This is a note to let you know that I've just added the patch titled
net: cdc_ncm: Fix TX zero padding
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-cdc_ncm-fix-tx-zero-padding.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Apr 10 10:31:53 CEST 2018
From: Jim Baxter <jim_baxter@xxxxxxxxxx>
Date: Mon, 8 May 2017 13:49:57 +0100
Subject: net: cdc_ncm: Fix TX zero padding
From: Jim Baxter <jim_baxter@xxxxxxxxxx>
[ Upstream commit aeca3a77b1e0ed06a095933b89c86aed007383eb ]
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@xxxxxxxxxx>
Reviewed-by: Bjørn Mork <bjorn@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/usb/cdc_ncm.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -1069,6 +1069,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev
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.
@@ -1225,11 +1226,13 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev
* 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;
Patches currently in stable-queue which might be from jim_baxter@xxxxxxxxxx are
queue-4.4/net-cdc_ncm-fix-tx-zero-padding.patch