[PATCH v2] powerpc/powernv: Restrict OPAL symbol map to only be readable by root

[Andrew Donnellan]

On 3/5/19 5:52 pm, Andrew Donnellan wrote:
> Currently the OPAL symbol map is globally readable, which seems bad as it
> contains physical addresses.
> 
> Restrict it to root.
> 
> Suggested-by: Michael Ellerman <mpe at ellerman.id.au>
> Cc: Jordan Niethe <jniethe5 at gmail.com>
> Cc: Stewart Smith <stewart at linux.ibm.com>
> Fixes: c8742f85125d ("powerpc/powernv: Expose OPAL firmware symbol map")
> Cc: stable at vger.kernel.org
> Signed-off-by: Andrew Donnellan <ajd at linux.ibm.com>

mpe: ping?

> 
> ---
> 
> v1->v2:
> 
> - fix tabs vs spaces (Greg)
> ---
>   arch/powerpc/platforms/powernv/opal.c | 11 +++++++----
>   1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
> index 2b0eca104f86..0582a02623d0 100644
> --- a/arch/powerpc/platforms/powernv/opal.c
> +++ b/arch/powerpc/platforms/powernv/opal.c
> @@ -681,7 +681,10 @@ static ssize_t symbol_map_read(struct file *fp, struct kobject *kobj,
>   				       bin_attr->size);
>   }
>   
> -static BIN_ATTR_RO(symbol_map, 0);
> +static struct bin_attribute symbol_map_attr = {
> +	.attr = {.name = "symbol_map", .mode = 0400},
> +	.read = symbol_map_read
> +};
>   
>   static void opal_export_symmap(void)
>   {
> @@ -698,10 +701,10 @@ static void opal_export_symmap(void)
>   		return;
>   
>   	/* Setup attributes */
> -	bin_attr_symbol_map.private = __va(be64_to_cpu(syms[0]));
> -	bin_attr_symbol_map.size = be64_to_cpu(syms[1]);
> +	symbol_map_attr.private = __va(be64_to_cpu(syms[0]));
> +	symbol_map_attr.size = be64_to_cpu(syms[1]);
>   
> -	rc = sysfs_create_bin_file(opal_kobj, &bin_attr_symbol_map);
> +	rc = sysfs_create_bin_file(opal_kobj, &symbol_map_attr);
>   	if (rc)
>   		pr_warn("Error %d creating OPAL symbols file\n", rc);
>   }
> 

-- 
Andrew Donnellan              OzLabs, ADL Canberra
ajd at linux.ibm.com             IBM Australia Limited