epair(4): make sure we do not duplicate MAC addresses
in case of reused if_index. PR: 229957 Tested by: O. Hartmann <ohartmann@walstatt.org> Approved by: avg (mentor)
This commit is contained in:
parent
afe7cf8749
commit
804771f553
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=336628
@ -107,6 +107,7 @@ static int epair_clone_create(struct if_clone *, char *, size_t, caddr_t);
|
||||
static int epair_clone_destroy(struct if_clone *, struct ifnet *);
|
||||
|
||||
static const char epairname[] = "epair";
|
||||
static unsigned int next_index = 0;
|
||||
|
||||
/* Netisr related definitions and sysctl. */
|
||||
static struct netisr_handler epair_nh = {
|
||||
@ -843,12 +844,22 @@ epair_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
|
||||
|
||||
/*
|
||||
* Calculate the etheraddr hashing the hostid and the
|
||||
* interface index. The result would be hopefully unique
|
||||
* interface index. The result would be hopefully unique.
|
||||
* Note that the "a" component of an epair instance may get moved
|
||||
* to a different VNET after creation. In that case its index
|
||||
* will be freed and the index can get reused by new epair instance.
|
||||
* Make sure we do not create same etheraddr again.
|
||||
*/
|
||||
getcredhostid(curthread->td_ucred, (unsigned long *)&hostid);
|
||||
if (hostid == 0)
|
||||
arc4rand(&hostid, sizeof(hostid), 0);
|
||||
key[0] = (uint32_t)ifp->if_index;
|
||||
|
||||
if (ifp->if_index > next_index)
|
||||
next_index = ifp->if_index;
|
||||
else
|
||||
next_index++;
|
||||
|
||||
key[0] = (uint32_t)next_index;
|
||||
key[1] = (uint32_t)(hostid & 0xffffffff);
|
||||
key[2] = (uint32_t)((hostid >> 32) & 0xfffffffff);
|
||||
hash = jenkins_hash32(key, 3, 0);
|
||||
|
Loading…
Reference in New Issue
Block a user