From 77e73d1849c860d22ebba8826ad162ccfda4c535 Mon Sep 17 00:00:00 2001 From: Gertjan van Wingerde Date: Fri, 4 Dec 2009 23:47:01 +0100 Subject: [PATCH] rt2x00: Further L2 padding fixes. Fix a couple of more bugs in the L2 padding code: 1. Compute the amount of L2 padding correctly (in 3 places). 2. Trim the skb correctly when the L2 padding has been applied. Also introduce a central macro the compute the L2 padding size. Signed-off-by: Gertjan van Wingerde Acked-by: Ivo van Doorn Signed-off-by: John W. Linville --- drivers/net/wireless/rt2x00/rt2x00.h | 6 ++++++ drivers/net/wireless/rt2x00/rt2x00queue.c | 8 +++++--- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h index 4d841c0..194dae0 100644 --- a/drivers/net/wireless/rt2x00/rt2x00.h +++ b/drivers/net/wireless/rt2x00/rt2x00.h @@ -104,6 +104,12 @@ #define GET_DURATION_RES(__size, __rate)(((__size) * 8 * 10) % (__rate)) /* + * Determine the number of L2 padding bytes required between the header and + * the payload. + */ +#define L2PAD_SIZE(__hdrlen) (-(__hdrlen) & 3) + +/* * Determine the alignment requirement, * to make sure the 802.11 payload is padded to a 4-byte boundrary * we must determine the address of the payload and calculate the diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c index b8f0954..21d5876 100644 --- a/drivers/net/wireless/rt2x00/rt2x00queue.c +++ b/drivers/net/wireless/rt2x00/rt2x00queue.c @@ -181,7 +181,7 @@ void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int header_length) unsigned int frame_length = skb->len; unsigned int header_align = ALIGN_SIZE(skb, 0); unsigned int payload_align = ALIGN_SIZE(skb, header_length); - unsigned int l2pad = 4 - (payload_align - header_align); + unsigned int l2pad = L2PAD_SIZE(header_length); if (header_align == payload_align) { /* @@ -216,6 +216,7 @@ void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int header_length) memmove(skb->data + header_length + l2pad, skb->data + header_length + l2pad + payload_align, frame_length - header_length); + skb_trim(skb, frame_length + l2pad); skbdesc->flags |= SKBDESC_L2_PADDED; } } @@ -223,7 +224,7 @@ void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int header_length) void rt2x00queue_remove_l2pad(struct sk_buff *skb, unsigned int header_length) { struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb); - unsigned int l2pad = 4 - (header_length & 3); + unsigned int l2pad = L2PAD_SIZE(header_length); if (!l2pad || (skbdesc->flags & SKBDESC_L2_PADDED)) return; @@ -346,7 +347,8 @@ static void rt2x00queue_create_tx_descriptor(struct queue_entry *entry, * Header and alignment information. */ txdesc->header_length = ieee80211_get_hdrlen_from_skb(entry->skb); - txdesc->l2pad = ALIGN_SIZE(entry->skb, txdesc->header_length); + if (test_bit(DRIVER_REQUIRE_L2PAD, &rt2x00dev->flags)) + txdesc->l2pad = L2PAD_SIZE(txdesc->header_length); /* * Check whether this frame is to be acked. -- 2.7.4