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_attrs_parse() if family->maxattr is zero.
Move this logic inside genl_family_rcv_msg_attrs_parse() so that we don't
have to handle it in each caller.
v3: put the check inside genl_family_rcv_msg_attrs_parse()
v2: adjust also argument of genl_family_rcv_msg_attrs_free()
Fixes: c10e6cf85e7d ("net: genetlink: push attrbuf allocation and parsing to a
separate function")
Signed-off-by: Michal Kubecek <mkube...@suse.cz>
---
net/netlink/genetlink.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index ecc2bd3e73e4..0522b2b1fd95 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -483,6 +483,9 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family
*family,
struct nlattr **attrbuf;
int err;
+ if (!family->maxattr)
+ return NULL;
+
if (parallel) {
attrbuf = kmalloc_array(family->maxattr + 1,
sizeof(struct nlattr *), GFP_KERNEL);
@@ -582,9 +585,6 @@ static int genl_family_rcv_msg_dumpit(const struct
genl_family *family,
if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
return -EINVAL;
- if (!family->maxattr)
- goto no_attrs;
-
attrs = genl_family_rcv_msg_attrs_parse(family, nlh, extack,
ops, hdrlen,
GENL_DONT_VALIDATE_DUMP_STRICT,
@@ -649,7 +649,6 @@ static int genl_family_rcv_msg_doit(const struct
genl_family *family,
attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack,
ops, hdrlen,
GENL_DONT_VALIDATE_STRICT,
- family->maxattr &&
family->parallel_ops);
if (IS_ERR(attrbuf))
return PTR_ERR(attrbuf);
@@ -676,8 +675,7 @@ static int genl_family_rcv_msg_doit(const struct
genl_family *family,
family->post_doit(ops, skb, &info);
out:
- genl_family_rcv_msg_attrs_free(family, attrbuf,
- family->maxattr && family->parallel_ops);
+ genl_family_rcv_msg_attrs_free(family, attrbuf, family->parallel_ops);
return err;
}
--
2.23.0
