[Bug 200323] BPF userland misuse can crash the system

[bugzilla-noreply at freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=200323

--- Comment #1 from Ermal Luçi <eri at pfsense.org> ---
This patch fixes the issue and the issue seems to a locked LLE which does not
allow BPF to sleep when it needs to.

+diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
+index baa9c26..f31576d 100644
+--- a/sys/netinet/if_ether.c
++++ b/sys/netinet/if_ether.c
+@@ -353,6 +353,10 @@ retry:
+     if ((la->la_flags & LLE_VALID) &&
+         ((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime)) {
+         bcopy(&la->ll_addr, desten, ifp->if_addrlen);
++        if (flags & LLE_EXCLUSIVE)
++            LLE_WUNLOCK(la);
++        else
++            LLE_RUNLOCK(la);
+         /*
+          * If entry has an expiry time and it is approaching,
+          * see if we need to send an ARP request within this
+@@ -365,8 +369,7 @@ retry:
+         }
+ 
+         *lle = la;
+-        error = 0;
+-        goto done;
++        return (0);
+     }
+ 
+     if (la->la_flags & LLE_STATIC) {   /* should not happen! */

-- 
You are receiving this mail because:
You are the assignee for the bug.