The NDP was ignoring the wNextNdpIndex in the NDP which
means that NTBs containing multiple NDPs would have missed
frames.
Signed-off-by: Jim Baxter <jim_baxter@xxxxxxxxxx>
---
This patch originally came about because I read the CDC-NCM specification
Figures 3-1, 3-2 and table 3-4 which specifies 32bit NDPs as a link.
It has since been noted that table 3-3 states it is reserved so there is
an inconsistancy in the specfification which this patch covers either
version of.
drivers/usb/gadget/f_ncm.c | 146 +++++++++++++++++++++++---------------------
1 file changed, 78 insertions(+), 68 deletions(-)
diff --git a/drivers/usb/gadget/f_ncm.c b/drivers/usb/gadget/f_ncm.c
index a9499fd..d0ebbac 100644
--- a/drivers/usb/gadget/f_ncm.c
+++ b/drivers/usb/gadget/f_ncm.c
@@ -963,6 +963,7 @@ static int ncm_unwrap_ntb(struct gether *port,
struct f_ncm *ncm = func_to_ncm(&port->func);
__le16 *tmp = (void *) skb->data;
unsigned index, index2;
+ int ndp_index;
unsigned dg_len, dg_len2;
unsigned ndp_len;
struct sk_buff *skb2;
@@ -995,91 +996,100 @@ static int ncm_unwrap_ntb(struct gether *port,
goto err;
}
- index = get_ncm(&tmp, opts->fp_index);
- /* NCM 3.2 */
- if (((index % 4) != 0) && (index < opts->nth_size)) {
- INFO(port->func.config->cdev, "Bad index: %x\n",
- index);
- goto err;
- }
-
- /* walk through NDP */
- tmp = ((void *)skb->data) + index;
- if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
- INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
- goto err;
- }
- tmp += 2;
-
- ndp_len = get_unaligned_le16(tmp++);
- /*
- * NCM 3.3.1
- * entry is 2 items
- * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
- * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
- */
- if ((ndp_len < opts->ndp_size + 2 * 2 * (opts->dgram_item_len * 2))
- || (ndp_len % opts->ndplen_align != 0)) {
- INFO(port->func.config->cdev, "Bad NDP length: %x\n", ndp_len);
- goto err;
- }
- tmp += opts->reserved1;
- tmp += opts->next_fp_index; /* skip reserved (d)wNextFpIndex */
- tmp += opts->reserved2;
-
- ndp_len -= opts->ndp_size;
- index2 = get_ncm(&tmp, opts->dgram_item_len);
- dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
- dgram_counter = 0;
+ ndp_index = get_ncm(&tmp, opts->fp_index);
+ /* Run through all the NDP's in the NTB */
do {
- index = index2;
- dg_len = dg_len2;
- if (dg_len < 14 + crc_len) { /* ethernet header + crc */
- INFO(port->func.config->cdev, "Bad dgram length: %x\n",
- dg_len);
+ /* NCM 3.2 */
+ if (((ndp_index % 4) != 0) &&
+ (ndp_index < opts->nth_size)) {
+ INFO(port->func.config->cdev, "Bad index: %#X\n",
+ ndp_index);
goto err;
}
- if (ncm->is_crc) {
- uint32_t crc, crc2;
-
- crc = get_unaligned_le32(skb->data +
- index + dg_len - crc_len);
- crc2 = ~crc32_le(~0,
- skb->data + index,
- dg_len - crc_len);
- if (crc != crc2) {
- INFO(port->func.config->cdev, "Bad CRC\n");
- goto err;
- }
+
+ /* walk through NDP */
+ tmp = (void *)(skb->data + ndp_index);
+ if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
+ INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
+ goto err;
}
+ tmp += 2;
+ ndp_len = get_unaligned_le16(tmp++);
+ /*
+ * NCM 3.3.1
+ * entry is 2 items
+ * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
+ * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
+ * Each entry is a dgram index and a dgram length.
+ */
+ if ((ndp_len < opts->ndp_size
+ + 2 * 2 * (opts->dgram_item_len * 2))
+ || (ndp_len % opts->ndplen_align != 0)) {
+ INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
+ ndp_len);
+ goto err;
+ }
+ tmp += opts->reserved1;
+ /* Check for another NDP (d)wNextNdpIndex */
+ ndp_index = get_ncm(&tmp, opts->next_fp_index);
+ tmp += opts->reserved2;
+
+ ndp_len -= opts->ndp_size;
index2 = get_ncm(&tmp, opts->dgram_item_len);
dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
+ dgram_counter = 0;
+
+ do {
+ index = index2;
+ dg_len = dg_len2;
+ if (dg_len < 14 + crc_len) { /* ethernet hdr + crc */
+ INFO(port->func.config->cdev,
+ "Bad dgram length: %#X\n", dg_len);
+ goto err;
+ }
+ if (ncm->is_crc) {
+ uint32_t crc, crc2;
+
+ crc = get_unaligned_le32(skb->data +
+ index + dg_len -
+ crc_len);
+ crc2 = ~crc32_le(~0,
+ skb->data + index,
+ dg_len - crc_len);
+ if (crc != crc2) {
+ INFO(port->func.config->cdev,
+ "Bad CRC\n");
+ goto err;
+ }
+ }
+
+ index2 = get_ncm(&tmp, opts->dgram_item_len);
+ dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
- if (index2 == 0 || dg_len2 == 0) {
- skb2 = skb;
- } else {
skb2 = skb_clone(skb, GFP_ATOMIC);
if (skb2 == NULL)
goto err;
- }
- if (!skb_pull(skb2, index)) {
- ret = -EOVERFLOW;
- goto err;
- }
+ if (!skb_pull(skb2, index)) {
+ ret = -EOVERFLOW;
+ goto err;
+ }
- skb_trim(skb2, dg_len - crc_len);
- skb_queue_tail(list, skb2);
+ skb_trim(skb2, dg_len - crc_len);
+ skb_queue_tail(list, skb2);
- ndp_len -= 2 * (opts->dgram_item_len * 2);
+ ndp_len -= 2 * (opts->dgram_item_len * 2);
- dgram_counter++;
+ dgram_counter++;
- if (index2 == 0 || dg_len2 == 0)
- break;
- } while (ndp_len > 2 * (opts->dgram_item_len * 2)); /* zero entry */
+ if (index2 == 0 || dg_len2 == 0)
+ break;
+ } while (ndp_len > 2 * (opts->dgram_item_len * 2));
+ } while (ndp_index);
+
+ dev_kfree_skb_any(skb);
VDBG(port->func.config->cdev,
"Parsed NTB with %d frames\n", dgram_counter);
--
1.7.9.5
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