1. 09 Jan, 2019 4 commits
    • Lorenzo Bianconi's avatar
      gro_cell: add napi_disable in gro_cells_destroy · 79d222d8
      Lorenzo Bianconi authored
      [ Upstream commit 8e1da73a ]
      
      Add napi_disable routine in gro_cells_destroy since starting from
      commit c42858ea ("gro_cells: remove spinlock protecting receive
      queues") gro_cell_poll and gro_cells_destroy can run concurrently on
      napi_skbs list producing a kernel Oops if the tunnel interface is
      removed while gro_cell_poll is running. The following Oops has been
      triggered removing a vxlan device while the interface is receiving
      traffic
      
      [ 5628.948853] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
      [ 5628.949981] PGD 0 P4D 0
      [ 5628.950308] Oops: 0002 [#1] SMP PTI
      [ 5628.950748] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 4.20.0-rc6+ #41
      [ 5628.952940] RIP: 0010:gro_cell_poll+0x49/0x80
      [ 5628.955615] RSP: 0018:ffffc9000004fdd8 EFLAGS: 00010202
      [ 5628.956250] RAX: 0000000000000000 RBX: ffffe8ffffc08150 RCX: 0000000000000000
      [ 5628.957102] RDX: 0000000000000000 RSI: ffff88802356bf00 RDI: ffffe8ffffc08150
      [ 5628.957940] RBP: 0000000000000026 R08: 0000000000000000 R09: 0000000000000000
      [ 5628.958803] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000040
      [ 5628.959661] R13: ffffe8ffffc08100 R14: 0000000000000000 R15: 0000000000000040
      [ 5628.960682] FS:  0000000000000000(0000) GS:ffff88803ea00000(0000) knlGS:0000000000000000
      [ 5628.961616] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [ 5628.962359] CR2: 0000000000000008 CR3: 000000000221c000 CR4: 00000000000006b0
      [ 5628.963188] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      [ 5628.964034] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      [ 5628.964871] Call Trace:
      [ 5628.965179]  net_rx_action+0xf0/0x380
      [ 5628.965637]  __do_softirq+0xc7/0x431
      [ 5628.966510]  run_ksoftirqd+0x24/0x30
      [ 5628.966957]  smpboot_thread_fn+0xc5/0x160
      [ 5628.967436]  kthread+0x113/0x130
      [ 5628.968283]  ret_from_fork+0x3a/0x50
      [ 5628.968721] Modules linked in:
      [ 5628.969099] CR2: 0000000000000008
      [ 5628.969510] ---[ end trace 9d9dedc7181661fe ]---
      [ 5628.970073] RIP: 0010:gro_cell_poll+0x49/0x80
      [ 5628.972965] RSP: 0018:ffffc9000004fdd8 EFLAGS: 00010202
      [ 5628.973611] RAX: 0000000000000000 RBX: ffffe8ffffc08150 RCX: 0000000000000000
      [ 5628.974504] RDX: 0000000000000000 RSI: ffff88802356bf00 RDI: ffffe8ffffc08150
      [ 5628.975462] RBP: 0000000000000026 R08: 0000000000000000 R09: 0000000000000000
      [ 5628.976413] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000040
      [ 5628.977375] R13: ffffe8ffffc08100 R14: 0000000000000000 R15: 0000000000000040
      [ 5628.978296] FS:  0000000000000000(0000) GS:ffff88803ea00000(0000) knlGS:0000000000000000
      [ 5628.979327] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [ 5628.980044] CR2: 0000000000000008 CR3: 000000000221c000 CR4: 00000000000006b0
      [ 5628.980929] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      [ 5628.981736] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      [ 5628.982409] Kernel panic - not syncing: Fatal exception in interrupt
      [ 5628.983307] Kernel Offset: disabled
      
      Fixes: c42858ea ("gro_cells: remove spinlock protecting receive queues")
      Signed-off-by: default avatarLorenzo Bianconi <lorenzo.bianconi@redhat.com>
      Acked-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      79d222d8
    • Cong Wang's avatar
      ax25: fix a use-after-free in ax25_fillin_cb() · 26a5adc8
      Cong Wang authored
      [ Upstream commit c4335704 ]
      
      There are multiple issues here:
      
      1. After freeing dev->ax25_ptr, we need to set it to NULL otherwise
         we may use a dangling pointer.
      
      2. There is a race between ax25_setsockopt() and device notifier as
         reported by syzbot. Close it by holding RTNL lock.
      
      3. We need to test if dev->ax25_ptr is NULL before using it.
      
      Reported-and-tested-by: syzbot+ae6bb869cbed29b29040@syzkaller.appspotmail.com
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      26a5adc8
    • Gustavo A. R. Silva's avatar
      ip6mr: Fix potential Spectre v1 vulnerability · 18e260fd
      Gustavo A. R. Silva authored
      [ Upstream commit 69d2c867 ]
      
      vr.mifi is indirectly controlled by user-space, hence leading to
      a potential exploitation of the Spectre variant 1 vulnerability.
      
      This issue was detected with the help of Smatch:
      
      net/ipv6/ip6mr.c:1845 ip6mr_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)
      net/ipv6/ip6mr.c:1919 ip6mr_compat_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)
      
      Fix this by sanitizing vr.mifi before using it to index mrt->vif_table'
      
      Notice that given that speculation windows are large, the policy is
      to kill the speculation on the first load and not worry if it can be
      completed with a dependent load/store [1].
      
      [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      18e260fd
    • Gustavo A. R. Silva's avatar
      ipv4: Fix potential Spectre v1 vulnerability · 26a697a9
      Gustavo A. R. Silva authored
      [ Upstream commit 5648451e ]
      
      vr.vifi is indirectly controlled by user-space, hence leading to
      a potential exploitation of the Spectre variant 1 vulnerability.
      
      This issue was detected with the help of Smatch:
      
      net/ipv4/ipmr.c:1616 ipmr_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)
      net/ipv4/ipmr.c:1690 ipmr_compat_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)
      
      Fix this by sanitizing vr.vifi before using it to index mrt->vif_table'
      
      Notice that given that speculation windows are large, the policy is
      to kill the speculation on the first load and not worry if it can be
      completed with a dependent load/store [1].
      
      [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      26a697a9
  2. 29 Dec, 2018 36 commits