The branch stable/13 has been updated by tuexen:
URL:
https://cgit.FreeBSD.org/src/commit/?id=331db93815afb49b01f269aeff0fe899acd47455
commit 331db93815afb49b01f269aeff0fe899acd47455
Author: Michael Tuexen <tue...@freebsd.org>
AuthorDate: 2024-11-03 09:20:08 +0000
Commit: Michael Tuexen <tue...@freebsd.org>
CommitDate: 2024-11-06 12:33:58 +0000
sctp: improve handling of address changes
Identify interfaces consistenly by the pair of the ifn pointer
and the index.
This avoids a use after free when the ifn and or index was reused.
Reported by: bz, pho, and others
(cherry picked from commit 523913c94371ab50a8129cbab820394d25f7a269)
---
sys/netinet/sctp_bsd_addr.c | 1 +
sys/netinet/sctp_pcb.c | 23 +++++++++++++----------
sys/netinet/sctp_pcb.h | 2 +-
3 files changed, 15 insertions(+), 11 deletions(-)
diff --git a/sys/netinet/sctp_bsd_addr.c b/sys/netinet/sctp_bsd_addr.c
index d190be1948ba..5381898ab0ef 100644
--- a/sys/netinet/sctp_bsd_addr.c
+++ b/sys/netinet/sctp_bsd_addr.c
@@ -338,6 +338,7 @@ sctp_addr_change(struct ifaddr *ifa, int cmd)
(void *)ifa, ifa->ifa_addr, ifa_flags, 1);
} else {
sctp_del_addr_from_vrf(SCTP_DEFAULT_VRFID, ifa->ifa_addr,
+ (void *)ifa->ifa_ifp,
ifa->ifa_ifp->if_index);
/*
diff --git a/sys/netinet/sctp_pcb.c b/sys/netinet/sctp_pcb.c
index 469c401978ac..0ad898c6df69 100644
--- a/sys/netinet/sctp_pcb.c
+++ b/sys/netinet/sctp_pcb.c
@@ -193,12 +193,11 @@ sctp_find_ifn(void *ifn, uint32_t ifn_index)
struct sctp_ifnlist *hash_ifn_head;
SCTP_IPI_ADDR_LOCK_ASSERT();
+ KASSERT(ifn != NULL, ("sctp_find_ifn(NULL, %u) called", ifn_index));
hash_ifn_head = &SCTP_BASE_INFO(vrf_ifn_hash)[(ifn_index &
SCTP_BASE_INFO(vrf_ifn_hashmark))];
LIST_FOREACH(sctp_ifnp, hash_ifn_head, next_bucket) {
- if (sctp_ifnp->ifn_index == ifn_index) {
- break;
- }
- if (ifn != NULL && sctp_ifnp->ifn_p == ifn) {
+ if (sctp_ifnp->ifn_index == ifn_index &&
+ sctp_ifnp->ifn_p == ifn) {
break;
}
}
@@ -439,7 +438,8 @@ sctp_add_addr_to_vrf(uint32_t vrf_id, void *ifn, uint32_t
ifn_index,
if (sctp_ifap != NULL) {
/* The address being added is already or still known. */
if (sctp_ifap->ifn_p != NULL) {
- if (sctp_ifap->ifn_p->ifn_index == ifn_index) {
+ if (sctp_ifap->ifn_p->ifn_index == ifn_index &&
+ sctp_ifap->ifn_p->ifn_p == ifn) {
SCTPDBG(SCTP_DEBUG_PCB4,
"Using existing ifn %s (0x%x) for ifa %p\n",
sctp_ifap->ifn_p->ifn_name, ifn_index,
@@ -578,7 +578,7 @@ sctp_add_addr_to_vrf(uint32_t vrf_id, void *ifn, uint32_t
ifn_index,
*/
SCTPDBG(SCTP_DEBUG_PCB4, "Lost an address change?\n");
/* Opps, must decrement the count */
- sctp_del_addr_from_vrf(vrf_id, addr, ifn_index);
+ sctp_del_addr_from_vrf(vrf_id, addr, ifn, ifn_index);
return (NULL);
}
SCTP_INCR_LADDR_COUNT();
@@ -603,7 +603,7 @@ sctp_add_addr_to_vrf(uint32_t vrf_id, void *ifn, uint32_t
ifn_index,
void
sctp_del_addr_from_vrf(uint32_t vrf_id, struct sockaddr *addr,
- uint32_t ifn_index)
+ void *ifn, uint32_t ifn_index)
{
struct sctp_vrf *vrf;
struct sctp_ifa *sctp_ifap;
@@ -624,9 +624,12 @@ sctp_del_addr_from_vrf(uint32_t vrf_id, struct sockaddr
*addr,
if (sctp_ifap != NULL) {
/* Validate the delete */
if (sctp_ifap->ifn_p) {
- if (ifn_index != sctp_ifap->ifn_p->ifn_index) {
- SCTPDBG(SCTP_DEBUG_PCB4, "ifn:%d ifname:%s -
ignoring delete\n",
- sctp_ifap->ifn_p->ifn_index,
sctp_ifap->ifn_p->ifn_name);
+ if (ifn_index != sctp_ifap->ifn_p->ifn_index ||
+ ifn != sctp_ifap->ifn_p->ifn_p) {
+ SCTPDBG(SCTP_DEBUG_PCB4, "ifn:%d (p) ifname:%s
- ignoring delete\n",
+ sctp_ifap->ifn_p->ifn_index,
+ sctp_ifap->ifn_p->ifn_p,
+ sctp_ifap->ifn_p->ifn_name);
SCTP_IPI_ADDR_WUNLOCK();
return;
}
diff --git a/sys/netinet/sctp_pcb.h b/sys/netinet/sctp_pcb.h
index 7ef6feee9c01..ce38e7cede2d 100644
--- a/sys/netinet/sctp_pcb.h
+++ b/sys/netinet/sctp_pcb.h
@@ -497,7 +497,7 @@ void sctp_free_ifa(struct sctp_ifa *sctp_ifap);
void
sctp_del_addr_from_vrf(uint32_t vrfid, struct sockaddr *addr,
- uint32_t ifn_index);
+ void *ifn, uint32_t ifn_index);
struct sctp_nets *sctp_findnet(struct sctp_tcb *, struct sockaddr *);
