diff mbox

net: phy: smsc: fix buffer overflow in memcpy

Message ID 20170620204059.790066-1-arnd@arndb.de
State Accepted
Commit 2da55390a96ad2245edfaca77669c10088523d39
Headers show

Commit Message

Arnd Bergmann June 20, 2017, 8:40 p.m. UTC
The memcpy annotation triggers for a fixed-length buffer copy:

In file included from /git/arm-soc/arch/arm64/include/asm/processor.h:30:0,
                 from /git/arm-soc/arch/arm64/include/asm/spinlock.h:21,
                 from /git/arm-soc/include/linux/spinlock.h:87,
                 from /git/arm-soc/include/linux/seqlock.h:35,
                 from /git/arm-soc/include/linux/time.h:5,
                 from /git/arm-soc/include/linux/stat.h:21,
                 from /git/arm-soc/include/linux/module.h:10,
                 from /git/arm-soc/drivers/net/phy/smsc.c:20:
In function 'memcpy',
    inlined from 'smsc_get_strings' at /git/arm-soc/drivers/net/phy/smsc.c:166:3:
/git/arm-soc/include/linux/string.h:309:4: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter

Using strncpy instead of memcpy should do the right thing here.

Fixes: 030a89028db0 ("net: phy: smsc: Implement PHY statistics")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

---
 drivers/net/phy/smsc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

-- 
2.9.0

Comments

Andrew Lunn June 20, 2017, 9:46 p.m. UTC | #1
On Tue, Jun 20, 2017 at 10:40:46PM +0200, Arnd Bergmann wrote:
> The memcpy annotation triggers for a fixed-length buffer copy:

> 

> In file included from /git/arm-soc/arch/arm64/include/asm/processor.h:30:0,

>                  from /git/arm-soc/arch/arm64/include/asm/spinlock.h:21,

>                  from /git/arm-soc/include/linux/spinlock.h:87,

>                  from /git/arm-soc/include/linux/seqlock.h:35,

>                  from /git/arm-soc/include/linux/time.h:5,

>                  from /git/arm-soc/include/linux/stat.h:21,

>                  from /git/arm-soc/include/linux/module.h:10,

>                  from /git/arm-soc/drivers/net/phy/smsc.c:20:

> In function 'memcpy',

>     inlined from 'smsc_get_strings' at /git/arm-soc/drivers/net/phy/smsc.c:166:3:

> /git/arm-soc/include/linux/string.h:309:4: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter

> 

> Using strncpy instead of memcpy should do the right thing here.


Hi Arnd

You will find this pattern in number of phy drivers:

bcm-phy-lib.c:	   	   memcpy(data + i * ETH_GSTRING_LEN,
marvell.c:			       		   memcpy(data + i * ETH_GSTRING_LEN,
micrel.c:   		memcpy(data + i * ETH_GSTRING_LEN,
smsc.c:				    memcpy(data + i * ETH_GSTRING_LEN,

They probably all need the same fix.

     Andrew
David Miller June 22, 2017, 3:12 p.m. UTC | #2
From: Arnd Bergmann <arnd@arndb.de>

Date: Tue, 20 Jun 2017 22:40:46 +0200

> The memcpy annotation triggers for a fixed-length buffer copy:

> 

> In file included from /git/arm-soc/arch/arm64/include/asm/processor.h:30:0,

>                  from /git/arm-soc/arch/arm64/include/asm/spinlock.h:21,

>                  from /git/arm-soc/include/linux/spinlock.h:87,

>                  from /git/arm-soc/include/linux/seqlock.h:35,

>                  from /git/arm-soc/include/linux/time.h:5,

>                  from /git/arm-soc/include/linux/stat.h:21,

>                  from /git/arm-soc/include/linux/module.h:10,

>                  from /git/arm-soc/drivers/net/phy/smsc.c:20:

> In function 'memcpy',

>     inlined from 'smsc_get_strings' at /git/arm-soc/drivers/net/phy/smsc.c:166:3:

> /git/arm-soc/include/linux/string.h:309:4: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter

> 

> Using strncpy instead of memcpy should do the right thing here.

> 

> Fixes: 030a89028db0 ("net: phy: smsc: Implement PHY statistics")

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>


APplied to net-next, thanks Arnd.
diff mbox

Patch

diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c
index 1b8204be064c..2306bfae057f 100644
--- a/drivers/net/phy/smsc.c
+++ b/drivers/net/phy/smsc.c
@@ -163,7 +163,7 @@  static void smsc_get_strings(struct phy_device *phydev, u8 *data)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++) {
-		memcpy(data + i * ETH_GSTRING_LEN,
+		strncpy(data + i * ETH_GSTRING_LEN,
 		       smsc_hw_stats[i].string, ETH_GSTRING_LEN);
 	}
 }