From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> commit 18917d51472fe3b126a3a8f756c6b18085eb8130 upstream. nfc_genl_deactivate_target() relies on the NFC_ATTR_TARGET_INDEX attribute being present, but doesn't check whether it is actually provided by the user. Same goes for nfc_genl_fw_download() and NFC_ATTR_FIRMWARE_NAME. This patch adds appropriate checks. Found with syzkaller. Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/nfc/netlink.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/nfc/netlink.c +++ b/net/nfc/netlink.c @@ -936,7 +936,8 @@ static int nfc_genl_dep_link_down(struct int rc; u32 idx; - if (!info->attrs[NFC_ATTR_DEVICE_INDEX]) + if (!info->attrs[NFC_ATTR_DEVICE_INDEX] || + !info->attrs[NFC_ATTR_TARGET_INDEX]) return -EINVAL; idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]); @@ -985,7 +986,8 @@ static int nfc_genl_llc_get_params(struc struct sk_buff *msg = NULL; u32 idx; - if (!info->attrs[NFC_ATTR_DEVICE_INDEX]) + if (!info->attrs[NFC_ATTR_DEVICE_INDEX] || + !info->attrs[NFC_ATTR_FIRMWARE_NAME]) return -EINVAL; idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);