Initial commit
This commit is contained in:
@@ -0,0 +1,102 @@
|
||||
From: Sara Sharon <sara.sharon@intel.com>
|
||||
Date: Wed, 29 Aug 2018 08:57:02 +0200
|
||||
Subject: [PATCH] mac80211: avoid kernel panic when building AMSDU from
|
||||
non-linear SKB
|
||||
|
||||
When building building AMSDU from non-linear SKB, we hit a
|
||||
kernel panic when trying to push the padding to the tail.
|
||||
Instead, put the padding at the head of the next subframe.
|
||||
This also fixes the A-MSDU subframes to not have the padding
|
||||
accounted in the length field and not have pad at all for
|
||||
the last subframe, both required by the spec.
|
||||
|
||||
Fixes: 6e0456b54545 ("mac80211: add A-MSDU tx support")
|
||||
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
|
||||
Reviewed-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
|
||||
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
|
||||
---
|
||||
|
||||
--- a/net/mac80211/tx.c
|
||||
+++ b/net/mac80211/tx.c
|
||||
@@ -3064,27 +3064,18 @@ void ieee80211_clear_fast_xmit(struct st
|
||||
}
|
||||
|
||||
static bool ieee80211_amsdu_realloc_pad(struct ieee80211_local *local,
|
||||
- struct sk_buff *skb, int headroom,
|
||||
- int *subframe_len)
|
||||
+ struct sk_buff *skb, int headroom)
|
||||
{
|
||||
- int amsdu_len = *subframe_len + sizeof(struct ethhdr);
|
||||
- int padding = (4 - amsdu_len) & 3;
|
||||
-
|
||||
- if (skb_headroom(skb) < headroom || skb_tailroom(skb) < padding) {
|
||||
+ if (skb_headroom(skb) < headroom) {
|
||||
I802_DEBUG_INC(local->tx_expand_skb_head);
|
||||
|
||||
- if (pskb_expand_head(skb, headroom, padding, GFP_ATOMIC)) {
|
||||
+ if (pskb_expand_head(skb, headroom, 0, GFP_ATOMIC)) {
|
||||
wiphy_debug(local->hw.wiphy,
|
||||
"failed to reallocate TX buffer\n");
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
- if (padding) {
|
||||
- *subframe_len += padding;
|
||||
- skb_put_zero(skb, padding);
|
||||
- }
|
||||
-
|
||||
return true;
|
||||
}
|
||||
|
||||
@@ -3108,8 +3099,7 @@ static bool ieee80211_amsdu_prepare_head
|
||||
if (info->control.flags & IEEE80211_TX_CTRL_AMSDU)
|
||||
return true;
|
||||
|
||||
- if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(*amsdu_hdr),
|
||||
- &subframe_len))
|
||||
+ if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(*amsdu_hdr)))
|
||||
return false;
|
||||
|
||||
data = skb_push(skb, sizeof(*amsdu_hdr));
|
||||
@@ -3176,7 +3166,8 @@ static bool ieee80211_amsdu_aggregate(st
|
||||
void *data;
|
||||
bool ret = false;
|
||||
unsigned int orig_len;
|
||||
- int n = 1, nfrags;
|
||||
+ int n = 1, nfrags, pad = 0;
|
||||
+ u16 hdrlen;
|
||||
|
||||
if (!ieee80211_hw_check(&local->hw, TX_AMSDU))
|
||||
return false;
|
||||
@@ -3228,8 +3219,19 @@ static bool ieee80211_amsdu_aggregate(st
|
||||
if (max_frags && nfrags > max_frags)
|
||||
goto out;
|
||||
|
||||
- if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(rfc1042_header) + 2,
|
||||
- &subframe_len))
|
||||
+ /*
|
||||
+ * Pad out the previous subframe to a multiple of 4 by adding the
|
||||
+ * padding to the next one, that's being added. Note that head->len
|
||||
+ * is the length of the full A-MSDU, but that works since each time
|
||||
+ * we add a new subframe we pad out the previous one to a multiple
|
||||
+ * of 4 and thus it no longer matters in the next round.
|
||||
+ */
|
||||
+ hdrlen = fast_tx->hdr_len - sizeof(rfc1042_header);
|
||||
+ if ((head->len - hdrlen) & 3)
|
||||
+ pad = 4 - ((head->len - hdrlen) & 3);
|
||||
+
|
||||
+ if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(rfc1042_header) +
|
||||
+ 2 + pad))
|
||||
goto out;
|
||||
|
||||
ret = true;
|
||||
@@ -3241,6 +3243,8 @@ static bool ieee80211_amsdu_aggregate(st
|
||||
memcpy(data, &len, 2);
|
||||
memcpy(data + 2, rfc1042_header, sizeof(rfc1042_header));
|
||||
|
||||
+ memset(skb_push(skb, pad), 0, pad);
|
||||
+
|
||||
head->len += skb->len;
|
||||
head->data_len += skb->len;
|
||||
*frag_tail = skb;
|
||||
Reference in New Issue
Block a user