The crypto(9) framework used by IPsec runs on a kernel task that

is protected by kernel lock.  There were crashes in swcr_authenc()
when it was accessing swcr_sessions.  As a quick fix, protect all
calls from network stack to crypto with kernel lock.  This also
covers the rekeying case that is called from pfkey via tdb_init().
OK mvs@

5 files changed, 64 insertions, 24 deletions

diff --git a/sys/netinet/ip_ah.c b/sys/netinet/ip_ah.c
index c4a450f49cf..c06dad5b72c 100644
--- a/sys/netinet/ip_ah.c
+++ b/sys/netinet/ip_ah.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_ah.c,v 1.146 2021/02/25 02:48:21 dlg Exp $ */
+/*	$OpenBSD: ip_ah.c,v 1.147 2021/06/18 15:34:21 bluhm Exp $ */
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -98,6 +98,7 @@ ah_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 {
 	struct auth_hash *thash = NULL;
 	struct cryptoini cria, crin;
+	int error;
 
 	/* Authentication operation. */
 	switch (ii->ii_authalg) {
@@ -162,7 +163,10 @@ ah_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 		cria.cri_next = &crin;
 	}
 
-	return crypto_newsession(&tdbp->tdb_cryptoid, &cria, 0);
+	KERNEL_LOCK();
+	error = crypto_newsession(&tdbp->tdb_cryptoid, &cria, 0);
+	KERNEL_UNLOCK();
+	return error;
 }
 
 /*
@@ -171,7 +175,7 @@ ah_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 int
 ah_zeroize(struct tdb *tdbp)
 {
-	int err;
+	int error;
 
 	if (tdbp->tdb_amxkey) {
 		explicit_bzero(tdbp->tdb_amxkey, tdbp->tdb_amxkeylen);
@@ -179,9 +183,11 @@ ah_zeroize(struct tdb *tdbp)
 		tdbp->tdb_amxkey = NULL;
 	}
 
-	err = crypto_freesession(tdbp->tdb_cryptoid);
+	KERNEL_LOCK();
+	error = crypto_freesession(tdbp->tdb_cryptoid);
+	KERNEL_UNLOCK();
 	tdbp->tdb_cryptoid = 0;
-	return err;
+	return error;
 }
 
 /*
@@ -696,7 +702,10 @@ ah_input(struct mbuf *m, struct tdb *tdb, int skip, int protoff)
 	tc->tc_rdomain = tdb->tdb_rdomain;
 	memcpy(&tc->tc_dst, &tdb->tdb_dst, sizeof(union sockaddr_union));
 
-	return crypto_dispatch(crp);
+	KERNEL_LOCK();
+	error = crypto_dispatch(crp);
+	KERNEL_UNLOCK();
+	return error;
 
  drop:
 	m_freem(m);
@@ -1144,7 +1153,10 @@ ah_output(struct mbuf *m, struct tdb *tdb, struct mbuf **mp, int skip,
 	tc->tc_rdomain = tdb->tdb_rdomain;
 	memcpy(&tc->tc_dst, &tdb->tdb_dst, sizeof(union sockaddr_union));
 
-	return crypto_dispatch(crp);
+	KERNEL_LOCK();
+	error = crypto_dispatch(crp);
+	KERNEL_UNLOCK();
+	return error;
 
  drop:
 	m_freem(m);
diff --git a/sys/netinet/ip_esp.c b/sys/netinet/ip_esp.c
index a74bfd341ac..40c3a0147b1 100644
--- a/sys/netinet/ip_esp.c
+++ b/sys/netinet/ip_esp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_esp.c,v 1.162 2021/02/25 02:48:21 dlg Exp $ */
+/*	$OpenBSD: ip_esp.c,v 1.163 2021/06/18 15:34:21 bluhm Exp $ */
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -93,6 +93,7 @@ esp_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 	struct enc_xform *txform = NULL;
 	struct auth_hash *thash = NULL;
 	struct cryptoini cria, crie, crin;
+	int error;
 
 	if (!ii->ii_encalg && !ii->ii_authalg) {
 		DPRINTF(("esp_init(): neither authentication nor encryption "
@@ -294,8 +295,11 @@ esp_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 		cria.cri_key = ii->ii_authkey;
 	}
 
-	return crypto_newsession(&tdbp->tdb_cryptoid,
+	KERNEL_LOCK();
+	error = crypto_newsession(&tdbp->tdb_cryptoid,
 	    (tdbp->tdb_encalgxform ? &crie : &cria), 0);
+	KERNEL_UNLOCK();
+	return error;
 }
 
 /*
@@ -304,7 +308,7 @@ esp_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 int
 esp_zeroize(struct tdb *tdbp)
 {
-	int err;
+	int error;
 
 	if (tdbp->tdb_amxkey) {
 		explicit_bzero(tdbp->tdb_amxkey, tdbp->tdb_amxkeylen);
@@ -318,9 +322,11 @@ esp_zeroize(struct tdb *tdbp)
 		tdbp->tdb_emxkey = NULL;
 	}
 
-	err = crypto_freesession(tdbp->tdb_cryptoid);
+	KERNEL_LOCK();
+	error = crypto_freesession(tdbp->tdb_cryptoid);
+	KERNEL_UNLOCK();
 	tdbp->tdb_cryptoid = 0;
-	return err;
+	return error;
 }
 
 #define MAXBUFSIZ (AH_ALEN_MAX > ESP_MAX_IVS ? AH_ALEN_MAX : ESP_MAX_IVS)
@@ -519,7 +525,10 @@ esp_input(struct mbuf *m, struct tdb *tdb, int skip, int protoff)
 			crde->crd_len = m->m_pkthdr.len - (skip + hlen + alen);
 	}
 
-	return crypto_dispatch(crp);
+	KERNEL_LOCK();
+	error = crypto_dispatch(crp);
+	KERNEL_UNLOCK();
+	return error;
 
  drop:
 	m_freem(m);
@@ -1006,7 +1015,10 @@ esp_output(struct mbuf *m, struct tdb *tdb, struct mbuf **mp, int skip,
 			crda->crd_len = m->m_pkthdr.len - (skip + alen);
 	}
 
-	return crypto_dispatch(crp);
+	KERNEL_LOCK();
+	error = crypto_dispatch(crp);
+	KERNEL_UNLOCK();
+	return error;
 
  drop:
 	m_freem(m);
diff --git a/sys/netinet/ip_ipcomp.c b/sys/netinet/ip_ipcomp.c
index 37bb95ea4b9..c93c34a4c96 100644
--- a/sys/netinet/ip_ipcomp.c
+++ b/sys/netinet/ip_ipcomp.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ip_ipcomp.c,v 1.67 2019/09/30 01:53:05 dlg Exp $ */
+/* $OpenBSD: ip_ipcomp.c,v 1.68 2021/06/18 15:34:21 bluhm Exp $ */
 
 /*
  * Copyright (c) 2001 Jean-Jacques Bernard-Gundol (jj@wabbitt.org)
@@ -79,6 +79,7 @@ ipcomp_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 {
 	struct comp_algo *tcomp = NULL;
 	struct cryptoini cric;
+	int error;
 
 	switch (ii->ii_compalg) {
 	case SADB_X_CALG_DEFLATE:
@@ -105,7 +106,10 @@ ipcomp_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 	memset(&cric, 0, sizeof(cric));
 	cric.cri_alg = tdbp->tdb_compalgxform->type;
 
-	return crypto_newsession(&tdbp->tdb_cryptoid, &cric, 0);
+	KERNEL_LOCK();
+	error = crypto_newsession(&tdbp->tdb_cryptoid, &cric, 0);
+	KERNEL_UNLOCK();
+	return error;
 }
 
 /*
@@ -114,11 +118,13 @@ ipcomp_init(struct tdb *tdbp, struct xformsw *xsp, struct ipsecinit *ii)
 int
 ipcomp_zeroize(struct tdb *tdbp)
 {
-	int err;
+	int error;
 
-	err = crypto_freesession(tdbp->tdb_cryptoid);
+	KERNEL_LOCK();
+	error = crypto_freesession(tdbp->tdb_cryptoid);
+	KERNEL_UNLOCK();
 	tdbp->tdb_cryptoid = 0;
-	return err;
+	return error;
 }
 
 /*
@@ -129,7 +135,7 @@ ipcomp_input(struct mbuf *m, struct tdb *tdb, int skip, int protoff)
 {
 	struct comp_algo *ipcompx = (struct comp_algo *) tdb->tdb_compalgxform;
 	struct tdb_crypto *tc;
-	int hlen;
+	int hlen, error;
 
 	struct cryptodesc *crdc = NULL;
 	struct cryptop *crp;
@@ -178,7 +184,10 @@ ipcomp_input(struct mbuf *m, struct tdb *tdb, int skip, int protoff)
 	tc->tc_rdomain = tdb->tdb_rdomain;
 	tc->tc_dst = tdb->tdb_dst;
 
-	return crypto_dispatch(crp);
+	KERNEL_LOCK();
+	error = crypto_dispatch(crp);
+	KERNEL_UNLOCK();
+	return error;
 }
 
 int
@@ -472,7 +481,10 @@ ipcomp_output(struct mbuf *m, struct tdb *tdb, struct mbuf **mp, int skip,
 	crp->crp_opaque = (caddr_t)tc;
 	crp->crp_sid = tdb->tdb_cryptoid;
 
-	return crypto_dispatch(crp);
+	KERNEL_LOCK();
+	error = crypto_dispatch(crp);
+	KERNEL_UNLOCK();
+	return error;
 
  drop:
 	m_freem(m);
diff --git a/sys/netinet/ipsec_input.c b/sys/netinet/ipsec_input.c
index 3b32d5373de..414830c4653 100644
--- a/sys/netinet/ipsec_input.c
+++ b/sys/netinet/ipsec_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ipsec_input.c,v 1.173 2020/09/01 01:53:34 gnezdo Exp $	*/
+/*	$OpenBSD: ipsec_input.c,v 1.174 2021/06/18 15:34:21 bluhm Exp $	*/
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -376,6 +376,8 @@ ipsec_input_cb(struct cryptop *crp)
 	struct tdb *tdb = NULL;
 	int clen, error;
 
+	KERNEL_ASSERT_LOCKED();
+
 	if (m == NULL) {
 		DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
 		ipsecstat_inc(ipsec_crypto);
diff --git a/sys/netinet/ipsec_output.c b/sys/netinet/ipsec_output.c
index 5e2b5d07e32..f72dba28944 100644
--- a/sys/netinet/ipsec_output.c
+++ b/sys/netinet/ipsec_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ipsec_output.c,v 1.79 2021/03/10 10:21:49 jsg Exp $ */
+/*	$OpenBSD: ipsec_output.c,v 1.80 2021/06/18 15:34:21 bluhm Exp $ */
 /*
  * The author of this code is Angelos D. Keromytis (angelos@cis.upenn.edu)
  *
@@ -391,6 +391,8 @@ ipsec_output_cb(struct cryptop *crp)
 	struct tdb *tdb = NULL;
 	int error, ilen, olen;
 
+	KERNEL_ASSERT_LOCKED();
+
 	if (m == NULL) {
 		DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
 		ipsecstat_inc(ipsec_crypto);