@@ -893,16 +893,18 @@ static void r6040_multicast_list(struct net_device *dev)
/* Multicast Address 1~4 case */
i = 0;
netdev_for_each_mc_addr(ha, dev) {
- if (i < MCAST_MAX) {
- adrp = (u16 *) ha->addr;
- iowrite16(adrp[0], ioaddr + MID_1L + 8 * i);
- iowrite16(adrp[1], ioaddr + MID_1M + 8 * i);
- iowrite16(adrp[2], ioaddr + MID_1H + 8 * i);
- } else {
- iowrite16(0xffff, ioaddr + MID_1L + 8 * i);
- iowrite16(0xffff, ioaddr + MID_1M + 8 * i);
- iowrite16(0xffff, ioaddr + MID_1H + 8 * i);
- }
+ if (i >= MCAST_MAX)
+ break;
+ adrp = (u16 *) ha->addr;
+ iowrite16(adrp[0], ioaddr + MID_1L + 8 * i);
+ iowrite16(adrp[1], ioaddr + MID_1M + 8 * i);
+ iowrite16(adrp[2], ioaddr + MID_1H + 8 * i);
+ i++;
+ }
+ while (i < MCAST_MAX) {
+ iowrite16(0xffff, ioaddr + MID_1L + 8 * i);
+ iowrite16(0xffff, ioaddr + MID_1M + 8 * i);
+ iowrite16(0xffff, ioaddr + MID_1H + 8 * i);
i++;
}
}
This code has been broken forever, but in several different and creative ways. So far as I can work out, the R6040 MAC filter has 4 exact-match entries, the first of which the driver uses for its assigned unicast address, plus a 64-entry hash-based filter for multicast addresses (maybe unicast as well?). The original version of this code would write the first 4 multicast addresses as exact-match entries from offset 1 (bug #1: there is no entry 4 so this could write to some PHY registers). It would fill the remainder of the exact-match entries with the broadcast address (bug #2: this would overwrite the last used entry). If more than 4 multicast addresses were configured, it would set up the hash table, write some random crap to the MAC control register (bug #3) and finally walk off the end of the list when filling the exact-match entries (bug #4). All of this seems to be pointless, since it sets the promiscuous bit when the interface is made promiscuous or if >4 multicast addresses are enabled, and never clears it (bug #5, masking bug #2). The recent(ish) changes to the multicast list fixed bug #4, but completely removed the limit on iteration over the exact-match entries (bug #6). Bug #4 was reported as <https://bugzilla.kernel.org/show_bug.cgi?id=15355> and more recently as <http://bugs.debian.org/600155>. Florian Fainelli attempted to fix these in commit 3bcf8229a8c49769e48d3e0bd1e20d8e003f8106, but that actually dealt with bugs #1-3, bug #4 having been fixed in mainline at that point. That commit fixes the most important current bug #6. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: stable@kernel.org [2.6.35 only] --- Commit message was slightly mangled in the previous message. Ben. drivers/net/r6040.c | 22 ++++++++++++---------- 1 files changed, 12 insertions(+), 10 deletions(-)