| Message ID | 20240606145908.720741-1-dw@davidwei.uk (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 5add2f7288468f35a374620dabf126c13baaea9c |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] netdevsim: fix backwards compatibility in nsim_get_iflink() | expand |
Hello: This patch was applied to netdev/net.git (main) by David S. Miller <davem@davemloft.net>: On Thu, 6 Jun 2024 07:59:08 -0700 you wrote: > The default ndo_get_iflink() implementation returns the current ifindex > of the netdev. But the overridden nsim_get_iflink() returns 0 if the > current nsim is not linked, breaking backwards compatibility for > userspace that depend on this behaviour. > > Fix the problem by returning the current ifindex if not linked to a > peer. > > [...] Here is the summary with links: - [net] netdevsim: fix backwards compatibility in nsim_get_iflink() https://git.kernel.org/netdev/net/c/5add2f728846 You are awesome, thank you!
diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c index c22897bf5509..017a6102be0a 100644 --- a/drivers/net/netdevsim/netdev.c +++ b/drivers/net/netdevsim/netdev.c @@ -324,7 +324,8 @@ static int nsim_get_iflink(const struct net_device *dev) rcu_read_lock(); peer = rcu_dereference(nsim->peer); - iflink = peer ? READ_ONCE(peer->netdev->ifindex) : 0; + iflink = peer ? READ_ONCE(peer->netdev->ifindex) : + READ_ONCE(dev->ifindex); rcu_read_unlock(); return iflink;
The default ndo_get_iflink() implementation returns the current ifindex of the netdev. But the overridden nsim_get_iflink() returns 0 if the current nsim is not linked, breaking backwards compatibility for userspace that depend on this behaviour. Fix the problem by returning the current ifindex if not linked to a peer. Fixes: 8debcf5832c3 ("netdevsim: add ndo_get_iflink() implementation") Reported-by: Yu Watanabe <watanabe.yu@gmail.com> Suggested-by: Yu Watanabe <watanabe.yu@gmail.com> Signed-off-by: David Wei <dw@davidwei.uk> --- drivers/net/netdevsim/netdev.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)