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

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From	James Hogan <james.hogan@imgtec.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] MIPS: KASLR: Fix handling of NULL FDT
Date	Mon, 17 Oct 2016 12:20:01 +0200
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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: <stable@vger.kernel.org> # 4.7+
> Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
> ---
> 
>  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
> 
>

Thread

[PATCH] MIPS: KASLR: Fix handling of NULL FDT Matt Redfearn <matt.redfearn@imgtec.com> - 2016-10-17 12:10 +0200
  Re: [PATCH] MIPS: KASLR: Fix handling of NULL FDT James Hogan <james.hogan@imgtec.com> - 2016-10-17 12:20 +0200
  Re: [PATCH] MIPS: KASLR: Fix handling of NULL FDT Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> - 2016-10-17 15:50 +0200

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