From: Alexey Orishko Date: Wed, 14 Mar 2012 11:26:12 +0000 (+0000) Subject: cdc_ncm: avoid discarding datagrams in rx path X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d5ddb4a59ed43b4c569b4efa8b508d50ef140cc6;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git cdc_ncm: avoid discarding datagrams in rx path Changes: - removed a limit for amount of datagrams for IN NTB - using pointer to traverse NTB in rx_fixup() - renamed "temp" to "len" in rx_fixup() - do NTB sequence number check in rx path Tested on Intel/ARM. Reviewed-by: Sjur Brændeland Tested-by: Dmitry Tarnyagin Signed-off-by: Alexey Orishko Signed-off-by: David S. Miller --- diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index f8f194658412..7adc9f6b0ea1 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -71,13 +71,10 @@ /* * Maximum amount of datagrams in NCM Datagram Pointer Table, not counting - * the last NULL entry. Any additional datagrams in NTB would be discarded. + * the last NULL entry. */ #define CDC_NCM_DPT_DATAGRAMS_MAX 40 -/* Maximum amount of IN datagrams in NTB */ -#define CDC_NCM_DPT_DATAGRAMS_IN_MAX 0 /* unlimited */ - /* Restart the timer, if amount of datagrams is less than given value */ #define CDC_NCM_RESTART_TIMER_DATAGRAM_CNT 3 #define CDC_NCM_TIMER_PENDING_CNT 2 @@ -95,7 +92,6 @@ struct cdc_ncm_data { }; struct cdc_ncm_ctx { - struct cdc_ncm_data rx_ncm; struct cdc_ncm_data tx_ncm; struct usb_cdc_ncm_ntb_parameters ncm_parm; struct hrtimer tx_timer; @@ -135,6 +131,7 @@ struct cdc_ncm_ctx { u16 tx_modulus; u16 tx_ndp_modulus; u16 tx_seq; + u16 rx_seq; u16 connected; }; @@ -956,108 +953,103 @@ error: static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in) { struct sk_buff *skb; - struct cdc_ncm_ctx *ctx; - int sumlen; - int actlen; - int temp; + struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; + int len; int nframes; int x; int offset; + struct usb_cdc_ncm_nth16 *nth16; + struct usb_cdc_ncm_ndp16 *ndp16; + struct usb_cdc_ncm_dpe16 *dpe16; - ctx = (struct cdc_ncm_ctx *)dev->data[0]; if (ctx == NULL) goto error; - actlen = skb_in->len; - sumlen = CDC_NCM_NTB_MAX_SIZE_RX; - - if (actlen < (sizeof(ctx->rx_ncm.nth16) + sizeof(ctx->rx_ncm.ndp16))) { + if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) + + sizeof(struct usb_cdc_ncm_ndp16))) { pr_debug("frame too short\n"); goto error; } - memcpy(&(ctx->rx_ncm.nth16), ((u8 *)skb_in->data), - sizeof(ctx->rx_ncm.nth16)); + nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data; - if (le32_to_cpu(ctx->rx_ncm.nth16.dwSignature) != - USB_CDC_NCM_NTH16_SIGN) { + if (le32_to_cpu(nth16->dwSignature) != USB_CDC_NCM_NTH16_SIGN) { pr_debug("invalid NTH16 signature <%u>\n", - le32_to_cpu(ctx->rx_ncm.nth16.dwSignature)); + le32_to_cpu(nth16->dwSignature)); goto error; } - temp = le16_to_cpu(ctx->rx_ncm.nth16.wBlockLength); - if (temp > sumlen) { - pr_debug("unsupported NTB block length %u/%u\n", temp, sumlen); + len = le16_to_cpu(nth16->wBlockLength); + if (len > ctx->rx_max) { + pr_debug("unsupported NTB block length %u/%u\n", len, + ctx->rx_max); goto error; } - temp = le16_to_cpu(ctx->rx_ncm.nth16.wNdpIndex); - if ((temp + sizeof(ctx->rx_ncm.ndp16)) > actlen) { - pr_debug("invalid DPT16 index\n"); + if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) && + (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) && + !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) { + pr_debug("sequence number glitch prev=%d curr=%d\n", + ctx->rx_seq, le16_to_cpu(nth16->wSequence)); + } + ctx->rx_seq = le16_to_cpu(nth16->wSequence); + + len = le16_to_cpu(nth16->wNdpIndex); + if ((len + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) { + pr_debug("invalid DPT16 index <%u>\n", + le16_to_cpu(nth16->wNdpIndex)); goto error; } - memcpy(&(ctx->rx_ncm.ndp16), ((u8 *)skb_in->data) + temp, - sizeof(ctx->rx_ncm.ndp16)); + ndp16 = (struct usb_cdc_ncm_ndp16 *)(((u8 *)skb_in->data) + len); - if (le32_to_cpu(ctx->rx_ncm.ndp16.dwSignature) != - USB_CDC_NCM_NDP16_NOCRC_SIGN) { + if (le32_to_cpu(ndp16->dwSignature) != USB_CDC_NCM_NDP16_NOCRC_SIGN) { pr_debug("invalid DPT16 signature <%u>\n", - le32_to_cpu(ctx->rx_ncm.ndp16.dwSignature)); + le32_to_cpu(ndp16->dwSignature)); goto error; } - if (le16_to_cpu(ctx->rx_ncm.ndp16.wLength) < - USB_CDC_NCM_NDP16_LENGTH_MIN) { + if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) { pr_debug("invalid DPT16 length <%u>\n", - le32_to_cpu(ctx->rx_ncm.ndp16.dwSignature)); + le32_to_cpu(ndp16->dwSignature)); goto error; } - nframes = ((le16_to_cpu(ctx->rx_ncm.ndp16.wLength) - + nframes = ((le16_to_cpu(ndp16->wLength) - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16)); nframes--; /* we process NDP entries except for the last one */ - pr_debug("nframes = %u\n", nframes); + len += sizeof(struct usb_cdc_ncm_ndp16); - temp += sizeof(ctx->rx_ncm.ndp16); - - if ((temp + nframes * (sizeof(struct usb_cdc_ncm_dpe16))) > actlen) { + if ((len + nframes * (sizeof(struct usb_cdc_ncm_dpe16))) > + skb_in->len) { pr_debug("Invalid nframes = %d\n", nframes); goto error; } - if (nframes > CDC_NCM_DPT_DATAGRAMS_MAX) { - pr_debug("Truncating number of frames from %u to %u\n", - nframes, CDC_NCM_DPT_DATAGRAMS_MAX); - nframes = CDC_NCM_DPT_DATAGRAMS_MAX; - } - - memcpy(&(ctx->rx_ncm.dpe16), ((u8 *)skb_in->data) + temp, - nframes * (sizeof(struct usb_cdc_ncm_dpe16))); + dpe16 = (struct usb_cdc_ncm_dpe16 *)(((u8 *)skb_in->data) + len); - for (x = 0; x < nframes; x++) { - offset = le16_to_cpu(ctx->rx_ncm.dpe16[x].wDatagramIndex); - temp = le16_to_cpu(ctx->rx_ncm.dpe16[x].wDatagramLength); + for (x = 0; x < nframes; x++, dpe16++) { + offset = le16_to_cpu(dpe16->wDatagramIndex); + len = le16_to_cpu(dpe16->wDatagramLength); /* * CDC NCM ch. 3.7 * All entries after first NULL entry are to be ignored */ - if ((offset == 0) || (temp == 0)) { + if ((offset == 0) || (len == 0)) { if (!x) goto error; /* empty NTB */ break; } /* sanity checking */ - if (((offset + temp) > actlen) || - (temp > CDC_NCM_MAX_DATAGRAM_SIZE) || (temp < ETH_HLEN)) { + if (((offset + len) > skb_in->len) || + (len > ctx->rx_max) || (len < ETH_HLEN)) { pr_debug("invalid frame detected (ignored)" "offset[%u]=%u, length=%u, skb=%p\n", - x, offset, temp, skb_in); + x, offset, len, skb_in); if (!x) goto error; break; @@ -1066,9 +1058,9 @@ static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in) skb = skb_clone(skb_in, GFP_ATOMIC); if (!skb) goto error; - skb->len = temp; + skb->len = len; skb->data = ((u8 *)skb_in->data) + offset; - skb_set_tail_pointer(skb, temp); + skb_set_tail_pointer(skb, len); usbnet_skb_return(dev, skb); } }