Re: [PATCH] fs:Fix kmemleak leak warning in getname_flags about working on unitialized memory

[Tetsuo Handa]

On 2016/08/04 6:48, Nicholas Krause wrote:
> This fixes a kmemleak leak warning complaining about working on
> unitializied memory as found in the function, getname_flages. Seems
> that we are indeed working on unitialized memory, as the filename
> char pointer is never made to point to the filname structure's result
> member for holding it's name, fix this by using memcpy to copy the
> filname structure pointer's, name to the char pointer passed to this
> function.
> 
> Signed-off-by: Nicholas Krause <xerofo...@gmail.com>
> ---
>  fs/namei.c         | 1 +
>  mm/early_ioremap.c | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/fs/namei.c b/fs/namei.c
> index c386a32..6b18d57 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -196,6 +196,7 @@ getname_flags(const char __user *filename, int flags, int 
> *empty)
>               }
>       }
>  
> +     memcpy((char *)result->name, filename, len);

This filename is a __user pointer. Reading with memcpy() is not safe.

>       result->uptr = filename;
>       result->aname = NULL;
>       audit_getname(result);