This is a note to let you know that I've just added the patch titled batman-adv: fix TT CRC computation by ensuring byte order to the 3.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: batman-adv-fix-tt-crc-computation-by-ensuring-byte-order.patch and it can be found in the queue-3.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Feb 27 20:11:26 PST 2014 From: Antonio Quartulli <antonio@xxxxxxxxxxxxx> Date: Tue, 11 Feb 2014 17:05:06 +0100 Subject: batman-adv: fix TT CRC computation by ensuring byte order From: Antonio Quartulli <antonio@xxxxxxxxxxxxx> [ Upstream commit a30e22ca8464c2dc573e0144a972221c2f06c2cd ] When computing the CRC on a 2byte variable the order of the bytes obviously alters the final result. This means that computing the CRC over the same value on two archs having different endianess leads to different numbers. The global and local translation table CRC computation routine makes this mistake while processing the clients VIDs. The result is a continuous CRC mismatching between nodes having different endianess. Fix this by converting the VID to Network Order before processing it. This guarantees that every node uses the same byte order. Introduced by 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b ("batman-adv: make the TT CRC logic VLAN specific") Reported-by: Russel Senior <russell@xxxxxxxxxxxxxxxxx> Signed-off-by: Antonio Quartulli <antonio@xxxxxxxxxxxxx> Tested-by: Russell Senior <russell@xxxxxxxxxxxxxxxxx> Signed-off-by: Marek Lindner <mareklindner@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/batman-adv/translation-table.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -1961,6 +1961,7 @@ static uint32_t batadv_tt_global_crc(str struct hlist_head *head; uint32_t i, crc_tmp, crc = 0; uint8_t flags; + __be16 tmp_vid; for (i = 0; i < hash->size; i++) { head = &hash->table[i]; @@ -1997,8 +1998,11 @@ static uint32_t batadv_tt_global_crc(str orig_node)) continue; - crc_tmp = crc32c(0, &tt_common->vid, - sizeof(tt_common->vid)); + /* use network order to read the VID: this ensures that + * every node reads the bytes in the same order. + */ + tmp_vid = htons(tt_common->vid); + crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid)); /* compute the CRC on flags that have to be kept in sync * among nodes @@ -2032,6 +2036,7 @@ static uint32_t batadv_tt_local_crc(stru struct hlist_head *head; uint32_t i, crc_tmp, crc = 0; uint8_t flags; + __be16 tmp_vid; for (i = 0; i < hash->size; i++) { head = &hash->table[i]; @@ -2050,8 +2055,11 @@ static uint32_t batadv_tt_local_crc(stru if (tt_common->flags & BATADV_TT_CLIENT_NEW) continue; - crc_tmp = crc32c(0, &tt_common->vid, - sizeof(tt_common->vid)); + /* use network order to read the VID: this ensures that + * every node reads the bytes in the same order. + */ + tmp_vid = htons(tt_common->vid); + crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid)); /* compute the CRC on flags that have to be kept in sync * among nodes Patches currently in stable-queue which might be from antonio@xxxxxxxxxxxxx are queue-3.13/batman-adv-avoid-potential-race-condition-when-adding-a-new-neighbour.patch queue-3.13/batman-adv-fix-tt-crc-computation-by-ensuring-byte-order.patch queue-3.13/batman-adv-free-skb-on-tvlv-parsing-success.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html