On Tue, Jul 09, 2024 at 11:39:12PM +0200, Martin Wilck wrote:
> Use sscanf to make the parsing of the UUID more robust.
>
> Signed-off-by: Martin Wilck <mwilck@xxxxxxxx>
> ---
> libmultipath/devmapper.c | 17 +++++++----------
> 1 file changed, 7 insertions(+), 10 deletions(-)
>
> diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c
> index 56157af..d62a7dd 100644
> --- a/libmultipath/devmapper.c
> +++ b/libmultipath/devmapper.c
> @@ -846,23 +846,20 @@ int dm_get_uuid(const char *name, char *uuid, int uuid_len)
>
> static int is_mpath_part(const char *part_name, const char *map_name)
> {
> - char *p;
> - char part_uuid[DM_UUID_LEN], map_uuid[DM_UUID_LEN];
> + char part_uuid[DM_UUID_LEN], map_uuid[DM_UUID_LEN], c;
> + int np, nc;
>
> if (dm_get_dm_uuid(part_name, part_uuid) != DMP_OK)
> return 0;
>
> + if (2 != sscanf(part_uuid, "part%d-%n" UUID_PREFIX "%c", &np, &nc, &c)
we should probably use "part%u-%n" so we can't match a "-" before the
number.
-Ben
> + || np <= 0)
> + return 0;
> +
> if (dm_get_dm_uuid(map_name, map_uuid) != DMP_OK)
> return 0;
>
> - if (strncmp(part_uuid, "part", 4) != 0)
> - return 0;
> -
> - p = strstr(part_uuid, UUID_PREFIX);
> - if (p && !strcmp(p, map_uuid))
> - return 1;
> -
> - return 0;
> + return !strcmp(part_uuid + nc, map_uuid);
> }
>
> int dm_get_status(const char *name, char **outstatus)
> --
> 2.45.2
