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kernel: bgmac: rework patch checking packet length
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This bgmac patch was an attempt to fix/workaround bug reported in
https://dev.openwrt.org/ticket/7198 noticed on WNR3500L.
Patch assumed length reported by the hardware was 0 and was trying to
read it until getting a different value. This was actually the opposite.
Lenghts were some invalid & huge values that resulted in skb_over_panic.
For example:
skbuff: skb_over_panic: text:83b21074 len:57222 (...)
skbuff: skb_over_panic: text:87af1024 len:43226 (...)
skbuff: skb_over_panic: text:87af5024 len:8739 (...)

So instead of that not-working patch checking for 0, write a new one
checking for huge values. In case something like that happens, dump
hardware state and drop the packet.

Signed-off-by: Rafał Miłecki <[email protected]>


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@40424 3c298f89-4303-0410-b956-a3cf2f4a3e73
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hauke committed Apr 8, 2014
1 parent 1972881 commit 421797f
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Showing 4 changed files with 141 additions and 26 deletions.
50 changes: 24 additions & 26 deletions target/linux/generic/patches-3.10/775-bgmac-check-length-of-received-frame.patch
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Original file line number Diff line number Diff line change
Expand Up @@ -9,33 +9,31 @@ Subject: [PATCH] bgmac: check length of received frame

--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -349,6 +349,7 @@ static int bgmac_dma_rx_read(struct bgma
struct sk_buff *skb = slot->skb;
struct bgmac_rx_header *rx;
u16 len, flags;
+ int count;

/* Unmap buffer to make it accessible to the CPU */
dma_sync_single_for_cpu(dma_dev, slot->dma_addr,
@@ -357,6 +358,12 @@ static int bgmac_dma_rx_read(struct bgma
/* Get info from the header */
rx = (struct bgmac_rx_header *)skb->data;
len = le16_to_cpu(rx->len);
+ for (count = 0; count < 200; count++) {
+ len = le16_to_cpu(rx->len);
+ if (len)
+ break;
+ udelay(1);
+ }
flags = le16_to_cpu(rx->flags);

do {
@@ -364,7 +371,7 @@ static int bgmac_dma_rx_read(struct bgma
@@ -363,6 +363,27 @@ static int bgmac_dma_rx_read(struct bgma
dma_addr_t old_dma_addr = slot->dma_addr;
int err;

+ if (len > BGMAC_RX_MAX_FRAME_SIZE) {
+ struct bgmac_dma_desc *dma_desc = ring->cpu_base + ring->start;
+
+ bgmac_err(bgmac, "Hardware reported invalid packet length %d for slot %d!\n", len, ring->start);
+ bgmac_err(bgmac, "flags: 0x%04X\n", flags);
+ bgmac_err(bgmac, "ctl0: 0x%08X\tctl1: 0x%08X\n", le32_to_cpu(dma_desc->ctl0), le32_to_cpu(dma_desc->ctl1));
+
+ bgmac_err(bgmac, " BGMAC_DMA_RX_CTL: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_CTL));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_INDEX: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGLO: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGLO));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGHI: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGHI));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_STATUS: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_STATUS));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_ERROR: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_ERROR));
+
+ dma_sync_single_for_device(dma_dev,
+ slot->dma_addr,
+ BGMAC_RX_BUF_SIZE,
+ DMA_FROM_DEVICE);
+ break;
+ }
+
/* Check for poison and drop or pass the packet */
- if (len == 0xdead && flags == 0xbeef) {
+ if (!len || (len == 0xdead && flags == 0xbeef)) {
if (len == 0xdead && flags == 0xbeef) {
bgmac_err(bgmac, "Found poisoned packet at slot %d, DMA issue!\n",
ring->start);
dma_sync_single_for_device(dma_dev,
39 changes: 39 additions & 0 deletions target/linux/generic/patches-3.12/775-bgmac-check-length-of-received-frame.patch
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Original file line number Diff line number Diff line change
@@ -0,0 +1,39 @@
From 2d12a9abf3f81de5b51852e3cfcba8cedac82642 Mon Sep 17 00:00:00 2001
From: Hauke Mehrtens <[email protected]>
Date: Fri, 6 Dec 2013 01:14:52 +0100
Subject: [PATCH] bgmac: check length of received frame

---
drivers/net/ethernet/broadcom/bgmac.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -363,6 +363,27 @@ static int bgmac_dma_rx_read(struct bgma
dma_addr_t old_dma_addr = slot->dma_addr;
int err;

+ if (len > BGMAC_RX_MAX_FRAME_SIZE) {
+ struct bgmac_dma_desc *dma_desc = ring->cpu_base + ring->start;
+
+ bgmac_err(bgmac, "Hardware reported invalid packet length %d for slot %d!\n", len, ring->start);
+ bgmac_err(bgmac, "flags: 0x%04X\n", flags);
+ bgmac_err(bgmac, "ctl0: 0x%08X\tctl1: 0x%08X\n", le32_to_cpu(dma_desc->ctl0), le32_to_cpu(dma_desc->ctl1));
+
+ bgmac_err(bgmac, " BGMAC_DMA_RX_CTL: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_CTL));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_INDEX: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGLO: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGLO));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGHI: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGHI));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_STATUS: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_STATUS));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_ERROR: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_ERROR));
+
+ dma_sync_single_for_device(dma_dev,
+ slot->dma_addr,
+ BGMAC_RX_BUF_SIZE,
+ DMA_FROM_DEVICE);
+ break;
+ }
+
/* Check for poison and drop or pass the packet */
if (len == 0xdead && flags == 0xbeef) {
bgmac_err(bgmac, "Found poisoned packet at slot %d, DMA issue!\n",
39 changes: 39 additions & 0 deletions target/linux/generic/patches-3.13/775-bgmac-check-length-of-received-frame.patch
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Original file line number Diff line number Diff line change
@@ -0,0 +1,39 @@
From 2d12a9abf3f81de5b51852e3cfcba8cedac82642 Mon Sep 17 00:00:00 2001
From: Hauke Mehrtens <[email protected]>
Date: Fri, 6 Dec 2013 01:14:52 +0100
Subject: [PATCH] bgmac: check length of received frame

---
drivers/net/ethernet/broadcom/bgmac.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -363,6 +363,27 @@ static int bgmac_dma_rx_read(struct bgma
dma_addr_t old_dma_addr = slot->dma_addr;
int err;

+ if (len > BGMAC_RX_MAX_FRAME_SIZE) {
+ struct bgmac_dma_desc *dma_desc = ring->cpu_base + ring->start;
+
+ bgmac_err(bgmac, "Hardware reported invalid packet length %d for slot %d!\n", len, ring->start);
+ bgmac_err(bgmac, "flags: 0x%04X\n", flags);
+ bgmac_err(bgmac, "ctl0: 0x%08X\tctl1: 0x%08X\n", le32_to_cpu(dma_desc->ctl0), le32_to_cpu(dma_desc->ctl1));
+
+ bgmac_err(bgmac, " BGMAC_DMA_RX_CTL: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_CTL));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_INDEX: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGLO: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGLO));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGHI: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGHI));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_STATUS: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_STATUS));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_ERROR: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_ERROR));
+
+ dma_sync_single_for_device(dma_dev,
+ slot->dma_addr,
+ BGMAC_RX_BUF_SIZE,
+ DMA_FROM_DEVICE);
+ break;
+ }
+
/* Check for poison and drop or pass the packet */
if (len == 0xdead && flags == 0xbeef) {
bgmac_err(bgmac, "Found poisoned packet at slot %d, DMA issue!\n",
39 changes: 39 additions & 0 deletions target/linux/generic/patches-3.14/775-bgmac-check-length-of-received-frame.patch
View file
Original file line number Diff line number Diff line change
@@ -0,0 +1,39 @@
From 2d12a9abf3f81de5b51852e3cfcba8cedac82642 Mon Sep 17 00:00:00 2001
From: Hauke Mehrtens <[email protected]>
Date: Fri, 6 Dec 2013 01:14:52 +0100
Subject: [PATCH] bgmac: check length of received frame

---
drivers/net/ethernet/broadcom/bgmac.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -363,6 +363,27 @@ static int bgmac_dma_rx_read(struct bgma
dma_addr_t old_dma_addr = slot->dma_addr;
int err;

+ if (len > BGMAC_RX_MAX_FRAME_SIZE) {
+ struct bgmac_dma_desc *dma_desc = ring->cpu_base + ring->start;
+
+ bgmac_err(bgmac, "Hardware reported invalid packet length %d for slot %d!\n", len, ring->start);
+ bgmac_err(bgmac, "flags: 0x%04X\n", flags);
+ bgmac_err(bgmac, "ctl0: 0x%08X\tctl1: 0x%08X\n", le32_to_cpu(dma_desc->ctl0), le32_to_cpu(dma_desc->ctl1));
+
+ bgmac_err(bgmac, " BGMAC_DMA_RX_CTL: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_CTL));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_INDEX: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGLO: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGLO));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_RINGHI: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGHI));
+ bgmac_err(bgmac, "BGMAC_DMA_RX_STATUS: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_STATUS));
+ bgmac_err(bgmac, " BGMAC_DMA_RX_ERROR: 0x%08X\n", bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_ERROR));
+
+ dma_sync_single_for_device(dma_dev,
+ slot->dma_addr,
+ BGMAC_RX_BUF_SIZE,
+ DMA_FROM_DEVICE);
+ break;
+ }
+
/* Check for poison and drop or pass the packet */
if (len == 0xdead && flags == 0xbeef) {
bgmac_err(bgmac, "Found poisoned packet at slot %d, DMA issue!\n",

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