• Jakub Kicinski's avatar
    net: don't clear sock->sk early to avoid trouble in strparser · 2b81f816
    Jakub Kicinski authored
    af_inet sets sock->sk to NULL which trips strparser over:
    
    BUG: kernel NULL pointer dereference, address: 0000000000000012
    PGD 0 P4D 0
    Oops: 0000 [#1] SMP PTI
    CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.2.0-rc1-00139-g14629453a6d3 #21
    RIP: 0010:tcp_peek_len+0x10/0x60
    RSP: 0018:ffffc02e41c54b98 EFLAGS: 00010246
    RAX: 0000000000000000 RBX: ffff9cf924c4e030 RCX: 0000000000000051
    RDX: 0000000000000000 RSI: 000000000000000c RDI: ffff9cf97128f480
    RBP: ffff9cf9365e0300 R08: ffff9cf94fe7d2c0 R09: 0000000000000000
    R10: 000000000000036b R11: ffff9cf939735e00 R12: ffff9cf91ad9ae40
    R13: ffff9cf924c4e000 R14: ffff9cf9a8fcbaae R15: 0000000000000020
    FS: 0000000000000000(0000) GS:ffff9cf9af7c0000(0000) knlGS:0000000000000000
    CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000000000012 CR3: 000000013920a003 CR4: 00000000003606e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
     Call Trace:
     <IRQ>
     strp_data_ready+0x48/0x90
     tls_data_ready+0x22/0xd0 [tls]
     tcp_rcv_established+0x569/0x620
     tcp_v4_do_rcv+0x127/0x1e0
     tcp_v4_rcv+0xad7/0xbf0
     ip_protocol_deliver_rcu+0x2c/0x1c0
     ip_local_deliver_finish+0x41/0x50
     ip_local_deliver+0x6b/0xe0
     ? ip_protocol_deliver_rcu+0x1c0/0x1c0
     ip_rcv+0x52/0xd0
     ? ip_rcv_finish_core.isra.20+0x380/0x380
     __netif_receive_skb_one_core+0x7e/0x90
     netif_receive_skb_internal+0x42/0xf0
     napi_gro_receive+0xed/0x150
     nfp_net_poll+0x7a2/0xd30 [nfp]
     ? kmem_cache_free_bulk+0x286/0x310
     net_rx_action+0x149/0x3b0
     __do_softirq+0xe3/0x30a
     ? handle_irq_event_percpu+0x6a/0x80
     irq_exit+0xe8/0xf0
     do_IRQ+0x85/0xd0
     common_interrupt+0xf/0xf
     </IRQ>
    RIP: 0010:cpuidle_enter_state+0xbc/0x450
    
    To avoid this issue set sock->sk after sk_prot->close.
    My grepping and testing did not discover any code which
    would depend on the current behaviour.
    
    Fixes: c46234eb ("tls: RX path for ktls")
    Reported-by: default avatarDavid Beckett <david.beckett@netronome.com>
    Signed-off-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
    Reviewed-by: default avatarDirk van der Merwe <dirk.vandermerwe@netronome.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    2b81f816
af_inet.c 50.9 KB