| From foo@baz Thu 06 Feb 2020 06:56:59 AM GMT |
| From: Eric Dumazet <edumazet@google.com> |
| Date: Mon, 3 Feb 2020 10:15:07 -0800 |
| Subject: net: hsr: fix possible NULL deref in hsr_handle_frame() |
| |
| From: Eric Dumazet <edumazet@google.com> |
| |
| [ Upstream commit 2b5b8251bc9fe2f9118411f037862ee17cf81e97 ] |
| |
| hsr_port_get_rcu() can return NULL, so we need to be careful. |
| |
| general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN |
| KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] |
| CPU: 1 PID: 10249 Comm: syz-executor.5 Not tainted 5.5.0-syzkaller #0 |
| Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 |
| RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline] |
| RIP: 0010:hsr_addr_is_self+0x86/0x330 net/hsr/hsr_framereg.c:44 |
| Code: 04 00 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 45 d0 31 c0 e8 6b ff 94 f9 4c 89 f2 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 75 02 00 00 48 8b 43 30 49 39 c6 49 89 47 c0 0f |
| RSP: 0018:ffffc90000da8a90 EFLAGS: 00010206 |
| RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87e0cc33 |
| RDX: 0000000000000006 RSI: ffffffff87e035d5 RDI: 0000000000000000 |
| RBP: ffffc90000da8b20 R08: ffff88808e7de040 R09: ffffed1015d2707c |
| R10: ffffed1015d2707b R11: ffff8880ae9383db R12: ffff8880a689bc5e |
| R13: 1ffff920001b5153 R14: 0000000000000030 R15: ffffc90000da8af8 |
| FS: 00007fd7a42be700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 0000001b32338000 CR3: 00000000a928c000 CR4: 00000000001406e0 |
| DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 |
| DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 |
| Call Trace: |
| <IRQ> |
| hsr_handle_frame+0x1c5/0x630 net/hsr/hsr_slave.c:31 |
| __netif_receive_skb_core+0xfbc/0x30b0 net/core/dev.c:5099 |
| __netif_receive_skb_one_core+0xa8/0x1a0 net/core/dev.c:5196 |
| __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5312 |
| process_backlog+0x206/0x750 net/core/dev.c:6144 |
| napi_poll net/core/dev.c:6582 [inline] |
| net_rx_action+0x508/0x1120 net/core/dev.c:6650 |
| __do_softirq+0x262/0x98c kernel/softirq.c:292 |
| do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082 |
| </IRQ> |
| |
| Fixes: c5a759117210 ("net/hsr: Use list_head (and rcu) instead of array for slave devices.") |
| Signed-off-by: Eric Dumazet <edumazet@google.com> |
| Reported-by: syzbot <syzkaller@googlegroups.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/hsr/hsr_slave.c | 2 ++ |
| 1 file changed, 2 insertions(+) |
| |
| --- a/net/hsr/hsr_slave.c |
| +++ b/net/hsr/hsr_slave.c |
| @@ -32,6 +32,8 @@ static rx_handler_result_t hsr_handle_fr |
| |
| rcu_read_lock(); /* hsr->node_db, hsr->ports */ |
| port = hsr_port_get_rcu(skb->dev); |
| + if (!port) |
| + goto finish_pass; |
| |
| if (hsr_addr_is_self(port->hsr, eth_hdr(skb)->h_source)) { |
| /* Directly kill frames sent by ourselves */ |