Re: [PATCH] MIPS: KASLR: Fix handling of NULL FDT

2016-10-17 Thread Sergei Shtylyov

Hello.

On 10/17/2016 01:04 PM, Matt Redfearn wrote:


If platform code returns a NULL pointer to the FDT, initial_boot_params
will not get set to a valid pointer and attempting to find the /chosen
node in it will cause a NULL pointer dereference and the kernel to crash
immediately on startup - with no output to the console.

Fix this by checking that initial_boot_params is valid before using it.

Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
Cc:  # 4.7+
Signed-off-by: Matt Redfearn 
---

 arch/mips/kernel/relocate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
index ca1cc30c0891..8810183840ca 100644
--- a/arch/mips/kernel/relocate.c
+++ b/arch/mips/kernel/relocate.c
@@ -200,6 +200,7 @@ static inline __init unsigned long get_random_boot(void)

 #if defined(CONFIG_USE_OF)
/* Get any additional entropy passed in device tree */
+   if (initial_boot_params)
{


   CodingStyle: *if* and { should be on the same line.

[...]

MBR, Sergei



Re: [PATCH] MIPS: KASLR: Fix handling of NULL FDT

2016-10-17 Thread Sergei Shtylyov

Hello.

On 10/17/2016 01:04 PM, Matt Redfearn wrote:


If platform code returns a NULL pointer to the FDT, initial_boot_params
will not get set to a valid pointer and attempting to find the /chosen
node in it will cause a NULL pointer dereference and the kernel to crash
immediately on startup - with no output to the console.

Fix this by checking that initial_boot_params is valid before using it.

Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
Cc:  # 4.7+
Signed-off-by: Matt Redfearn 
---

 arch/mips/kernel/relocate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
index ca1cc30c0891..8810183840ca 100644
--- a/arch/mips/kernel/relocate.c
+++ b/arch/mips/kernel/relocate.c
@@ -200,6 +200,7 @@ static inline __init unsigned long get_random_boot(void)

 #if defined(CONFIG_USE_OF)
/* Get any additional entropy passed in device tree */
+   if (initial_boot_params)
{


   CodingStyle: *if* and { should be on the same line.

[...]

MBR, Sergei



Re: [PATCH] MIPS: KASLR: Fix handling of NULL FDT

2016-10-17 Thread James Hogan
Hi Matt,

On Mon, Oct 17, 2016 at 11:04:54AM +0100, Matt Redfearn wrote:
> If platform code returns a NULL pointer to the FDT, initial_boot_params
> will not get set to a valid pointer and attempting to find the /chosen
> node in it will cause a NULL pointer dereference and the kernel to crash
> immediately on startup - with no output to the console.
> 
> Fix this by checking that initial_boot_params is valid before using it.
> 
> Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
> Cc:  # 4.7+
> Signed-off-by: Matt Redfearn 
> ---
> 
>  arch/mips/kernel/relocate.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
> index ca1cc30c0891..8810183840ca 100644
> --- a/arch/mips/kernel/relocate.c
> +++ b/arch/mips/kernel/relocate.c
> @@ -200,6 +200,7 @@ static inline __init unsigned long get_random_boot(void)
>  
>  #if defined(CONFIG_USE_OF)
>   /* Get any additional entropy passed in device tree */
> + if (initial_boot_params)
>   {

The open brace should be on the same line as the if really.

Cheers
James

>   int node, len;
>   u64 *prop;
> -- 
> 2.7.4
> 
> 


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Description: Digital signature


Re: [PATCH] MIPS: KASLR: Fix handling of NULL FDT

2016-10-17 Thread James Hogan
Hi Matt,

On Mon, Oct 17, 2016 at 11:04:54AM +0100, Matt Redfearn wrote:
> If platform code returns a NULL pointer to the FDT, initial_boot_params
> will not get set to a valid pointer and attempting to find the /chosen
> node in it will cause a NULL pointer dereference and the kernel to crash
> immediately on startup - with no output to the console.
> 
> Fix this by checking that initial_boot_params is valid before using it.
> 
> Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
> Cc:  # 4.7+
> Signed-off-by: Matt Redfearn 
> ---
> 
>  arch/mips/kernel/relocate.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
> index ca1cc30c0891..8810183840ca 100644
> --- a/arch/mips/kernel/relocate.c
> +++ b/arch/mips/kernel/relocate.c
> @@ -200,6 +200,7 @@ static inline __init unsigned long get_random_boot(void)
>  
>  #if defined(CONFIG_USE_OF)
>   /* Get any additional entropy passed in device tree */
> + if (initial_boot_params)
>   {

The open brace should be on the same line as the if really.

Cheers
James

>   int node, len;
>   u64 *prop;
> -- 
> 2.7.4
> 
> 


signature.asc
Description: Digital signature


[PATCH] MIPS: KASLR: Fix handling of NULL FDT

2016-10-17 Thread Matt Redfearn
If platform code returns a NULL pointer to the FDT, initial_boot_params
will not get set to a valid pointer and attempting to find the /chosen
node in it will cause a NULL pointer dereference and the kernel to crash
immediately on startup - with no output to the console.

Fix this by checking that initial_boot_params is valid before using it.

Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
Cc:  # 4.7+
Signed-off-by: Matt Redfearn 
---

 arch/mips/kernel/relocate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
index ca1cc30c0891..8810183840ca 100644
--- a/arch/mips/kernel/relocate.c
+++ b/arch/mips/kernel/relocate.c
@@ -200,6 +200,7 @@ static inline __init unsigned long get_random_boot(void)
 
 #if defined(CONFIG_USE_OF)
/* Get any additional entropy passed in device tree */
+   if (initial_boot_params)
{
int node, len;
u64 *prop;
-- 
2.7.4



[PATCH] MIPS: KASLR: Fix handling of NULL FDT

2016-10-17 Thread Matt Redfearn
If platform code returns a NULL pointer to the FDT, initial_boot_params
will not get set to a valid pointer and attempting to find the /chosen
node in it will cause a NULL pointer dereference and the kernel to crash
immediately on startup - with no output to the console.

Fix this by checking that initial_boot_params is valid before using it.

Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
Cc:  # 4.7+
Signed-off-by: Matt Redfearn 
---

 arch/mips/kernel/relocate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
index ca1cc30c0891..8810183840ca 100644
--- a/arch/mips/kernel/relocate.c
+++ b/arch/mips/kernel/relocate.c
@@ -200,6 +200,7 @@ static inline __init unsigned long get_random_boot(void)
 
 #if defined(CONFIG_USE_OF)
/* Get any additional entropy passed in device tree */
+   if (initial_boot_params)
{
int node, len;
u64 *prop;
-- 
2.7.4