Messages in this thread Patch in this message | | | Date | Fri, 19 Nov 2010 13:56:28 -0800 | From | Greg KH <> | Subject | [67/82] r6040: Fix multicast filter some more |
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2.6.35-stable review patch. If anyone has any objections, please let us know.
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From: Ben Hutchings <ben@decadent.org.uk>
[ Upstream commit e2269308359d5863b6aa1fcb95a425a2ab255f1f ]
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> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> --- drivers/net/r6040.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-)
--- a/drivers/net/r6040.c +++ b/drivers/net/r6040.c @@ -988,16 +988,18 @@ static void r6040_multicast_list(struct /* 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++; } }
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