netdev - Re: [PATCH net] net: sungem: fix rx checksum support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Mon, 27 Aug 2018 09:57:30 -0700
From:   Eric Dumazet <edumazet@...gle.com>
To:     Meelis Roos <mroos@...ux.ee>
Cc:     Eric Dumazet <eric.dumazet@...il.com>,
        David Miller <davem@...emloft.net>,
        netdev <netdev@...r.kernel.org>,
        Mathieu Malaterre <malat@...ian.org>,
        Andreas Schwab <schwab@...ux-m68k.org>
Subject: Re: [PATCH net] net: sungem: fix rx checksum support

On Sun, Aug 26, 2018 at 6:14 AM <mroos@...ux.ee> wrote:
>
> > BTW, removing the FCS also means GRO is going to work, finally on this NIC ;)
> >
> > GRO does not like packets with padding.
>
> As a follow-up, I am seeing hw csum failures on Sun V440 that has
> onboard Sun Cassini with sungem driver. First tested version was 4.18
> (it happened there once) and now that I tried 4.18+git, it still
> happens:
>
> [   21.563282] libphy: Fixed MDIO Bus: probed
> [   21.617116] cassini: cassini.c:v1.6 (21 May 2008)
> [   21.678962] cassini 0000:00:02.0: enabling device (0144 -> 0146)
> [   21.761931] cassini 0000:00:02.0 eth0: Sun Cassini+ (64bit/66MHz PCI/Cu) Ethernet[6] 00:03:ba:6f:14:39
> [   21.884952] cassini 0003:00:01.0: enabling device (0144 -> 0146)
> [   21.967868] cassini 0003:00:01.0 eth1: Sun Cassini+ (64bit/66MHz PCI/Cu) Ethernet[29] 00:03:ba:6f:14:3a
> [...]
> [   54.341212] eth0: hw csum failure
> [   54.384725] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.18.0-12952-g2923b27 #1397
> [   54.483167] Call Trace:
> [   54.515209]  [000000000077838c] __skb_checksum_complete+0xcc/0xe0
> [   54.595272]  [000000000080fc84] igmp_rcv+0x224/0x920
> [   54.660475]  [00000000007ca3d0] ip_local_deliver+0xb0/0x240
> [   54.733675]  [00000000007ca5c0] ip_rcv+0x60/0xa0
> [   54.794304]  [0000000000781a30] __netif_receive_skb_one_core+0x30/0x60
> [   54.880094]  [0000000000782914] process_backlog+0x94/0x140
> [   54.952161]  [0000000000788f6c] net_rx_action+0x1ec/0x320
> [   55.023083]  [0000000000870de8] __do_softirq+0xc8/0x200
> [   55.091719]  [000000000042c4cc] do_softirq_own_stack+0x2c/0x40
> [   55.168362]  [00000000004662d8] irq_exit+0xb8/0xe0
> [   55.231266]  [0000000000870ac0] handler_irq+0xc0/0x100
> [   55.298756]  [00000000004208b4] tl0_irq5+0x14/0x20
> [   55.361670]  [000000000042cafc] arch_cpu_idle+0x9c/0xa0
> [   55.447055]  [000000000048a254] cpu_startup_entry+0x14/0x40
> [   55.536998]  [000000000095f4b4] 0x95f4b4
> [   55.588471]  [0000000040000000] 0x40000000
> [  179.780371] eth0: hw csum failure
> [  179.823878] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.18.0-12952-g2923b27 #1397
> [  179.922230] Call Trace:
> [  179.954267]  [000000000077838c] __skb_checksum_complete+0xcc/0xe0
> [  180.034335]  [000000000080fc84] igmp_rcv+0x224/0x920
> [  180.099536]  [00000000007ca3d0] ip_local_deliver+0xb0/0x240
> [  180.172740]  [00000000007ca5c0] ip_rcv+0x60/0xa0
> [  180.233368]  [0000000000781a30] __netif_receive_skb_one_core+0x30/0x60
> [  180.319159]  [0000000000782914] process_backlog+0x94/0x140
> [  180.391225]  [0000000000788f6c] net_rx_action+0x1ec/0x320
> [  180.462148]  [0000000000870de8] __do_softirq+0xc8/0x200
> [  180.530782]  [000000000042c4cc] do_softirq_own_stack+0x2c/0x40
> [  180.607422]  [00000000004662d8] irq_exit+0xb8/0xe0
> [  180.670331]  [0000000000870ac0] handler_irq+0xc0/0x100
> [  180.737822]  [00000000004208b4] tl0_irq5+0x14/0x20
> [  180.800735]  [000000000042caf8] arch_cpu_idle+0x98/0xa0
> [  180.869373]  [0000000000489f60] do_idle+0xe0/0x1c0
> [  180.932281]  [000000000048a25c] cpu_startup_entry+0x1c/0x40
> [  181.005491]  [000000000098e9b4] start_kernel+0x3b8/0x3c8


Note that these traces are for non TCP packets.

I suspect the driver should not provide CHECKSUM_COMPLETE for non TCP
packets, maybe the NIC is mishandling this case.