The branch main has been updated by mjg:
URL:
https://cgit.FreeBSD.org/src/commit/?id=f5a365e51feea75d1e5ebc86c53808d8cae7b6d7
commit f5a365e51feea75d1e5ebc86c53808d8cae7b6d7
Author: Mateusz Guzik <m...@freebsd.org>
AuthorDate: 2023-03-29 12:46:41 +0000
Commit: Mateusz Guzik <m...@freebsd.org>
CommitDate: 2023-03-30 08:46:38 +0000
inet6: protect address manipulation with a lock
This is a total hack/bare minimum which follows inet4.
Otherwise 2 threads removing the same address can easily crash.
Reviewed by: kp
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D39317
---
sys/netinet6/in6.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 27dc3550177c..3d967e9a40c7 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -168,6 +168,9 @@ static void in6_leave_proxy_ndp_mc(struct ifnet *, const
struct in6_addr *);
#define ifa2ia6(ifa) ((struct in6_ifaddr *)(ifa))
#define ia62ifa(ia6) (&((ia6)->ia_ifa))
+static struct sx in6_control_sx;
+SX_SYSINIT(in6_control_sx, &in6_control_sx, "in6_control");
+
void
in6_newaddrmsg(struct in6_ifaddr *ia, int cmd)
{
@@ -254,6 +257,7 @@ in6_control(struct socket *so, u_long cmd, void *data,
struct in6_aliasreq *ifra = (struct in6_aliasreq *)data;
struct sockaddr_in6 *sa6;
int error;
+ bool control_locked = false;
/*
* Compat to make pre-10.x ifconfig(8) operable.
@@ -411,6 +415,8 @@ in6_control(struct socket *so, u_long cmd, void *data,
if (td != NULL && (error = prison_check_ip6(td->td_ucred,
&sa6->sin6_addr)) != 0)
return (error);
+ sx_xlock(&in6_control_sx);
+ control_locked = true;
ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
} else
ia = NULL;
@@ -582,6 +588,9 @@ in6_control(struct socket *so, u_long cmd, void *data,
error = 0;
out:
+ if (control_locked)
+ sx_xunlock(&in6_control_sx);
+
if (ia != NULL)
ifa_free(&ia->ia_ifa);
return (error);
