* [PATCH] [PATCH] net: sxgbe: Fix waring for double kfree()
@ 2015-01-15 1:43 Kukjin Kim
2015-01-15 8:12 ` Dan Carpenter
2015-01-16 0:14 ` David Miller
0 siblings, 2 replies; 8+ messages in thread
From: Kukjin Kim @ 2015-01-15 1:43 UTC (permalink / raw)
To: netdev; +Cc: Dave Miller, Dan Carpenter, Byungho An, Kukjin Kim
From: Byungho An <bh74.an@samsung.com>
This patch fixes double kfree() calls at init_rx_ring() because
it causes static checker warning.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>
---
drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index 6984944..fe7538d 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -474,13 +474,19 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
/* allocate memory for RX skbuff array */
rx_ring->rx_skbuff_dma = kmalloc_array(rx_rsize,
sizeof(dma_addr_t), GFP_KERNEL);
- if (rx_ring->rx_skbuff_dma == NULL)
- goto dmamem_err;
+ if (!rx_ring->rx_skbuff_dma) {
+ dma_free_coherent(priv->device,
+ rx_rsize * sizeof(struct sxgbe_rx_norm_desc),
+ rx_ring->dma_rx, rx_ring->dma_rx_phy);
+ goto error;
+ }
rx_ring->rx_skbuff = kmalloc_array(rx_rsize,
sizeof(struct sk_buff *), GFP_KERNEL);
- if (rx_ring->rx_skbuff == NULL)
- goto rxbuff_err;
+ if (!rx_ring->rx_skbuff) {
+ kfree(rx_ring->rx_skbuff_dma);
+ goto error;
+ }
/* initialise the buffers */
for (desc_index = 0; desc_index < rx_rsize; desc_index++) {
@@ -502,13 +508,6 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
err_init_rx_buffers:
while (--desc_index >= 0)
free_rx_ring(priv->device, rx_ring, desc_index);
- kfree(rx_ring->rx_skbuff);
-rxbuff_err:
- kfree(rx_ring->rx_skbuff_dma);
-dmamem_err:
- dma_free_coherent(priv->device,
- rx_rsize * sizeof(struct sxgbe_rx_norm_desc),
- rx_ring->dma_rx, rx_ring->dma_rx_phy);
error:
return -ENOMEM;
}
--
2.0.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH] [PATCH] net: sxgbe: Fix waring for double kfree()
2015-01-15 1:43 [PATCH] [PATCH] net: sxgbe: Fix waring for double kfree() Kukjin Kim
@ 2015-01-15 8:12 ` Dan Carpenter
2015-01-16 0:14 ` David Miller
1 sibling, 0 replies; 8+ messages in thread
From: Dan Carpenter @ 2015-01-15 8:12 UTC (permalink / raw)
To: Kukjin Kim; +Cc: netdev, Dave Miller, Byungho An
On Thu, Jan 15, 2015 at 10:43:11AM +0900, Kukjin Kim wrote:
> rx_ring->rx_skbuff = kmalloc_array(rx_rsize,
> sizeof(struct sk_buff *), GFP_KERNEL);
> - if (rx_ring->rx_skbuff == NULL)
> - goto rxbuff_err;
> + if (!rx_ring->rx_skbuff) {
This is missing a dma_free_coherent() here.
> + kfree(rx_ring->rx_skbuff_dma);
> + goto error;
> + }
>
> /* initialise the buffers */
> for (desc_index = 0; desc_index < rx_rsize; desc_index++) {
> @@ -502,13 +508,6 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
> err_init_rx_buffers:
> while (--desc_index >= 0)
> free_rx_ring(priv->device, rx_ring, desc_index);
> - kfree(rx_ring->rx_skbuff);
The double free bug is that free_rx_ring() frees
kfree(rx_ring->rx_skbuff_dma); and kfree(rx_ring->rx_skbuff); so just
calling it in a loop here will cause a double free.
Also free_rx_ring() doesn't take an index parameter, it takes a size
parameter.
The right way to fix this is to create a release function that mirrors
sxgbe_init_rx_buffers().
static void sxgbe_free_rx_buffers(struct net_device *dev,
struct sxgbe_rx_norm_desc *p, int i,
unsigned int dma_buf_sz,
struct sxgbe_rx_queue *rx_ring)
{
struct sxgbe_priv_data *priv = netdev_priv(dev);
kfree_skb(rx_ring->rx_skbuff[i]);
dma_unmap_single(priv->device, rx_ring->rx_skbuff_dma[i],
dma_buf_sz, DMA_FROM_DEVICE);
}
Then just swap that into the free loop instead of the free_rx_ring().
err_init_rx_buffers:
while (--desc_index >= 0) {
struct sxgbe_rx_norm_desc *p;
p = rx_ring->dma_rx + desc_index;
sxgbe_init_rx_buffers(dev, p, desc_index, bfsize, rx_ring);
}
kfree(rx_ring->rx_skbuff);
Something like that.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] [PATCH] net: sxgbe: Fix waring for double kfree()
2015-01-15 1:43 [PATCH] [PATCH] net: sxgbe: Fix waring for double kfree() Kukjin Kim
2015-01-15 8:12 ` Dan Carpenter
@ 2015-01-16 0:14 ` David Miller
2015-01-16 7:12 ` Dan Carpenter
1 sibling, 1 reply; 8+ messages in thread
From: David Miller @ 2015-01-16 0:14 UTC (permalink / raw)
To: kgene; +Cc: netdev, davem, dan.carpenter, bh74.an
From: Kukjin Kim <kgene@kernel.org>
Date: Thu, 15 Jan 2015 10:43:11 +0900
> From: Byungho An <bh74.an@samsung.com>
>
> This patch fixes double kfree() calls at init_rx_ring() because
> it causes static checker warning.
>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> Signed-off-by: Byungho An <bh74.an@samsung.com>
> Signed-off-by: Kukjin Kim <kgene@kernel.org>
Applied.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] [PATCH] net: sxgbe: Fix waring for double kfree()
2015-01-16 0:14 ` David Miller
@ 2015-01-16 7:12 ` Dan Carpenter
2015-02-05 8:00 ` Dan Carpenter
0 siblings, 1 reply; 8+ messages in thread
From: Dan Carpenter @ 2015-01-16 7:12 UTC (permalink / raw)
To: David Miller; +Cc: kgene, netdev, davem, bh74.an
On Thu, Jan 15, 2015 at 07:14:16PM -0500, David Miller wrote:
> From: Kukjin Kim <kgene@kernel.org>
> Date: Thu, 15 Jan 2015 10:43:11 +0900
>
> > From: Byungho An <bh74.an@samsung.com>
> >
> > This patch fixes double kfree() calls at init_rx_ring() because
> > it causes static checker warning.
> >
> > Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> > Signed-off-by: Byungho An <bh74.an@samsung.com>
> > Signed-off-by: Kukjin Kim <kgene@kernel.org>
>
> Applied.
It does silence the warning but it doesn't fix the bug.
Kukjin, let me know if you have any questions. I can write the fix if
you need me to.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 8+ messages in thread
* [patch] net: sxgbe: fix error handling in init_rx_ring()
2015-01-16 7:12 ` Dan Carpenter
@ 2015-02-05 8:00 ` Dan Carpenter
0 siblings, 0 replies; 8+ messages in thread
From: Dan Carpenter @ 2015-02-05 8:00 UTC (permalink / raw)
To: Byungho An, kgene; +Cc: Girish K S, Vipul Pandya, netdev, kernel-janitors
There are a couple bugs with the error handling in this function.
1) If we can't allocate "rx_ring->rx_skbuff" then we should call
dma_free_coherent() but we don't.
2) free_rx_ring() frees "rx_ring->rx_skbuff_dma" and "rx_ring->rx_skbuff"
so calling it in a loop causes a double free.
Also it was a bit confusing how we sometimes freed things before doing
the goto. I've cleaned it up so it does error handling in normal kernel
style.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index 11288d4..c8a01ee 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -364,6 +364,26 @@ static int sxgbe_init_rx_buffers(struct net_device *dev,
return 0;
}
+
+/**
+ * sxgbe_free_rx_buffers - free what sxgbe_init_rx_buffers() allocated
+ * @dev: net device structure
+ * @rx_ring: ring to be freed
+ * @rx_rsize: ring size
+ * Description: this function initializes the DMA RX descriptor
+ */
+static void sxgbe_free_rx_buffers(struct net_device *dev,
+ struct sxgbe_rx_norm_desc *p, int i,
+ unsigned int dma_buf_sz,
+ struct sxgbe_rx_queue *rx_ring)
+{
+ struct sxgbe_priv_data *priv = netdev_priv(dev);
+
+ kfree_skb(rx_ring->rx_skbuff[i]);
+ dma_unmap_single(priv->device, rx_ring->rx_skbuff_dma[i],
+ dma_buf_sz, DMA_FROM_DEVICE);
+}
+
/**
* init_tx_ring - init the TX descriptor ring
* @dev: net device structure
@@ -456,7 +476,7 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
/* RX ring is not allcoated */
if (rx_ring == NULL) {
netdev_err(dev, "No memory for RX queue\n");
- goto error;
+ return -ENOMEM;
}
/* assign queue number */
@@ -468,23 +488,21 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
&rx_ring->dma_rx_phy, GFP_KERNEL);
if (rx_ring->dma_rx == NULL)
- goto error;
+ return -ENOMEM;
/* allocate memory for RX skbuff array */
rx_ring->rx_skbuff_dma = kmalloc_array(rx_rsize,
sizeof(dma_addr_t), GFP_KERNEL);
if (!rx_ring->rx_skbuff_dma) {
- dma_free_coherent(priv->device,
- rx_rsize * sizeof(struct sxgbe_rx_norm_desc),
- rx_ring->dma_rx, rx_ring->dma_rx_phy);
- goto error;
+ ret = -ENOMEM;
+ goto err_free_dma_rx;
}
rx_ring->rx_skbuff = kmalloc_array(rx_rsize,
sizeof(struct sk_buff *), GFP_KERNEL);
if (!rx_ring->rx_skbuff) {
- kfree(rx_ring->rx_skbuff_dma);
- goto error;
+ ret = -ENOMEM;
+ goto err_free_skbuff_dma;
}
/* initialise the buffers */
@@ -494,7 +512,7 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
ret = sxgbe_init_rx_buffers(dev, p, desc_index,
bfsize, rx_ring);
if (ret)
- goto err_init_rx_buffers;
+ goto err_free_rx_buffers;
}
/* initalise counters */
@@ -504,11 +522,22 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
return 0;
-err_init_rx_buffers:
- while (--desc_index >= 0)
- free_rx_ring(priv->device, rx_ring, desc_index);
-error:
- return -ENOMEM;
+err_free_rx_buffers:
+ while (--desc_index >= 0) {
+ struct sxgbe_rx_norm_desc *p;
+
+ p = rx_ring->dma_rx + desc_index;
+ sxgbe_free_rx_buffers(dev, p, desc_index, bfsize, rx_ring);
+ }
+ kfree(rx_ring->rx_skbuff);
+err_free_skbuff_dma:
+ kfree(rx_ring->rx_skbuff_dma);
+err_free_dma_rx:
+ dma_free_coherent(priv->device,
+ rx_rsize * sizeof(struct sxgbe_rx_norm_desc),
+ rx_ring->dma_rx, rx_ring->dma_rx_phy);
+
+ return ret;
}
/**
* free_tx_ring - free the TX descriptor ring
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [patch] net: sxgbe: fix error handling in init_rx_ring()
@ 2015-02-05 8:00 ` Dan Carpenter
0 siblings, 0 replies; 8+ messages in thread
From: Dan Carpenter @ 2015-02-05 8:00 UTC (permalink / raw)
To: Byungho An, kgene; +Cc: Girish K S, Vipul Pandya, netdev, kernel-janitors
There are a couple bugs with the error handling in this function.
1) If we can't allocate "rx_ring->rx_skbuff" then we should call
dma_free_coherent() but we don't.
2) free_rx_ring() frees "rx_ring->rx_skbuff_dma" and "rx_ring->rx_skbuff"
so calling it in a loop causes a double free.
Also it was a bit confusing how we sometimes freed things before doing
the goto. I've cleaned it up so it does error handling in normal kernel
style.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index 11288d4..c8a01ee 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -364,6 +364,26 @@ static int sxgbe_init_rx_buffers(struct net_device *dev,
return 0;
}
+
+/**
+ * sxgbe_free_rx_buffers - free what sxgbe_init_rx_buffers() allocated
+ * @dev: net device structure
+ * @rx_ring: ring to be freed
+ * @rx_rsize: ring size
+ * Description: this function initializes the DMA RX descriptor
+ */
+static void sxgbe_free_rx_buffers(struct net_device *dev,
+ struct sxgbe_rx_norm_desc *p, int i,
+ unsigned int dma_buf_sz,
+ struct sxgbe_rx_queue *rx_ring)
+{
+ struct sxgbe_priv_data *priv = netdev_priv(dev);
+
+ kfree_skb(rx_ring->rx_skbuff[i]);
+ dma_unmap_single(priv->device, rx_ring->rx_skbuff_dma[i],
+ dma_buf_sz, DMA_FROM_DEVICE);
+}
+
/**
* init_tx_ring - init the TX descriptor ring
* @dev: net device structure
@@ -456,7 +476,7 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
/* RX ring is not allcoated */
if (rx_ring = NULL) {
netdev_err(dev, "No memory for RX queue\n");
- goto error;
+ return -ENOMEM;
}
/* assign queue number */
@@ -468,23 +488,21 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
&rx_ring->dma_rx_phy, GFP_KERNEL);
if (rx_ring->dma_rx = NULL)
- goto error;
+ return -ENOMEM;
/* allocate memory for RX skbuff array */
rx_ring->rx_skbuff_dma = kmalloc_array(rx_rsize,
sizeof(dma_addr_t), GFP_KERNEL);
if (!rx_ring->rx_skbuff_dma) {
- dma_free_coherent(priv->device,
- rx_rsize * sizeof(struct sxgbe_rx_norm_desc),
- rx_ring->dma_rx, rx_ring->dma_rx_phy);
- goto error;
+ ret = -ENOMEM;
+ goto err_free_dma_rx;
}
rx_ring->rx_skbuff = kmalloc_array(rx_rsize,
sizeof(struct sk_buff *), GFP_KERNEL);
if (!rx_ring->rx_skbuff) {
- kfree(rx_ring->rx_skbuff_dma);
- goto error;
+ ret = -ENOMEM;
+ goto err_free_skbuff_dma;
}
/* initialise the buffers */
@@ -494,7 +512,7 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
ret = sxgbe_init_rx_buffers(dev, p, desc_index,
bfsize, rx_ring);
if (ret)
- goto err_init_rx_buffers;
+ goto err_free_rx_buffers;
}
/* initalise counters */
@@ -504,11 +522,22 @@ static int init_rx_ring(struct net_device *dev, u8 queue_no,
return 0;
-err_init_rx_buffers:
- while (--desc_index >= 0)
- free_rx_ring(priv->device, rx_ring, desc_index);
-error:
- return -ENOMEM;
+err_free_rx_buffers:
+ while (--desc_index >= 0) {
+ struct sxgbe_rx_norm_desc *p;
+
+ p = rx_ring->dma_rx + desc_index;
+ sxgbe_free_rx_buffers(dev, p, desc_index, bfsize, rx_ring);
+ }
+ kfree(rx_ring->rx_skbuff);
+err_free_skbuff_dma:
+ kfree(rx_ring->rx_skbuff_dma);
+err_free_dma_rx:
+ dma_free_coherent(priv->device,
+ rx_rsize * sizeof(struct sxgbe_rx_norm_desc),
+ rx_ring->dma_rx, rx_ring->dma_rx_phy);
+
+ return ret;
}
/**
* free_tx_ring - free the TX descriptor ring
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [patch] net: sxgbe: fix error handling in init_rx_ring()
2015-02-05 8:00 ` Dan Carpenter
@ 2015-02-06 20:50 ` David Miller
-1 siblings, 0 replies; 8+ messages in thread
From: David Miller @ 2015-02-06 20:50 UTC (permalink / raw)
To: dan.carpenter
Cc: bh74.an, kgene, ks.giri, vipul.pandya, netdev, kernel-janitors
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 5 Feb 2015 11:00:42 +0300
> There are a couple bugs with the error handling in this function.
>
> 1) If we can't allocate "rx_ring->rx_skbuff" then we should call
> dma_free_coherent() but we don't.
> 2) free_rx_ring() frees "rx_ring->rx_skbuff_dma" and "rx_ring->rx_skbuff"
> so calling it in a loop causes a double free.
>
> Also it was a bit confusing how we sometimes freed things before doing
> the goto. I've cleaned it up so it does error handling in normal kernel
> style.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Looks good, applied, thanks Dan.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [patch] net: sxgbe: fix error handling in init_rx_ring()
@ 2015-02-06 20:50 ` David Miller
0 siblings, 0 replies; 8+ messages in thread
From: David Miller @ 2015-02-06 20:50 UTC (permalink / raw)
To: dan.carpenter
Cc: bh74.an, kgene, ks.giri, vipul.pandya, netdev, kernel-janitors
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 5 Feb 2015 11:00:42 +0300
> There are a couple bugs with the error handling in this function.
>
> 1) If we can't allocate "rx_ring->rx_skbuff" then we should call
> dma_free_coherent() but we don't.
> 2) free_rx_ring() frees "rx_ring->rx_skbuff_dma" and "rx_ring->rx_skbuff"
> so calling it in a loop causes a double free.
>
> Also it was a bit confusing how we sometimes freed things before doing
> the goto. I've cleaned it up so it does error handling in normal kernel
> style.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Looks good, applied, thanks Dan.
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2015-02-06 20:50 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-01-15 1:43 [PATCH] [PATCH] net: sxgbe: Fix waring for double kfree() Kukjin Kim
2015-01-15 8:12 ` Dan Carpenter
2015-01-16 0:14 ` David Miller
2015-01-16 7:12 ` Dan Carpenter
2015-02-05 8:00 ` [patch] net: sxgbe: fix error handling in init_rx_ring() Dan Carpenter
2015-02-05 8:00 ` Dan Carpenter
2015-02-06 20:50 ` David Miller
2015-02-06 20:50 ` David Miller
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