act_simple, act_mpls, act_nat, act_skbmod and act_connmark each have a tcf_*_dump but no .get_fill_size callback, so tcf_action_fill_size budgets only the shared attributes and omits the per-action TCA_*_PARMS and option bytes the dump emits. Add a callback to each, sized from the attributes its dump emits. Size every optional attribute unconditionally: reading the current flags to size it conditionally would race a concurrent replace, which can flip the attributes between sizing and dumping. Reported-by: Sashiko Link: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260824153903.4143642-1-victor@mojatatu.com Co-developed-by: Jamal Hadi Salim Signed-off-by: Jamal Hadi Salim Signed-off-by: Victor Nogueira --- net/sched/act_connmark.c | 6 ++++++ net/sched/act_mpls.c | 11 +++++++++++ net/sched/act_nat.c | 6 ++++++ net/sched/act_simple.c | 7 +++++++ net/sched/act_skbmod.c | 9 +++++++++ 5 files changed, 39 insertions(+) diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c index c634af5edfcd..0b6ac6be60d2 100644 --- a/net/sched/act_connmark.c +++ b/net/sched/act_connmark.c @@ -236,12 +236,18 @@ static void tcf_connmark_cleanup(struct tc_action *a) kfree_rcu(parms, rcu); } +static size_t tcf_connmark_get_fill_size(const struct tc_action *act) +{ + return nla_total_size(sizeof(struct tc_connmark)); /* TCA_CONNMARK_PARMS */ +} + static struct tc_action_ops act_connmark_ops = { .kind = "connmark", .id = TCA_ID_CONNMARK, .owner = THIS_MODULE, .act = tcf_connmark_act, .dump = tcf_connmark_dump, + .get_fill_size = tcf_connmark_get_fill_size, .init = tcf_connmark_init, .cleanup = tcf_connmark_cleanup, .size = sizeof(struct tcf_connmark_info), diff --git a/net/sched/act_mpls.c b/net/sched/act_mpls.c index 4ea8b2e08c3a..aa56521b7179 100644 --- a/net/sched/act_mpls.c +++ b/net/sched/act_mpls.c @@ -438,12 +438,23 @@ static int tcf_mpls_offload_act_setup(struct tc_action *act, void *entry_data, return 0; } +static size_t tcf_mpls_get_fill_size(const struct tc_action *act) +{ + return nla_total_size(sizeof(struct tc_mpls)) /* TCA_MPLS_PARMS */ + + nla_total_size(sizeof(u32)) /* TCA_MPLS_LABEL */ + + nla_total_size(sizeof(u8)) /* TCA_MPLS_TC */ + + nla_total_size(sizeof(u8)) /* TCA_MPLS_TTL */ + + nla_total_size(sizeof(u8)) /* TCA_MPLS_BOS */ + + nla_total_size(sizeof(u16)); /* TCA_MPLS_PROTO */ +} + static struct tc_action_ops act_mpls_ops = { .kind = "mpls", .id = TCA_ID_MPLS, .owner = THIS_MODULE, .act = tcf_mpls_act, .dump = tcf_mpls_dump, + .get_fill_size = tcf_mpls_get_fill_size, .init = tcf_mpls_init, .cleanup = tcf_mpls_cleanup, .offload_act_setup = tcf_mpls_offload_act_setup, diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c index abb332dee836..a201979ac7cf 100644 --- a/net/sched/act_nat.c +++ b/net/sched/act_nat.c @@ -313,12 +313,18 @@ static void tcf_nat_cleanup(struct tc_action *a) kfree_rcu(parms, rcu); } +static size_t tcf_nat_get_fill_size(const struct tc_action *act) +{ + return nla_total_size(sizeof(struct tc_nat)); /* TCA_NAT_PARMS */ +} + static struct tc_action_ops act_nat_ops = { .kind = "nat", .id = TCA_ID_NAT, .owner = THIS_MODULE, .act = tcf_nat_act, .dump = tcf_nat_dump, + .get_fill_size = tcf_nat_get_fill_size, .init = tcf_nat_init, .cleanup = tcf_nat_cleanup, .size = sizeof(struct tcf_nat), diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c index 8e69a919b4fe..80e5084b4dbd 100644 --- a/net/sched/act_simple.c +++ b/net/sched/act_simple.c @@ -79,6 +79,12 @@ static int reset_policy(struct tc_action *a, const struct nlattr *defdata, return 0; } +static size_t tcf_simp_get_fill_size(const struct tc_action *act) +{ + return nla_total_size(sizeof(struct tc_defact)) /* TCA_DEF_PARMS */ + + nla_total_size(SIMP_MAX_DATA); /* TCA_DEF_DATA */ +} + static const struct nla_policy simple_policy[TCA_DEF_MAX + 1] = { [TCA_DEF_PARMS] = { .len = sizeof(struct tc_defact) }, [TCA_DEF_DATA] = { .type = NLA_STRING, .len = SIMP_MAX_DATA }, @@ -204,6 +210,7 @@ static struct tc_action_ops act_simp_ops = { .owner = THIS_MODULE, .act = tcf_simp_act, .dump = tcf_simp_dump, + .get_fill_size = tcf_simp_get_fill_size, .cleanup = tcf_simp_release, .init = tcf_simp_init, .size = sizeof(struct tcf_defact), diff --git a/net/sched/act_skbmod.c b/net/sched/act_skbmod.c index 7579cf1e0ff3..09e9dcf58253 100644 --- a/net/sched/act_skbmod.c +++ b/net/sched/act_skbmod.c @@ -279,12 +279,21 @@ static int tcf_skbmod_dump(struct sk_buff *skb, struct tc_action *a, return -1; } +static size_t tcf_skbmod_get_fill_size(const struct tc_action *act) +{ + return nla_total_size(sizeof(struct tc_skbmod)) /* TCA_SKBMOD_PARMS */ + + nla_total_size(ETH_ALEN) /* TCA_SKBMOD_DMAC */ + + nla_total_size(ETH_ALEN) /* TCA_SKBMOD_SMAC */ + + nla_total_size(sizeof(u16)); /* TCA_SKBMOD_ETYPE */ +} + static struct tc_action_ops act_skbmod_ops = { .kind = "skbmod", .id = TCA_ACT_SKBMOD, .owner = THIS_MODULE, .act = tcf_skbmod_act, .dump = tcf_skbmod_dump, + .get_fill_size = tcf_skbmod_get_fill_size, .init = tcf_skbmod_init, .cleanup = tcf_skbmod_cleanup, .size = sizeof(struct tcf_skbmod), -- 2.43.0