From: Navid Emamdoost <navid.emamdoost@xxxxxxxxx> [ Upstream commit 31edf4bbe0ba27fd03ac7d87eb2ee3d2a231af6d ] nla_nest_start() may fail and return NULL. Insert a check and set errno based on other call sites within the same source code. Signed-off-by: Navid Emamdoost <navid.emamdoost@xxxxxxxxx> Reviewed-by: Michal Kubecek <mkubecek@xxxxxxx> Fixes: 47d902b90a32 ("nbd: add a status netlink command") Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240218042534.it.206-kees@xxxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/block/nbd.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index aa65313aabb8d..df738eab02433 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -2437,6 +2437,12 @@ static int nbd_genl_status(struct sk_buff *skb, struct genl_info *info) } dev_list = nla_nest_start_noflag(reply, NBD_ATTR_DEVICE_LIST); + if (!dev_list) { + nlmsg_free(reply); + ret = -EMSGSIZE; + goto out; + } + if (index == -1) { ret = idr_for_each(&nbd_index_idr, &status_cb, reply); if (ret) { -- 2.43.0