Re: [PATCH v3] tools/libs/stat: fix broken build

[Bertrand Marquis <Bertrand.Marquis@xxxxxxx>]

> On 12 Sep 2020, at 14:08, Juergen Gross <jgross@xxxxxxxx> wrote:
> 
> Making getBridge() static triggered a build error with some gcc versions:
> 
> error: 'strncpy' output may be truncated copying 15 bytes from a string of
> length 255 [-Werror=stringop-truncation]
> 
> Fix that by using a buffer with 256 bytes instead.
> 
> Fixes: 6d0ec053907794 ("tools: split libxenstat into new tools/libs/stat 
> directory")
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>

> ---
> tools/libs/stat/xenstat_linux.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/libs/stat/xenstat_linux.c b/tools/libs/stat/xenstat_linux.c
> index 793263f2b6..d2ee6fda64 100644
> --- a/tools/libs/stat/xenstat_linux.c
> +++ b/tools/libs/stat/xenstat_linux.c
> @@ -78,7 +78,7 @@ static void getBridge(char *excludeName, char *result, 
> size_t resultLen)
>                               sprintf(tmp, "/sys/class/net/%s/bridge", 
> de->d_name);
> 
>                               if (access(tmp, F_OK) == 0) {
> -                                     strncpy(result, de->d_name, resultLen - 
> 1);
> +                                     strncpy(result, de->d_name, resultLen);
>                                       result[resultLen - 1] = 0;
>                               }
>               }
> @@ -264,7 +264,7 @@ int xenstat_collect_networks(xenstat_node * node)
> {
>       /* Helper variables for parseNetDevLine() function defined above */
>       int i;
> -     char line[512] = { 0 }, iface[16] = { 0 }, devBridge[16] = { 0 }, 
> devNoBridge[17] = { 0 };
> +     char line[512] = { 0 }, iface[16] = { 0 }, devBridge[256] = { 0 }, 
> devNoBridge[257] = { 0 };
>       unsigned long long rxBytes, rxPackets, rxErrs, rxDrops, txBytes, 
> txPackets, txErrs, txDrops;
> 
>       struct priv_data *priv = get_priv_data(node->handle);
> -- 
> 2.26.2
> 
>