On Thu, Oct 10, 2019 at 11:31:53AM +0200, Jiri Pirko wrote: > Wed, Oct 09, 2019 at 06:44:32PM CEST, [email protected] wrote: > >Commit c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing > >to a separate function") moved attribute buffer allocation and attribute > >parsing from genl_family_rcv_msg_doit() into a separate function > >genl_family_rcv_msg_attrs_parse() which, unlike the previous code, calls > >__nlmsg_parse() even if family->maxattr is 0 (i.e. the family does its own > >parsing). The parser error is ignored and does not propagate out of > >genl_family_rcv_msg_attrs_parse() but an error message ("Unknown attribute > >type") is set in extack and if further processing generates no error or > >warning, it stays there and is interpreted as a warning by userspace. > > > >Dumpit requests are not affected as genl_family_rcv_msg_dumpit() bypasses > >the call of genl_family_rcv_msg_doit() if family->maxattr is zero. Do the > >same also in genl_family_rcv_msg_doit(). > > > >Fixes: c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing to > >a separate function") > >Signed-off-by: Michal Kubecek <[email protected]> > >--- > > net/netlink/genetlink.c | 6 ++++-- > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > >diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c > >index ecc2bd3e73e4..c4bf8830eedf 100644 > >--- a/net/netlink/genetlink.c > >+++ b/net/netlink/genetlink.c > >@@ -639,21 +639,23 @@ static int genl_family_rcv_msg_doit(const struct > >genl_family *family, > > const struct genl_ops *ops, > > int hdrlen, struct net *net) > > { > >- struct nlattr **attrbuf; > >+ struct nlattr **attrbuf = NULL; > > struct genl_info info; > > int err; > > > > if (!ops->doit) > > return -EOPNOTSUPP; > > > >+ if (!family->maxattr) > >+ goto no_attrs; > > attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack, > > ops, hdrlen, > > GENL_DONT_VALIDATE_STRICT, > >- family->maxattr && > > family->parallel_ops); > > Please also adjust genl_family_rcv_msg_attrs_free() call arg > below in this function in the similar way.
Sent v2. Michal
