1. 20 Mar, 2019 2 commits
    • Xin Long's avatar
      ipv6: make ip6_create_rt_rcu return ip6_null_entry instead of NULL · 1c87e79a
      Xin Long authored
      Jianlin reported a crash:
      
        [  381.484332] BUG: unable to handle kernel NULL pointer dereference at 0000000000000068
        [  381.619802] RIP: 0010:fib6_rule_lookup+0xa3/0x160
        [  382.009615] Call Trace:
        [  382.020762]  <IRQ>
        [  382.030174]  ip6_route_redirect.isra.52+0xc9/0xf0
        [  382.050984]  ip6_redirect+0xb6/0xf0
        [  382.066731]  icmpv6_notify+0xca/0x190
        [  382.083185]  ndisc_redirect_rcv+0x10f/0x160
        [  382.102569]  ndisc_rcv+0xfb/0x100
        [  382.117725]  icmpv6_rcv+0x3f2/0x520
        [  382.133637]  ip6_input_finish+0xbf/0x460
        [  382.151634]  ip6_input+0x3b/0xb0
        [  382.166097]  ipv6_rcv+0x378/0x4e0
      
      It was caused by the lookup function __ip6_route_redirect() returns NULL in
      fib6_rule_lookup() when ip6_create_rt_rcu() returns NULL.
      
      So we fix it by simply making ip6_create_rt_rcu() return ip6_null_entry
      instead of NULL.
      
      v1->v2:
        - move down 'fallback:' to make it more readable.
      
      Fixes: e873e4b9 ("ipv6: use fib6_info_hold_safe() when necessary")
      Reported-by: default avatarJianlin Shi <jishi@redhat.com>
      Suggested-by: default avatarPaolo Abeni <pabeni@redhat.com>
      Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
      Reviewed-by: default avatarDavid Ahern <dsahern@gmail.com>
      Acked-by: default avatarWei Wang <weiwan@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      1c87e79a
    • Christoph Paasch's avatar
      net/packet: Set __GFP_NOWARN upon allocation in alloc_pg_vec · 398f0132
      Christoph Paasch authored
      Since commit fc62814d ("net/packet: fix 4gb buffer limit due to overflow check")
      one can now allocate packet ring buffers >= UINT_MAX. However, syzkaller
      found that that triggers a warning:
      
      [   21.100000] WARNING: CPU: 2 PID: 2075 at mm/page_alloc.c:4584 __alloc_pages_nod0
      [   21.101490] Modules linked in:
      [   21.101921] CPU: 2 PID: 2075 Comm: syz-executor.0 Not tainted 5.0.0 #146
      [   21.102784] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.5.1 01/01/2011
      [   21.103887] RIP: 0010:__alloc_pages_nodemask+0x2a0/0x630
      [   21.104640] Code: fe ff ff 65 48 8b 04 25 c0 de 01 00 48 05 90 0f 00 00 41 bd 01 00 00 00 48 89 44 24 48 e9 9c fe 3
      [   21.107121] RSP: 0018:ffff88805e1cf920 EFLAGS: 00010246
      [   21.107819] RAX: 0000000000000000 RBX: ffffffff85a488a0 RCX: 0000000000000000
      [   21.108753] RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 0000000000000000
      [   21.109699] RBP: 1ffff1100bc39f28 R08: ffffed100bcefb67 R09: ffffed100bcefb67
      [   21.110646] R10: 0000000000000001 R11: ffffed100bcefb66 R12: 000000000000000d
      [   21.111623] R13: 0000000000000000 R14: ffff88805e77d888 R15: 000000000000000d
      [   21.112552] FS:  00007f7c7de05700(0000) GS:ffff88806d100000(0000) knlGS:0000000000000000
      [   21.113612] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [   21.114405] CR2: 000000000065c000 CR3: 000000005e58e006 CR4: 00000000001606e0
      [   21.115367] Call Trace:
      [   21.115705]  ? __alloc_pages_slowpath+0x21c0/0x21c0
      [   21.116362]  alloc_pages_current+0xac/0x1e0
      [   21.116923]  kmalloc_order+0x18/0x70
      [   21.117393]  kmalloc_order_trace+0x18/0x110
      [   21.117949]  packet_set_ring+0x9d5/0x1770
      [   21.118524]  ? packet_rcv_spkt+0x440/0x440
      [   21.119094]  ? lock_downgrade+0x620/0x620
      [   21.119646]  ? __might_fault+0x177/0x1b0
      [   21.120177]  packet_setsockopt+0x981/0x2940
      [   21.120753]  ? __fget+0x2fb/0x4b0
      [   21.121209]  ? packet_release+0xab0/0xab0
      [   21.121740]  ? sock_has_perm+0x1cd/0x260
      [   21.122297]  ? selinux_secmark_relabel_packet+0xd0/0xd0
      [   21.123013]  ? __fget+0x324/0x4b0
      [   21.123451]  ? selinux_netlbl_socket_setsockopt+0x101/0x320
      [   21.124186]  ? selinux_netlbl_sock_rcv_skb+0x3a0/0x3a0
      [   21.124908]  ? __lock_acquire+0x529/0x3200
      [   21.125453]  ? selinux_socket_setsockopt+0x5d/0x70
      [   21.126075]  ? __sys_setsockopt+0x131/0x210
      [   21.126533]  ? packet_release+0xab0/0xab0
      [   21.127004]  __sys_setsockopt+0x131/0x210
      [   21.127449]  ? kernel_accept+0x2f0/0x2f0
      [   21.127911]  ? ret_from_fork+0x8/0x50
      [   21.128313]  ? do_raw_spin_lock+0x11b/0x280
      [   21.128800]  __x64_sys_setsockopt+0xba/0x150
      [   21.129271]  ? lockdep_hardirqs_on+0x37f/0x560
      [   21.129769]  do_syscall_64+0x9f/0x450
      [   21.130182]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
      
      We should allocate with __GFP_NOWARN to handle this.
      
      Cc: Kal Conley <kal.conley@dectris.com>
      Cc: Andrey Konovalov <andreyknvl@google.com>
      Fixes: fc62814d ("net/packet: fix 4gb buffer limit due to overflow check")
      Signed-off-by: default avatarChristoph Paasch <cpaasch@apple.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      398f0132
  2. 19 Mar, 2019 38 commits