summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDaniel Borkmann <daniel@iogearbox.net>2018-06-20 00:33:54 +0300
committerDavid S. Miller <davem@davemloft.net>2018-06-20 01:24:28 +0300
commitc51818d5b793302b0923ade9856574ac28b9333b (patch)
tree06e0cd81581c6c4f0e64bb051b64cea9d454357a
parentd563e7a2ffd6275c195fe264e6cc8886eae877c5 (diff)
downloadlinux-c51818d5b793302b0923ade9856574ac28b9333b.tar.xz
bpf, xdp, i40e: fix i40e_build_skb skb reserve and truesize
Using skb_reserve(skb, I40E_SKB_PAD + (xdp->data - xdp->data_hard_start)) is clearly wrong since I40E_SKB_PAD already points to the offset where the original xdp->data was sitting since xdp->data_hard_start is defined as xdp->data - i40e_rx_offset(rx_ring) where latter offsets to I40E_SKB_PAD when build skb is used. However, also before cc5b114dcf98 ("bpf, i40e: add meta data support") this seems broken since bpf_xdp_adjust_head() helper could have been used to alter headroom and enlarge / shrink the frame and with that the assumption that the xdp->data remains unchanged does not hold and would push a bogus packet to upper stack. ixgbe got this right in 924708081629 ("ixgbe: add XDP support for pass and drop actions"). In any case, fix it by removing the I40E_SKB_PAD from both skb_reserve() and truesize calculation. Fixes: cc5b114dcf98 ("bpf, i40e: add meta data support") Fixes: 0c8493d90b6b ("i40e: add XDP support for pass and drop actions") Reported-by: Keith Busch <keith.busch@linux.intel.com> Reported-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: John Fastabend <john.fastabend@gmail.com> Tested-by: Keith Busch <keith.busch@linux.intel.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/net/ethernet/intel/i40e/i40e_txrx.c7
1 files changed, 3 insertions, 4 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 8ffb7454e67c..ed6dbcfd4e96 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2103,9 +2103,8 @@ static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring,
unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
#else
unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
- SKB_DATA_ALIGN(I40E_SKB_PAD +
- (xdp->data_end -
- xdp->data_hard_start));
+ SKB_DATA_ALIGN(xdp->data_end -
+ xdp->data_hard_start);
#endif
struct sk_buff *skb;
@@ -2124,7 +2123,7 @@ static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring,
return NULL;
/* update pointers within the skb to store the data */
- skb_reserve(skb, I40E_SKB_PAD + (xdp->data - xdp->data_hard_start));
+ skb_reserve(skb, xdp->data - xdp->data_hard_start);
__skb_put(skb, xdp->data_end - xdp->data);
if (metasize)
skb_metadata_set(skb, metasize);