[PATCH] scsi: integer overflow in megadev_ioctl()

[PATCH] scsi: integer overflow in megadev_ioctl()

[Chen.Yu]

From: "Chen.Yu" <chyyuu@gmail.com>

There is a potential integer overflow in megadev_ioctl() if
userspace passes in a large u32 variable uioc.adapno.
The int variable adapno would < 0, leading to an error
array access for hdb_soft_state[adapno], or an error
copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,..)

Reported-by: Wenliang Fan <fanwlexca@gmail.com>
Suggested-by: Qixue Xiao <xiaoqixue_1@163.com>
Signed-off-by: Yu Chen <chyyuu@gmail.com>
Reviewed-by: Levente Kurusa <levex@linux.com>
---
 drivers/scsi/megaraid.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index 816db12..0b90c54 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -3099,7 +3099,10 @@ megadev_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 		/*
 		 * Which adapter
 		 */
-		if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
+		adapno = GETADAP(uioc.adapno);
+		if( adapno < 0 )
+			return (-EINVAL);
+		if( adapno >= hba_count )
 			return (-ENODEV);
 
 		if( copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,
@@ -3113,7 +3116,10 @@ megadev_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 		/*
 		 * Which adapter
 		 */
-		if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
+		adapno = GETADAP(uioc.adapno);
+		if( adapno < 0 )
+			return (-EINVAL);
+		if( adapno >= hba_count )
 			return (-ENODEV);
 
 		adapter = hba_soft_state[adapno];
@@ -3160,7 +3166,10 @@ megadev_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 		/*
 		 * Which adapter
 		 */
-		if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
+		adapno = GETADAP(uioc.adapno);
+		if( adapno < 0 )
+			return (-EINVAL);
+		if( adapno >= hba_count )
 			return (-ENODEV);
 
 		adapter = hba_soft_state[adapno];
-- 
1.8.3.2

Re: [PATCH] scsi: integer overflow in megadev_ioctl()

[Måns Rullgård]

"Chen.Yu" <chyyuu@gmail.com> writes:

> From: "Chen.Yu" <chyyuu@gmail.com>
>
> There is a potential integer overflow in megadev_ioctl() if
> userspace passes in a large u32 variable uioc.adapno.
> The int variable adapno would < 0, leading to an error
> array access for hdb_soft_state[adapno], or an error
> copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,..)
>
> Reported-by: Wenliang Fan <fanwlexca@gmail.com>
> Suggested-by: Qixue Xiao <xiaoqixue_1@163.com>
> Signed-off-by: Yu Chen <chyyuu@gmail.com>
> Reviewed-by: Levente Kurusa <levex@linux.com>
> ---
>  drivers/scsi/megaraid.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
> index 816db12..0b90c54 100644
> --- a/drivers/scsi/megaraid.c
> +++ b/drivers/scsi/megaraid.c
> @@ -3099,7 +3099,10 @@ megadev_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
>  		/*
>  		 * Which adapter
>  		 */
> -		if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
> +		adapno = GETADAP(uioc.adapno);
> +		if( adapno < 0 )
> +			return (-EINVAL);
> +		if( adapno >= hba_count )
>  			return (-ENODEV);

This relies on implementation-defined behaviour when converting an
unsigned integer to signed integer.  A simpler and more robust fix is to
make the local variable 'adapno' unsigned.

-- 
Måns Rullgård
mans@mansr.com

Re: [PATCH] scsi: integer overflow in megadev_ioctl()

[Yu Chen]

I agree that the simpler fix is to change the type of 'adapno' to u32,
which is the type of uioc.adapno to u32.


2013/12/14 Måns Rullgård <mans@mansr.com>:
> "Chen.Yu" <chyyuu@gmail.com> writes:
>
>> From: "Chen.Yu" <chyyuu@gmail.com>
>>
>> There is a potential integer overflow in megadev_ioctl() if
>> userspace passes in a large u32 variable uioc.adapno.
>> The int variable adapno would < 0, leading to an error
>> array access for hdb_soft_state[adapno], or an error
>> copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,..)
>>
>> Reported-by: Wenliang Fan <fanwlexca@gmail.com>
>> Suggested-by: Qixue Xiao <xiaoqixue_1@163.com>
>> Signed-off-by: Yu Chen <chyyuu@gmail.com>
>> Reviewed-by: Levente Kurusa <levex@linux.com>
>> ---
>>  drivers/scsi/megaraid.c | 15 ++++++++++++---
>>  1 file changed, 12 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
>> index 816db12..0b90c54 100644
>> --- a/drivers/scsi/megaraid.c
>> +++ b/drivers/scsi/megaraid.c
>> @@ -3099,7 +3099,10 @@ megadev_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
>>               /*
>>                * Which adapter
>>                */
>> -             if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
>> +             adapno = GETADAP(uioc.adapno);
>> +             if( adapno < 0 )
>> +                     return (-EINVAL);
>> +             if( adapno >= hba_count )
>>                       return (-ENODEV);
>
> This relies on implementation-defined behaviour when converting an
> unsigned integer to signed integer.  A simpler and more robust fix is to
> make the local variable 'adapno' unsigned.
>
> --
> Måns Rullgård
> mans@mansr.com



--

[PATCH] scsi: integer overflow in megadev_ioctl()

[Chen.Yu]

From: "Chen.Yu" <chyyuu@gmail.com>

There is a potential integer overflow in megadev_ioctl() if
userspace passes in a large u32 variable uioc.adapno.
The int variable adapno would < 0, leading to an error
array access for hdb_soft_state[adapno], or an error
copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,..).
The simple fix is to  the simpler fix is to change the type
of 'adapno' to u32, which is the type of uioc.adapno to u32.

Signed-off-by: Yu Chen <chyyuu@gmail.com>
---
 drivers/scsi/megaraid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index 816db12..724c5a5 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -3038,7 +3038,7 @@ megadev_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 {
 	adapter_t	*adapter;
 	nitioctl_t	uioc;
-	int		adapno;
+	u32		adapno;
 	int		rval;
 	mega_passthru	__user *upthru;	/* user address for passthru */
 	mega_passthru	*pthru;		/* copy user passthru here */
-- 
1.8.3.2

Re: [PATCH] scsi: integer overflow in megadev_ioctl()

[Levente Kurusa]

On 12/13/2013 06:31 PM, Yu Chen wrote:
> Thank you!  The new patch
> -------------------------------------------------------------
> [PATCH] scsi: integer overflow in megadev_ioctl()
> 
> There is a potential integer overflow in megadev_ioctl() if
> userspace passes in a large u32 variable uioc.adapno.
> Theint variable adapno would < 0, leading to a error
Typo here, 'theint' should be 'the int'
also it should be 'an error' instead of 'a error'

> array access for hdb_soft_state[adapno], or a error
Here as well.

> copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,..)
> 
> Reported-by: Wenliang Fan <fanwlexca@gmail.com>
> Suggested-by: Qixue Xiao <xiaoqixue_1@163.com>
> Signed-off-by: Yu Chen <chyyuu@gmail.com>
Reviewed-by: Levente Kurusa <levex@linux.com>

(Once you have fixed my suggestions :-) )

> ---
>  drivers/scsi/megaraid.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
> index 41bbc21..0b90c54 100644
> --- a/drivers/scsi/megaraid.c
> +++ b/drivers/scsi/megaraid.c
> @@ -3099,7 +3099,10 @@ megadev_ioctl(struct file *filep, unsigned int
> cmd, unsigned long arg)
>   /*
>   * Which adapter
>   */
> - if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
> + adapno = GETADAP(uioc.adapno);
> + if( adapno < 0 )
> + return (-EINVAL);
> + if( adapno >= hba_count )
>   return (-ENODEV);
> 
>   if( copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,


Total whitespace damage. :-)

Try sending them with 'git send-email' or configure your email client
properly.

Oh, and one last thing. Don't post the v3 as a reply to this, but
instead as a whole new post.

-- 
Regards,
Levente Kurusa

Re: [PATCH] scsi: integer overflow in megadev_ioctl()

[Yu Chen]

Thank you!  The new patch
-------------------------------------------------------------
[PATCH] scsi: integer overflow in megadev_ioctl()

There is a potential integer overflow in megadev_ioctl() if
userspace passes in a large u32 variable uioc.adapno.
Theint variable adapno would < 0, leading to a error
array access for hdb_soft_state[adapno], or a error
copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,..)

Reported-by: Wenliang Fan <fanwlexca@gmail.com>
Suggested-by: Qixue Xiao <xiaoqixue_1@163.com>
Signed-off-by: Yu Chen <chyyuu@gmail.com>
---
 drivers/scsi/megaraid.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index 41bbc21..0b90c54 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -3099,7 +3099,10 @@ megadev_ioctl(struct file *filep, unsigned int
cmd, unsigned long arg)
  /*
  * Which adapter
  */
- if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
+ adapno = GETADAP(uioc.adapno);
+ if( adapno < 0 )
+ return (-EINVAL);
+ if( adapno >= hba_count )
  return (-ENODEV);

  if( copy_to_user(uioc.uioc_uaddr, mcontroller+adapno,
@@ -3113,8 +3116,10 @@ megadev_ioctl(struct file *filep, unsigned int
cmd, unsigned long arg)
  /*
  * Which adapter
  */
-                adapno = GETADAP(uioc.adapno);
- if( adapno >= hba_count || adapno < 0 )
+ adapno = GETADAP(uioc.adapno);
+ if( adapno < 0 )
+ return (-EINVAL);
+ if( adapno >= hba_count )
  return (-ENODEV);

  adapter = hba_soft_state[adapno];
@@ -3161,7 +3166,10 @@ megadev_ioctl(struct file *filep, unsigned int
cmd, unsigned long arg)
  /*
  * Which adapter
  */
- if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
+ adapno = GETADAP(uioc.adapno);
+ if( adapno < 0 )
+ return (-EINVAL);
+ if( adapno >= hba_count )
  return (-ENODEV);

  adapter = hba_soft_state[adapno];
-- 
1.8.3.2

2013/12/14 Levente Kurusa <levex@linux.com>:
> Hi,
>
> On 12/13/2013 05:55 PM, Yu Chen wrote:
>>  drivers/scsi/megaraid.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
>> index 816db12..41bbc21 100644
>> --- a/drivers/scsi/megaraid.c
>> +++ b/drivers/scsi/megaraid.c
>> @@ -3113,7 +3113,8 @@ megadev_ioctl(struct file *filep, unsigned int
>> cmd, unsigned long arg)
>>   /*
>>   * Which adapter
>>   */
>> - if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
>> +                adapno = GETADAP(uioc.adapno);
>> + if( adapno >= hba_count || adapno < 0 )
>>   return (-ENODEV);
>
> Wouldn't returning -EINVAL be better? For hba_count I understand that
> -ENODEV is returned but for adapno being a passed variable, I would
> suggest returning -EINVAL.
>
> --
> Regards,
> Levente Kurusa



-- 
Best Regards
==============================================
Yu Chen
Ph.D.  Associate Professor
System Software&Software Engineering Group,
Dept. of Computer Science and Technology
Tsinghua University, Beijing 100084, P.R. China
E-Mail: mailto:yuchen@tsinghua.edu.cn  chyyuu@gmail.com
==============================================

Re: [PATCH] scsi: integer overflow in megadev_ioctl()

[Levente Kurusa]

Hi,

On 12/13/2013 05:55 PM, Yu Chen wrote:
>  drivers/scsi/megaraid.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
> index 816db12..41bbc21 100644
> --- a/drivers/scsi/megaraid.c
> +++ b/drivers/scsi/megaraid.c
> @@ -3113,7 +3113,8 @@ megadev_ioctl(struct file *filep, unsigned int
> cmd, unsigned long arg)
>   /*
>   * Which adapter
>   */
> - if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
> +                adapno = GETADAP(uioc.adapno);
> + if( adapno >= hba_count || adapno < 0 )
>   return (-ENODEV);

Wouldn't returning -EINVAL be better? For hba_count I understand that
-ENODEV is returned but for adapno being a passed variable, I would
suggest returning -EINVAL.

-- 
Regards,
Levente Kurusa

[PATCH] scsi: integer overflow in megadev_ioctl()

[Yu Chen]

There is a potential integer overflow in megadev_ioctl() if
userspace passes in a large u32 variable uioc.adapno. The
int variable adapno would < 0, leading to a error array access
for hdb_soft_state[adapno].

Reported-by: Wenliang Fan <fanwlexca@gmail.com>
Suggested-by: Qixue Xiao <xiaoqixue_1@163.com>
Signed-off-by: Yu Chen <chyyuu@gmail.com>
---
 drivers/scsi/megaraid.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index 816db12..41bbc21 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -3113,7 +3113,8 @@ megadev_ioctl(struct file *filep, unsigned int
cmd, unsigned long arg)
  /*
  * Which adapter
  */
- if( (adapno = GETADAP(uioc.adapno)) >= hba_count )
+                adapno = GETADAP(uioc.adapno);
+ if( adapno >= hba_count || adapno < 0 )
  return (-ENODEV);

  adapter = hba_soft_state[adapno];
-- 
1.8.3.2