ethtool: pse-pd: fix null-deref on genl_info in dump

ethnl_default_dump_one() passes NULL as info.

It's correct not to set extack during dump, as we should just
silently skip interfaces which can't provide the information.

Reported-by: syzbot+81c4b4bbba6eea2cfcae@syzkaller.appspotmail.com
Fixes: 18ff0bcda6d1 ("ethtool: add interface to interact with Ethernet Power Equipment")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ethtool/pse-pd.c b/net/ethtool/pse-pd.c
index 5a471e1..e8683e4 100644 (file)
--- a/net/ethtool/pse-pd.c
+++ b/net/ethtool/pse-pd.c
@@ -64,7 +64,7 @@ static int pse_prepare_data(const struct ethnl_req_info *req_base,
        if (ret < 0)
                return ret;
 
-       ret = pse_get_pse_attributes(dev, info->extack, data);
+       ret = pse_get_pse_attributes(dev, info ? info->extack : NULL, data);
 
        ethnl_ops_complete(dev);