From: Martin Wilck <mwilck@xxxxxxxx> libdevmapper will most probably not return a UUID for non-existing maps anyway. But it's cheap to double-check here. Signed-off-by: Martin Wilck <mwilck@xxxxxxxx> Reviewed-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx> --- libmultipath/devmapper.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c index 248c373..9be82f4 100644 --- a/libmultipath/devmapper.c +++ b/libmultipath/devmapper.c @@ -706,12 +706,16 @@ dm_get_prefixed_uuid(const char *name, char *uuid, int uuid_len) { struct dm_task *dmt; const char *uuidtmp; + struct dm_info info; int r = 1; dmt = libmp_dm_task_create(DM_DEVICE_INFO); if (!dmt) return 1; + if (uuid_len > 0) + uuid[0] = '\0'; + if (!dm_task_set_name (dmt, name)) goto uuidout; @@ -720,11 +724,13 @@ dm_get_prefixed_uuid(const char *name, char *uuid, int uuid_len) goto uuidout; } + if (!dm_task_get_info(dmt, &info) || + !info.exists) + goto uuidout; + uuidtmp = dm_task_get_uuid(dmt); if (uuidtmp) strlcpy(uuid, uuidtmp, uuid_len); - else - uuid[0] = '\0'; r = 0; uuidout: -- 2.42.0 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel