Would it make more sense to actually check for failure on allocation
rather than try to remember to deal with it later? How about we just
have audit_log_kern_module return an error and fail if we are OOM?
(also this seems like a good place to use kstrdup, instead of
kmalloc+strcpy)

On Tue, 2018-07-24 at 13:57 +0800, Yi Wang wrote:
> The variable 'context->module.name' may be null pointer when
> kmalloc return null, so it's better to check it before using
> to avoid null dereference.
> 
> Signed-off-by: Yi Wang <[email protected]>
> Reviewed-by: Jiang Biao <[email protected]>
> ---
>  kernel/auditsc.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index e80459f..4830b83 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -1272,8 +1272,12 @@ static void show_special(struct audit_context
> *context, int *call_panic)
>               break;
>       case AUDIT_KERN_MODULE:
>               audit_log_format(ab, "name=");
> -             audit_log_untrustedstring(ab, context->module.name);
> -             kfree(context->module.name);
> +             if (context->module.name) {
> +                     audit_log_untrustedstring(ab, context-
> >module.name);
> +                     kfree(context->module.name);
> +             } else
> +                     audit_log_format(ab, "(null)");
> +
>               break;
>       }
>       audit_log_end(ab);
> @@ -2409,7 +2413,8 @@ void __audit_log_kern_module(char *name)
>       struct audit_context *context = current->audit_context;
>  
>       context->module.name = kmalloc(strlen(name) + 1, GFP_KERNEL);
> -     strcpy(context->module.name, name);
> +     if (context->module.name)
> +             strcpy(context->module.name, name);
>       context->type = AUDIT_KERN_MODULE;
>  }
>  

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