Re: [PATCH 3/8] conf: Fix not-actually-const parameter to conf_runas() and conf_ugid()

[Laurent Vivier <lvivier@redhat.com>]

On 5/11/26 12:03, David Gibson wrote:
> Commit 4af3d83170fd changed the @opt parameter to conf_runas() to a const
> pointer, to remove a cppcheck error.  However, that error was a false
> positive.  We *do* modify that parameter via an aliased pointer within it
> retreived from strchr().  At least with gcc 16.1.1 that now causes a
> "discards const" warning.  Revert that change and instead directly suppress
> the cppcheck warning.
> 
> Fixes: 4af3d83170fd ("treewide: Fix more pointers which can be const")
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Reviewed-by: Laurent Vivier <lvivier@redhat.com>

> ---
>   conf.c | 7 ++++---
>   1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/conf.c b/conf.c
> index 4a4ab489..8acf66cc 100644
> --- a/conf.c
> +++ b/conf.c
> @@ -925,7 +925,8 @@ dns6:
>    *
>    * Return: 0 on success, negative error code on failure
>    */
> -static int conf_runas(const char *opt, unsigned int *uid, unsigned int *gid)
> +/* cppcheck-suppress [constParameterPointer,unmatchedSuppression] */
> +static int conf_runas(char *opt, unsigned int *uid, unsigned int *gid)
>   {
>   	const char *uopt, *gopt = NULL;
>   	char *sep = strchr(opt, ':');
> @@ -977,7 +978,7 @@ static int conf_runas(const char *opt, unsigned int *uid, unsigned int *gid)
>    * @uid:	User ID, set on success
>    * @gid:	Group ID, set on success
>    */
> -static void conf_ugid(const char *runas, uid_t *uid, gid_t *gid)
> +static void conf_ugid(char *runas, uid_t *uid, gid_t *gid)
>   {
>   	/* If user has specified --runas, that takes precedence... */
>   	if (runas) {
> @@ -1247,7 +1248,7 @@ void conf(struct ctx *c, int argc, char **argv)
>   	uint8_t prefix_len_from_opt = 0;
>   	unsigned int ifi4 = 0, ifi6 = 0;
>   	const char *logfile = NULL;
> -	const char *runas = NULL;
> +	char *runas = NULL;
>   	size_t logsize = 0;
>   	long fd_tap_opt;
>   	int name, ret;