[PATCH net V3] net: ping6: Fix ping -6 with interface name

[PATCH net V3] net: ping6: Fix ping -6 with interface name

[Tariq Toukan]

From: Aya Levin <ayal@nvidia.com>

When passing interface parameter to ping -6:
$ ping -6 ::11:141:84:9 -I eth2
Results in:
PING ::11:141:84:10(::11:141:84:10) from ::11:141:84:9 eth2: 56 data bytes
ping: sendmsg: Invalid argument
ping: sendmsg: Invalid argument

Initialize the fl6's outgoing interface (OIF) before triggering
ip6_datagram_send_ctl. Don't wipe fl6 after ip6_datagram_send_ctl() as
changes in fl6 that may happen in the function are overwritten explicitly.
Update comment accordingly.

Fixes: 13651224c00b ("net: ping6: support setting basic SOL_IPV6 options via cmsg")
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 net/ipv6/ping.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

V3:
Per David Ahern's comment, moved fl6.flowi6_oif init to the
shared flow right after the memset.

V2:
Per David Ahern's comment, moved memset before if (msg->msg_controllen),
and updated the code comment accordingly.

diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index ff033d16549e..ecf3a553a0dc 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -101,6 +101,9 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	ipc6.sockc.tsflags = sk->sk_tsflags;
 	ipc6.sockc.mark = sk->sk_mark;
 
+	memset(&fl6, 0, sizeof(fl6));
+	fl6.flowi6_oif = oif;
+
 	if (msg->msg_controllen) {
 		struct ipv6_txoptions opt = {};
 
@@ -112,17 +115,14 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 			return err;
 
 		/* Changes to txoptions and flow info are not implemented, yet.
-		 * Drop the options, fl6 is wiped below.
+		 * Drop the options.
 		 */
 		ipc6.opt = NULL;
 	}
 
-	memset(&fl6, 0, sizeof(fl6));
-
 	fl6.flowi6_proto = IPPROTO_ICMPV6;
 	fl6.saddr = np->saddr;
 	fl6.daddr = *daddr;
-	fl6.flowi6_oif = oif;
 	fl6.flowi6_mark = ipc6.sockc.mark;
 	fl6.flowi6_uid = sk->sk_uid;
 	fl6.fl6_icmp_type = user_icmph.icmp6_type;
-- 
2.21.0

Re: [PATCH net V3] net: ping6: Fix ping -6 with interface name

[David Ahern]

On 5/31/22 2:45 AM, Tariq Toukan wrote:
> From: Aya Levin <ayal@nvidia.com>
> 
> When passing interface parameter to ping -6:
> $ ping -6 ::11:141:84:9 -I eth2
> Results in:
> PING ::11:141:84:10(::11:141:84:10) from ::11:141:84:9 eth2: 56 data bytes
> ping: sendmsg: Invalid argument
> ping: sendmsg: Invalid argument
> 
> Initialize the fl6's outgoing interface (OIF) before triggering
> ip6_datagram_send_ctl. Don't wipe fl6 after ip6_datagram_send_ctl() as
> changes in fl6 that may happen in the function are overwritten explicitly.
> Update comment accordingly.
> 
> Fixes: 13651224c00b ("net: ping6: support setting basic SOL_IPV6 options via cmsg")
> Signed-off-by: Aya Levin <ayal@nvidia.com>
> Reviewed-by: Gal Pressman <gal@nvidia.com>
> Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
> ---
>  net/ipv6/ping.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> V3:
> Per David Ahern's comment, moved fl6.flowi6_oif init to the
> shared flow right after the memset.
> 
> V2:
> Per David Ahern's comment, moved memset before if (msg->msg_controllen),
> and updated the code comment accordingly.
> 

Reviewed-by: David Ahern <dsahern@kernel.org>

The patch set with the Fixes tag added selftests using cmsg_sender.c.
You can extend it to support IPV6_PKTINFO and submit a selftest for this
case to -next when it opens.

Re: [PATCH net V3] net: ping6: Fix ping -6 with interface name

[Aya Levin]

On 5/31/2022 5:31 PM, David Ahern wrote:
> On 5/31/22 2:45 AM, Tariq Toukan wrote:
>> From: Aya Levin <ayal@nvidia.com>
>>
>> When passing interface parameter to ping -6:
>> $ ping -6 ::11:141:84:9 -I eth2
>> Results in:
>> PING ::11:141:84:10(::11:141:84:10) from ::11:141:84:9 eth2: 56 data bytes
>> ping: sendmsg: Invalid argument
>> ping: sendmsg: Invalid argument
>>
>> Initialize the fl6's outgoing interface (OIF) before triggering
>> ip6_datagram_send_ctl. Don't wipe fl6 after ip6_datagram_send_ctl() as
>> changes in fl6 that may happen in the function are overwritten explicitly.
>> Update comment accordingly.
>>
>> Fixes: 13651224c00b ("net: ping6: support setting basic SOL_IPV6 options via cmsg")
>> Signed-off-by: Aya Levin <ayal@nvidia.com>
>> Reviewed-by: Gal Pressman <gal@nvidia.com>
>> Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
>> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
>> ---
>>   net/ipv6/ping.c | 8 ++++----
>>   1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> V3:
>> Per David Ahern's comment, moved fl6.flowi6_oif init to the
>> shared flow right after the memset.
>>
>> V2:
>> Per David Ahern's comment, moved memset before if (msg->msg_controllen),
>> and updated the code comment accordingly.
>>
> 
> Reviewed-by: David Ahern <dsahern@kernel.org>
Thanks for the review.
> 
> The patch set with the Fixes tag added selftests using cmsg_sender.c.
> You can extend it to support IPV6_PKTINFO and submit a selftest for this
> case to -next when it opens.
I'll submit the selftest extension in the coming window
Aya

Re: [PATCH net V3] net: ping6: Fix ping -6 with interface name

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (master)
by Paolo Abeni <pabeni@redhat.com>:

On Tue, 31 May 2022 11:45:44 +0300 you wrote:
> From: Aya Levin <ayal@nvidia.com>
> 
> When passing interface parameter to ping -6:
> $ ping -6 ::11:141:84:9 -I eth2
> Results in:
> PING ::11:141:84:10(::11:141:84:10) from ::11:141:84:9 eth2: 56 data bytes
> ping: sendmsg: Invalid argument
> ping: sendmsg: Invalid argument
> 
> [...]

Here is the summary with links:
  - [net,V3] net: ping6: Fix ping -6 with interface name
    https://git.kernel.org/netdev/net/c/e6652a8ef3e6

You are awesome, thank you!
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