Re: [PATCH v6.6.y 2/2] tls: Use __sk_dst_get() and dst_dev_rcu() in get_netdev_for_sock().

From: Greg KH

Date: Mon Jan 12 2026 - 06:05:53 EST


On Mon, Jan 12, 2026 at 06:45:54AM +0000, Keerthana K wrote:
> From: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
>
> [ Upstream commit c65f27b9c3be2269918e1cbad6d8884741f835c5 ]
>
> get_netdev_for_sock() is called during setsockopt(),
> so not under RCU.
>
> Using sk_dst_get(sk)->dev could trigger UAF.
>
> Let's use __sk_dst_get() and dst_dev_rcu().
>
> Note that the only ->ndo_sk_get_lower_dev() user is
> bond_sk_get_lower_dev(), which uses RCU.
>
> Fixes: e8f69799810c ("net/tls: Add generic NIC offload infrastructure")
> Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
> Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
> Reviewed-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
> Link: https://patch.msgid.link/20250916214758.650211-6-kuniyu@xxxxxxxxxx
> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> [ Keerthana: Backport to v6.6.y ]
> Signed-off-by: Keerthana K <keerthana.kalyanasundaram@xxxxxxxxxxxx>
> ---
> net/tls/tls_device.c | 17 ++++++++++-------
> 1 file changed, 10 insertions(+), 7 deletions(-)

This is not in 6.12.y, so we can't take it for 6.6.y yet. Can you
please send a 6.12.y version and then a new 6.6.y version?

thanks,

greg k-h