diff options
| author | Jim Baxter <jim_baxter@mentor.com> | 2017-05-08 13:49:57 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-05-08 16:01:10 -0400 |
| commit | aeca3a77b1e0ed06a095933b89c86aed007383eb (patch) | |
| tree | 17c512c5adb4fa015607454c29a1c9095f508bfb | |
| parent | b210aeaedfc47ab8a86fbdcad46caf1e49cc0e37 (diff) | |
| download | linux-aeca3a77b1e0ed06a095933b89c86aed007383eb.tar.bz2 | |
net: cdc_ncm: Fix TX zero padding
The zero padding that is added to NTB's does
not zero the memory correctly.
This is because the skb_put modifies the value
of skb_out->len which results in the memset
command not setting any memory to zero as
(ctx->tx_max - skb_out->len) == 0.
I have resolved this by storing the size of
the memory to be zeroed before the skb_put
and using this in the memset call.
Signed-off-by: Jim Baxter <jim_baxter@mentor.com>
Reviewed-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/usb/cdc_ncm.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index bb3f71f9fbde..b5cec1824a78 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -1088,6 +1088,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign) u16 n = 0, index, ndplen; u8 ready2send = 0; u32 delayed_ndp_size; + size_t padding_count; /* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated * accordingly. Otherwise, we should check here. @@ -1244,11 +1245,13 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign) * a ZLP after full sized NTBs. */ if (!(dev->driver_info->flags & FLAG_SEND_ZLP) && - skb_out->len > ctx->min_tx_pkt) - memset(skb_put(skb_out, ctx->tx_max - skb_out->len), 0, - ctx->tx_max - skb_out->len); - else if (skb_out->len < ctx->tx_max && (skb_out->len % dev->maxpacket) == 0) + skb_out->len > ctx->min_tx_pkt) { + padding_count = ctx->tx_max - skb_out->len; + memset(skb_put(skb_out, padding_count), 0, padding_count); + } else if (skb_out->len < ctx->tx_max && + (skb_out->len % dev->maxpacket) == 0) { *skb_put(skb_out, 1) = 0; /* force short packet */ + } /* set final frame length */ nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data; |