2011-03-04 18:08:42

by j223yang

Subject: [Patch] ariadne: fix possible null dereference

This patch fixes bugzilla #13853:
https://bugzilla.kernel.org/show_bug.cgi?id=13853

The patch removes dereference of 'dev' after testing for NULL.
The source code ariadne.c uses spaces instead of tabs, so the patch
uses spaces too.

Signed-off-by: Jinqiu Yang<[email protected]>
---
drivers/net/ariadne.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ariadne.c b/drivers/net/ariadne.c
--- a/drivers/net/ariadne.c
+++ b/drivers/net/ariadne.c
@@ -420,7 +420,7 @@ static inline void ariadne_reset(struct
static irqreturn_t ariadne_interrupt(int irq, void *data)
{
struct net_device *dev = (struct net_device *)data;
- volatile struct Am79C960 *lance = (struct Am79C960*)dev->base_addr;
+ volatile struct Am79C960 *lance;
struct ariadne_private *priv;
int csr0, boguscnt;
int handled = 0;
@@ -430,6 +430,7 @@ static irqreturn_t ariadne_interrupt(int
return IRQ_NONE;
}

+ lance = (struct Am79C960 *)dev->base_addr;
lance->RAP = CSR0; /* PCnet-ISA Controller Status */

if (!(lance->RDP & INTR)) /* Check if any interrupt has been */

2011-03-04 18:31:26

by Randy Dunlap

Subject: Re: [Patch] ariadne: fix possible null dereference

On Fri, 4 Mar 2011 12:46:26 -0500 [email protected] wrote:

> This patch fixes bugzilla #13853:
> https://bugzilla.kernel.org/show_bug.cgi?id=13853
>
> The patch removes dereference of 'dev' after testing for NULL.
> The source code ariadne.c uses spaces instead of tabs, so the patch
> uses spaces too.

Sorry for the confusion here, but (while I agree with the fix in this
patch), this patch still does not apply cleanly.

If a line in the source code file uses spaces, then use spaces.
If a line in the source code file uses tabs, then use tabs.

You cannot exchange one for the other in your generated patch.
Using 'diff' creates the patch correctly, so I guess that your patch
generation tool still needs some work.

Please take your patch and test applying it:

> cd linux-2.6.38-rc7
> patch -p1 --dry-run < ~/tmp/ariadne.patch
patching file drivers/net/ariadne.c
Hunk #2 FAILED at 430.
1 out of 2 hunks FAILED -- saving rejects to file drivers/net/ariadne.c.rej


> Signed-off-by: Jinqiu Yang<[email protected]>
> ---
> drivers/net/ariadne.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ariadne.c b/drivers/net/ariadne.c
> --- a/drivers/net/ariadne.c
> +++ b/drivers/net/ariadne.c
> @@ -420,7 +420,7 @@ static inline void ariadne_reset(struct
> static irqreturn_t ariadne_interrupt(int irq, void *data)
> {
> struct net_device *dev = (struct net_device *)data;
> - volatile struct Am79C960 *lance = (struct Am79C960*)dev->base_addr;
> + volatile struct Am79C960 *lance;
> struct ariadne_private *priv;
> int csr0, boguscnt;
> int handled = 0;
> @@ -430,6 +430,7 @@ static irqreturn_t ariadne_interrupt(int
> return IRQ_NONE;
> }
>
> + lance = (struct Am79C960 *)dev->base_addr;
> lance->RAP = CSR0; /* PCnet-ISA Controller Status */
>
> if (!(lance->RDP & INTR)) /* Check if any interrupt has been */
>
> --

---
~Randy
*** Remember to use Documentation/SubmitChecklist when testing your code ***