[PATCH V1 0/1] net: cdc_ncm: Fix TX zero padding

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Analysis
--------

The zero padding that is added to NTB's does not zero
the memory correctly.
This happens because the skb_put called within the memset in
the line:
memset(skb_put(skb_out, ctx->tx_max - skb_out->len),
       0, ctx->tx_max - skb_out->len);
causes the value of skb_out->len to be modified during
the two uses of it within the above line.
This causes non-zeroed data at the end of skb_out.

This issue was found when connecting between an ARM
Sabre SD Host platform and a test box that was
dropping the NDP's due to the non zeroed memory being
identified as an error.

Solution
--------

To resolve this I have cached the value of
ctx->tx_max - skb_out->len before the memset operation.

Jim Baxter (1):
  net: cdc_ncm: Fix TX zero padding

 drivers/net/usb/cdc_ncm.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux