syzbot reported NULL ptr dereference in nl802154_del_llsec_key()[1] The problem was in case of info->attrs[NL802154_ATTR_SEC_KEY] == NULL. nla_parse_nested_deprecated()[2] doesn't check this condition before calling nla_len()[3] Call Trace: nla_len include/net/netlink.h:1148 [inline] [3] nla_parse_nested_deprecated include/net/netlink.h:1231 [inline] [2] nl802154_del_llsec_key+0x16d/0x320 net/ieee802154/nl802154.c:1595 [1] genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:739 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline] genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:800 Reported-by: syzbot+ac5c11d2959a8b3c4806@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx> --- net/ieee802154/nl802154.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c index 7c5a1aa5adb4..2f0a138bd5eb 100644 --- a/net/ieee802154/nl802154.c +++ b/net/ieee802154/nl802154.c @@ -1592,7 +1592,8 @@ static int nl802154_del_llsec_key(struct sk_buff *skb, struct genl_info *info) struct nlattr *attrs[NL802154_KEY_ATTR_MAX + 1]; struct ieee802154_llsec_key_id id; - if (nla_parse_nested_deprecated(attrs, NL802154_KEY_ATTR_MAX, info->attrs[NL802154_ATTR_SEC_KEY], nl802154_key_policy, info->extack)) + if (!info->attrs[NL802154_ATTR_SEC_KEY] || + nla_parse_nested_deprecated(attrs, NL802154_KEY_ATTR_MAX, info->attrs[NL802154_ATTR_SEC_KEY], nl802154_key_policy, info->extack)) return -EINVAL; if (ieee802154_llsec_parse_key_id(attrs[NL802154_KEY_ATTR_ID], &id) < 0) -- 2.30.2
