if_pfsync: lock buckets during pfsync_drop()

We failed to lock buckets while dropping messages, which could potentially lead
to crashes, and is the likely cause of panics like:

> pfsync_drop: st->sync_state == q
> # pfsync_drop
> # pfsync_q_ins
> # pfsync_insert_state
> # pf_state_insert
> ...

Handle this by only handling the currently relevant (and this locked) bucket.
This ensures that the bucket is locked while we manipulate it.
While here also log slightly more information in the KASSERT().

MFC after:	2 weeks
Sponsored by:	Orange Business Services

(cherry picked from commit 5f75cd390a67cbec06993c4c66f784f0f777c854)
This commit is contained in:
Kristof Provost 2024-07-07 16:42:48 +02:00 committed by Franco Fichtner
parent 2fb39e6bbe
commit c7d09f16cc

View file

@ -345,7 +345,8 @@ static void pfsync_defer_tmo(void *);
static void pfsync_request_update(u_int32_t, u_int64_t);
static bool pfsync_update_state_req(struct pf_kstate *);
static void pfsync_drop(struct pfsync_softc *);
static void pfsync_drop_all(struct pfsync_softc *);
static void pfsync_drop(struct pfsync_softc *, int);
static void pfsync_sendout(int, int);
static void pfsync_send_plus(void *, size_t);
@ -485,7 +486,7 @@ pfsync_clone_destroy(struct ifnet *ifp)
bpfdetach(ifp);
if_detach(ifp);
pfsync_drop(sc);
pfsync_drop_all(sc);
if_free(ifp);
pfsync_multicast_cleanup(sc);
@ -1736,40 +1737,54 @@ pfsync_out_del_c(struct pf_kstate *st, void *buf)
}
static void
pfsync_drop(struct pfsync_softc *sc)
pfsync_drop_all(struct pfsync_softc *sc)
{
struct pfsync_bucket *b;
int c;
for (c = 0; c < pfsync_buckets; c++) {
b = &sc->sc_buckets[c];
PFSYNC_BUCKET_LOCK(b);
pfsync_drop(sc, c);
PFSYNC_BUCKET_UNLOCK(b);
}
}
static void
pfsync_drop(struct pfsync_softc *sc, int c)
{
struct pf_kstate *st, *next;
struct pfsync_upd_req_item *ur;
struct pfsync_bucket *b;
int c;
enum pfsync_q_id q;
for (c = 0; c < pfsync_buckets; c++) {
b = &sc->sc_buckets[c];
for (q = 0; q < PFSYNC_Q_COUNT; q++) {
if (TAILQ_EMPTY(&b->b_qs[q]))
continue;
b = &sc->sc_buckets[c];
PFSYNC_BUCKET_LOCK_ASSERT(b);
TAILQ_FOREACH_SAFE(st, &b->b_qs[q], sync_list, next) {
KASSERT(st->sync_state == pfsync_qid_sstate[q],
("%s: st->sync_state == q",
__func__));
st->sync_state = PFSYNC_S_NONE;
pf_release_state(st);
}
TAILQ_INIT(&b->b_qs[q]);
for (q = 0; q < PFSYNC_Q_COUNT; q++) {
if (TAILQ_EMPTY(&b->b_qs[q]))
continue;
TAILQ_FOREACH_SAFE(st, &b->b_qs[q], sync_list, next) {
KASSERT(st->sync_state == pfsync_qid_sstate[q],
("%s: st->sync_state %d == q %d",
__func__, st->sync_state, q));
st->sync_state = PFSYNC_S_NONE;
pf_release_state(st);
}
while ((ur = TAILQ_FIRST(&b->b_upd_req_list)) != NULL) {
TAILQ_REMOVE(&b->b_upd_req_list, ur, ur_entry);
free(ur, M_PFSYNC);
}
b->b_len = PFSYNC_MINPKT;
free(b->b_plus, M_PFSYNC);
b->b_plus = NULL;
b->b_pluslen = 0;
TAILQ_INIT(&b->b_qs[q]);
}
while ((ur = TAILQ_FIRST(&b->b_upd_req_list)) != NULL) {
TAILQ_REMOVE(&b->b_upd_req_list, ur, ur_entry);
free(ur, M_PFSYNC);
}
b->b_len = PFSYNC_MINPKT;
free(b->b_plus, M_PFSYNC);
b->b_plus = NULL;
b->b_pluslen = 0;
}
static void
@ -1793,7 +1808,7 @@ pfsync_sendout(int schedswi, int c)
PFSYNC_BUCKET_LOCK_ASSERT(b);
if (!bpf_peers_present(ifp->if_bpf) && sc->sc_sync_if == NULL) {
pfsync_drop(sc);
pfsync_drop(sc, c);
return;
}
@ -1841,6 +1856,7 @@ pfsync_sendout(int schedswi, int c)
#endif
default:
m_freem(m);
pfsync_drop(sc, c);
return;
}
m->m_len = m->m_pkthdr.len = len;
@ -2401,8 +2417,8 @@ pfsync_q_ins(struct pf_kstate *st, int sync_state, bool ref)
}
b->b_len += nlen;
TAILQ_INSERT_TAIL(&b->b_qs[q], st, sync_list);
st->sync_state = pfsync_qid_sstate[q];
TAILQ_INSERT_TAIL(&b->b_qs[q], st, sync_list);
if (ref)
pf_ref_state(st);
}