Eric Dumazet's avatar
      ipv6: fixes rt6_probe() and fib6_nh->last_probe init · 1bef4c22
      Eric Dumazet authored
      While looking at a syzbot KCSAN report [1], I found multiple
      issues in this code :
      
      1) fib6_nh->last_probe has an initial value of 0.
      
         While probably okay on 64bit kernels, this causes an issue
         on 32bit kernels since the time_after(jiffies, 0 + interval)
         might be false ~24 days after boot (for HZ=1000)
      
      2) The data-race found by KCSAN
         I could use READ_ONCE() and WRITE_ONCE(), but we also can
         take the opportunity of not piling-up too many rt6_probe_deferred()
         works by using instead cmpxchg() so that only one cpu wins the race.
      
      [1]
      BUG: KCSAN: data-race in find_match / find_match
      
      write to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 1:
       rt6_probe net/ipv6/route.c:663 [inline]
       find_match net/ipv6/route.c:757 [inline]
       find_match+0x5bd/0x790 net/ipv6/route.c:733
       __find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831
       find_rr_leaf net/ipv6/route.c:852 [inline]
       rt6_select net/ipv6/route.c:896 [inline]
       fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164
       ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200
       ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452
       fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117
       ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484
       ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497
       ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049
       ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150
       inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106
       inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121
       __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
       tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline]
       tcp_xmit_probe_skb+0x19b/0x1d0 net/ipv4/tcp_output.c:3735
      
      read to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 0:
       rt6_probe net/ipv6/route.c:657 [inline]
       find_match net/ipv6/route.c:757 [inline]
       find_match+0x521/0x790 net/ipv6/route.c:733
       __find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831
       find_rr_leaf net/ipv6/route.c:852 [inline]
       rt6_select net/ipv6/route.c:896 [inline]
       fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164
       ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200
       ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452
       fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117
       ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484
       ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497
       ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049
       ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150
       inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106
       inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121
       __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
      
      Reported by Kernel Concurrency Sanitizer on:
      CPU: 0 PID: 18894 Comm: udevd Not tainted 5.4.0-rc3+ #0
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      
      Fixes: cc3a86c8 ("ipv6: Change rt6_probe to take a fib6_nh")
      Fixes: f547fac6 ("ipv6: rate-limit probes for neighbourless routes")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
      Reviewed-by: default avatarDavid Ahern <dsahern@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      1bef4c22
    • Salil Mehta's avatar
      net: hns: Fix the stray netpoll locks causing deadlock in NAPI path · bf5a6b4c
      Salil Mehta authored
      This patch fixes the problem of the spin locks, originally
      meant for the netpoll path of hns driver, causing deadlock in
      the normal NAPI poll path. The issue happened due to the presence
      of the stray leftover spin lock code related to the netpoll,
      whose support was earlier removed from the HNS[1], got activated
      due to enabling of NET_POLL_CONTROLLER switch.
      
      Earlier background:
      The netpoll handling code originally had this bug(as identified
      by Marc Zyngier[2]) of wrong spin lock API being used which did
      not disable the interrupts and hence could cause locking issues.
      i.e. if the lock were first acquired in context to thread like
      'ip' util and this lock if ever got later acquired again in
      context to the interrupt context like TX/RX (Interrupts could
      always pre-empt the lock holding task and acquire the lock again)
      and hence could cause deadlock.
      
      Proposed Solution:
      1. If the netpoll was enabled in the HNS driver, which is not
         right now, we could have simply used spin_[un]lock_irqsave()
      2. But as netpoll is disabled, therefore, it is best to get rid
         of the existing locks and stray code for now. This should
         solve the problem reported by Marc.
      
      [1] https://git.kernel.org/torvalds/c/4bd2c03be7
      [2] https://patchwork.ozlabs.org/patch/1189139/
      
      Fixes: 4bd2c03b ("net: hns: remove ndo_poll_controller")
      Cc: lipeng <lipeng321@huawei.com>
      Cc: Yisen Zhuang <yisen.zhuang@huawei.com>
      Cc: Eric Dumazet <edumazet@google.com>
      Cc: David S. Miller <davem@davemloft.net>
      Reported-by: default avatarMarc Zyngier <maz@kernel.org>
      Acked-by: default avatarMarc Zyngier <maz@kernel.org>
      Tested-by: default avatarMarc Zyngier <maz@kernel.org>
      Signed-off-by: default avatarSalil Mehta <salil.mehta@huawei.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bf5a6b4c
  2. 07 Nov, 2019 25 commits
  3. 06 Nov, 2019 12 commits