From: Alexander Aring <aahringo@xxxxxxxxxx> commit 6f7f657f24405f426212c09260bf7fe8a52cef33 upstream. This patch fixes a null pointer derefence for panid handle by move the check for the netlink variable directly before accessing them. Reported-by: syzbot+d4c07de0144f6f63be3a@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Alexander Aring <aahringo@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210228151817.95700-4-aahringo@xxxxxxxxxx Signed-off-by: Stefan Schmidt <stefan@xxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ieee802154/nl-mac.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/net/ieee802154/nl-mac.c +++ b/net/ieee802154/nl-mac.c @@ -557,9 +557,7 @@ ieee802154_llsec_parse_key_id(struct gen desc->mode = nla_get_u8(info->attrs[IEEE802154_ATTR_LLSEC_KEY_MODE]); if (desc->mode == IEEE802154_SCF_KEY_IMPLICIT) { - if (!info->attrs[IEEE802154_ATTR_PAN_ID] && - !(info->attrs[IEEE802154_ATTR_SHORT_ADDR] || - info->attrs[IEEE802154_ATTR_HW_ADDR])) + if (!info->attrs[IEEE802154_ATTR_PAN_ID]) return -EINVAL; desc->device_addr.pan_id = nla_get_shortaddr(info->attrs[IEEE802154_ATTR_PAN_ID]); @@ -568,6 +566,9 @@ ieee802154_llsec_parse_key_id(struct gen desc->device_addr.mode = IEEE802154_ADDR_SHORT; desc->device_addr.short_addr = nla_get_shortaddr(info->attrs[IEEE802154_ATTR_SHORT_ADDR]); } else { + if (!info->attrs[IEEE802154_ATTR_HW_ADDR]) + return -EINVAL; + desc->device_addr.mode = IEEE802154_ADDR_LONG; desc->device_addr.extended_addr = nla_get_hwaddr(info->attrs[IEEE802154_ATTR_HW_ADDR]); }
