git: bd7b2f95019e - main - vnet: (read) lock the vnet list while iterating it

[Kristof Provost]

The branch main has been updated by kp:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=bd7b2f95019e9715150c34736279805de0818d09

commit bd7b2f95019e9715150c34736279805de0818d09
Author:     Kristof Provost <k...@freebsd.org>
AuthorDate: 2023-12-05 19:08:11 +0000
Commit:     Kristof Provost <k...@freebsd.org>
CommitDate: 2023-12-07 12:34:47 +0000

    vnet: (read) lock the vnet list while iterating it
    
    Ensure that the vnet list cannot be modified while we're running through
    it.
    
    Reviewed by:    mjg (previous version), zlei (previous version)
    MFC after:      1 week
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    Differential Revision:  https://reviews.freebsd.org/D42927
---
 sys/net/vnet.c         | 4 ++++
 sys/netinet/ip_reass.c | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/sys/net/vnet.c b/sys/net/vnet.c
index ac937125a19d..9668471633f4 100644
--- a/sys/net/vnet.c
+++ b/sys/net/vnet.c
@@ -536,11 +536,13 @@ vnet_register_sysinit(void *arg)
         * Invoke the constructor on all the existing vnets when it is
         * registered.
         */
+       VNET_LIST_RLOCK();
        VNET_FOREACH(vnet) {
                CURVNET_SET_QUIET(vnet);
                vs->func(vs->arg);
                CURVNET_RESTORE();
        }
+       VNET_LIST_RUNLOCK();
        VNET_SYSINIT_WUNLOCK();
 }
 
@@ -592,6 +594,7 @@ vnet_deregister_sysuninit(void *arg)
         * deregistered.
         */
        VNET_SYSINIT_WLOCK();
+       VNET_LIST_RLOCK();
        VNET_FOREACH(vnet) {
                CURVNET_SET_QUIET(vnet);
                vs->func(vs->arg);
@@ -601,6 +604,7 @@ vnet_deregister_sysuninit(void *arg)
        /* Remove the destructor from the global list of vnet destructors. */
        TAILQ_REMOVE(&vnet_destructors, vs, link);
        VNET_SYSINIT_WUNLOCK();
+       VNET_LIST_RUNLOCK();
 }
 
 /*
diff --git a/sys/netinet/ip_reass.c b/sys/netinet/ip_reass.c
index 219a869c5139..a95780aa2f27 100644
--- a/sys/netinet/ip_reass.c
+++ b/sys/netinet/ip_reass.c
@@ -661,11 +661,13 @@ ipreass_drain(void)
 {
        VNET_ITERATOR_DECL(vnet_iter);
 
+       VNET_LIST_RLOCK();
        VNET_FOREACH(vnet_iter) {
                CURVNET_SET(vnet_iter);
                ipreass_drain_vnet();
                CURVNET_RESTORE();
        }
+       VNET_LIST_RUNLOCK();
 }