From: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
To: Guillaume Nault <gnault@redhat.com>
Cc: netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
Shuah Khan <shuah@kernel.org>,
linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: POSSIBLE BUG: selftests/net/fcnal-test.sh: [FAIL][FIX TESTED] in vrf "bind - ns-B IPv6 LLA" test
Date: Tue, 6 Jun 2023 20:07:36 +0200 [thread overview]
Message-ID: <48cfd903-ad2f-7da7-e5a6-a22392dc8650@alu.unizg.hr> (raw)
In-Reply-To: <ZH84zGEODT97TEXG@debian>
On 6/6/23 15:46, Guillaume Nault wrote:
> On Tue, Jun 06, 2023 at 08:24:54AM +0200, Mirsad Goran Todorovac wrote:
>> On 5/31/23 20:11, Guillaume Nault wrote:
>>> I believe this condition should be relaxed to allow the case where
>>> ->sk_bound_dev_if is oif's master device (and maybe there are other
>>> VRF cases to also consider).
>>
>> I've tried something like this, but something makes the kernel stuck
>> here:
>>
>> TEST: ping out, blocked by route - ns-B loopback IPv6 [ OK ]
>> TEST: ping out, device bind, blocked by route - ns-B loopback IPv6 [ OK ]
>> TEST: ping in, blocked by route - ns-A loopback IPv6 [ OK ]
>> TEST: ping out, unreachable route - ns-B loopback IPv6 [ OK ]
>> TEST: ping out, device bind, unreachable route - ns-B loopback IPv6 [ OK ]
>>
>> #################################################################
>> With VRF
>>
>> [hanged process and kernel won't shutdown]
>>
>> The code is:
>>
>> ---
>> net/ipv6/ping.c | 12 +++++++++++-
>> 1 file changed, 11 insertions(+), 1 deletion(-)
>>
>> diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
>> index c4835dbdfcff..81293e902293 100644
>> --- a/net/ipv6/ping.c
>> +++ b/net/ipv6/ping.c
>> @@ -73,6 +73,9 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
>> struct rt6_info *rt;
>> struct pingfakehdr pfh;
>> struct ipcm6_cookie ipc6;
>> + struct net *net = sock_net(sk);
>> + struct net_device *dev = NULL;
>> + struct net_device *mdev = NULL;
>> err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
>> sizeof(user_icmph));
>> @@ -111,10 +114,17 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
>> else if (!oif)
>> oif = np->ucast_oif;
>> + if (oif) {
>> + dev = dev_get_by_index(net, oif);
>> + mdev = netdev_master_upper_dev_get(dev);
>> + }
>> +
>> addr_type = ipv6_addr_type(daddr);
>> if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) ||
>> (addr_type & IPV6_ADDR_MAPPED) ||
>> - (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if))
>> + (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if &&
>> + !(mdev && sk->sk_bound_dev_if &&
>> + mdev != dev_get_by_index(net, sk->sk_bound_dev_if))))
>> return -EINVAL;
>> ipcm6_init_sk(&ipc6, np);
>>
>> I am obviously doing something very stupid.
>
> The problem is that dev_get_by_index() holds a reference on 'dev' which
> your code never releases. Also netdev_master_upper_dev_get() needs rtnl
> protection. These should have generated some kernel oops.
>
> You can try this instead:
>
> -------- >8 --------
>
> diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
> index c4835dbdfcff..f804c11e2146 100644
> --- a/net/ipv6/ping.c
> +++ b/net/ipv6/ping.c
> @@ -114,7 +114,8 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
> addr_type = ipv6_addr_type(daddr);
> if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) ||
> (addr_type & IPV6_ADDR_MAPPED) ||
> - (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if))
> + (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if &&
> + l3mdev_master_ifindex_by_index(sock_net(sk), oif) != sk->sk_bound_dev_if))
> return -EINVAL;
>
> ipcm6_init_sk(&ipc6, np);
The problem appears to be fixed:
# ./fcnal-test.sh
[...]
TEST: ping out, vrf device+address bind - ns-B loopback IPv6 [ OK ]
TEST: ping out, vrf device+address bind - ns-B IPv6 LLA [ OK ]
TEST: ping in - ns-A IPv6 [ OK ]
[...]
Tests passed: 888
Tests failed: 0
#
The test passed in both environments that manifested the bug.
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
However, test on my AMD Ubuntu 22.04 box with 6.4-rc5 commit a4d7d7011219
has shown additional four failed tests:
root@host # grep -n FAIL ../fcnal-test-4.log
90:TEST: ping local, VRF bind - VRF IP [FAIL]
92:TEST: ping local, device bind - ns-A IP [FAIL]
116:TEST: ping local, VRF bind - VRF IP [FAIL]
118:TEST: ping local, device bind - ns-A IP [FAIL]
root@host #
But you would probably want me to file a separate bug report?
Best regards,
Mirsad
next prev parent reply other threads:[~2023-06-06 18:08 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-24 12:17 POSSIBLE BUG: selftests/net/fcnal-test.sh: [FAIL] in vrf "bind - ns-B IPv6 LLA" test Mirsad Todorovac
2023-05-31 18:11 ` Guillaume Nault
2023-06-02 12:35 ` Mirsad Goran Todorovac
2023-06-06 6:24 ` Mirsad Goran Todorovac
2023-06-06 13:46 ` Guillaume Nault
2023-06-06 13:57 ` Mirsad Todorovac
2023-06-06 14:11 ` Guillaume Nault
2023-06-06 14:28 ` Mirsad Todorovac
2023-06-06 18:50 ` Guillaume Nault
2023-06-06 19:17 ` Mirsad Goran Todorovac
2023-06-06 19:27 ` Guillaume Nault
2023-06-06 18:07 ` Mirsad Goran Todorovac [this message]
2023-06-06 18:57 ` POSSIBLE BUG: selftests/net/fcnal-test.sh: [FAIL][FIX TESTED] " Guillaume Nault
2023-06-06 22:04 ` Mirsad Goran Todorovac
2023-06-07 16:51 ` Guillaume Nault
2023-06-08 5:37 ` Mirsad Goran Todorovac
2023-06-09 16:13 ` Guillaume Nault
2023-06-10 18:04 ` Mirsad Goran Todorovac
2023-06-14 8:47 ` Guillaume Nault
2023-06-15 20:10 ` Mirsad Goran Todorovac
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=48cfd903-ad2f-7da7-e5a6-a22392dc8650@alu.unizg.hr \
--to=mirsad.todorovac@alu.unizg.hr \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=gnault@redhat.com \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=shuah@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).