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| author | Eric Dumazet <eric.dumazet@gmail.com> | 2012-03-24 00:29:46 -0400 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2012-05-03 10:52:30 -0400 |
| commit | ed90542b0ce5415050c6fbfca324bccaafa69f2f (patch) | |
| tree | bc8426e780dd399259af2f8ba6e775b613714dc8 /drivers/net/wireless/iwlwifi/iwl-agn-rx.c | |
| parent | 9d1ceac5c6f7e77ea914de376ec17ced3eb22e5f (diff) | |
| download | blackbird-op-linux-ed90542b0ce5415050c6fbfca324bccaafa69f2f.tar.gz blackbird-op-linux-ed90542b0ce5415050c6fbfca324bccaafa69f2f.zip | |
iwlwifi: fix skb truesize underestimation
By default, iwlwifi uses order-1 pages (8 KB) to store incoming frames,
but doesnt say so in skb->truesize.
This makes very possible to exhaust kernel memory since these skb evade
normal socket memory accounting.
As struct ieee80211_hdr is going to be pulled before calling IP stack,
there is no need to use dev_alloc_skb() to reserve NET_SKB_PAD bytes.
alloc_skb() is ok in this driver, allowing more tailroom.
Pull beginning of frame in skb header, in the hope we can reuse order-1
pages in the driver immediately for small frames and reduce their
truesize to the minimum (linear skbs)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-agn-rx.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-agn-rx.c | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rx.c b/drivers/net/wireless/iwlwifi/iwl-agn-rx.c index f4b84d1596e3..22474608a70b 100644 --- a/drivers/net/wireless/iwlwifi/iwl-agn-rx.c +++ b/drivers/net/wireless/iwlwifi/iwl-agn-rx.c @@ -773,8 +773,7 @@ static void iwlagn_pass_packet_to_mac80211(struct iwl_priv *priv, struct sk_buff *skb; __le16 fc = hdr->frame_control; struct iwl_rxon_context *ctx; - struct page *p; - int offset; + unsigned int hdrlen, fraglen; /* We only process data packets if the interface is open */ if (unlikely(!priv->is_open)) { @@ -788,16 +787,24 @@ static void iwlagn_pass_packet_to_mac80211(struct iwl_priv *priv, iwlagn_set_decrypted_flag(priv, hdr, ampdu_status, stats)) return; - skb = dev_alloc_skb(128); + /* Dont use dev_alloc_skb(), we'll have enough headroom once + * ieee80211_hdr pulled. + */ + skb = alloc_skb(128, GFP_ATOMIC); if (!skb) { - IWL_ERR(priv, "dev_alloc_skb failed\n"); + IWL_ERR(priv, "alloc_skb failed\n"); return; } + hdrlen = min_t(unsigned int, len, skb_tailroom(skb)); + memcpy(skb_put(skb, hdrlen), hdr, hdrlen); + fraglen = len - hdrlen; - offset = (void *)hdr - rxb_addr(rxb); - p = rxb_steal_page(rxb); - skb_add_rx_frag(skb, 0, p, offset, len, len); + if (fraglen) { + int offset = (void *)hdr + hdrlen - rxb_addr(rxb); + skb_add_rx_frag(skb, 0, rxb_steal_page(rxb), offset, + fraglen, rxb->truesize); + } iwl_update_stats(priv, false, fc, len); /* |
