From 4b793feccae3b06764268377a4030eb774ed924e Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Mon, 7 Oct 2019 13:26:29 -0700 Subject: [PATCH] net_sched: fix backward compatibility for TCA_ACT_KIND For TCA_ACT_KIND, we have to keep the backward compatibility too, and rely on nla_strlcpy() to check and terminate the string with a NUL. Note for TC actions, nla_strcmp() is already used to compare kind strings, so we don't need to fix other places. Fixes: 199ce850ce11 ("net_sched: add policy validation for action attributes") Reported-by: Marcelo Ricardo Leitner Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski --- net/sched/act_api.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/sched/act_api.c b/net/sched/act_api.c index 2558f00f6b3e..4e7429c6f864 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -832,8 +832,7 @@ static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb) } static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = { - [TCA_ACT_KIND] = { .type = NLA_NUL_STRING, - .len = IFNAMSIZ - 1 }, + [TCA_ACT_KIND] = { .type = NLA_STRING }, [TCA_ACT_INDEX] = { .type = NLA_U32 }, [TCA_ACT_COOKIE] = { .type = NLA_BINARY, .len = TC_COOKIE_MAX_SIZE }, @@ -865,8 +864,10 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, NL_SET_ERR_MSG(extack, "TC action kind must be specified"); goto err_out; } - nla_strlcpy(act_name, kind, IFNAMSIZ); - + if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) { + NL_SET_ERR_MSG(extack, "TC action name too long"); + goto err_out; + } if (tb[TCA_ACT_COOKIE]) { cookie = nla_memdup_cookie(tb); if (!cookie) { -- 2.30.2