[Skiboot] [PATCH v2 4/6] core/pci: pci_slot_add_loc use NUL terminated strings

[Vasant Hegde]

On 05/02/2019 04:45 PM, Nicholas Piggin wrote:
> Use NUL terminated strings consistently, making the maximum string
> length in all cases the same, and avoiding dt_add_property_nstr.
> 
> This avoids the following warning that appears after adding more
> checking to string ops:
> 
>    core/pci-slot.c: In function ‘pci_slot_add_loc’:
>    skiboot/libc/include/string.h:19:17: warning: ‘__builtin_strncpy’
>      specified bound 80 equals destination size [-Wstringop-truncation]
>     #define strncpy __builtin_strncpy
>    core/pci-slot.c:244:3: note: in expansion of macro ‘strncpy’
>       strncpy(loc_code, label, sizeof(loc_code));
>       ^~~~~~~
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> ---
>   core/pci-slot.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/core/pci-slot.c b/core/pci-slot.c
> index 497d0a47f..54f25befe 100644
> --- a/core/pci-slot.c
> +++ b/core/pci-slot.c
> @@ -222,7 +222,7 @@ struct pci_slot *pci_slot_find(uint64_t id)
>   void pci_slot_add_loc(struct pci_slot *slot,
>   			struct dt_node *np, const char *label)
>   {
> -	char tmp[8], loc_code[LOC_CODE_SIZE];
> +	char tmp[8], loc_code[LOC_CODE_SIZE + 1];

As spec, Location code size is 80 char including NULL character.
So we dont need above change. Instead we should fix our strncpy() code (below hunk).

-Vasant