When deciding whether to call the stop hook of a plugin instance, only two things are relevant: If the plugin actually has a stop hook defined, and if the plugin instance is still used in a different stack. The private data of a plugin instance is opaque to ulogd, so its size or content are irrelevant to the stop-hook decision. And in the same vein should ulogd never write to it. The one-null-byte write could previously lead to an out-of-bounds write on plugins with a stop hook and zero-size private data. Signed-off-by: Corubba Smith <corubba@xxxxxx> --- src/ulogd.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/src/ulogd.c b/src/ulogd.c index 6c5ff9a..9a0060d 100644 --- a/src/ulogd.c +++ b/src/ulogd.c @@ -1327,12 +1327,10 @@ static void stop_pluginstances() llist_for_each_entry(stack, &ulogd_pi_stacks, stack_list) { llist_for_each_entry_safe(pi, npi, &stack->list, list) { - if ((pi->plugin->priv_size > 0 || *pi->plugin->stop) && - pluginstance_stop(pi)) { + if (*pi->plugin->stop && pluginstance_stop(pi)) { ulogd_log(ULOGD_DEBUG, "calling stop for %s\n", pi->plugin->name); (*pi->plugin->stop)(pi); - pi->private[0] = 0; } /* NB: plugin->stop() might access other plugin instances, -- 2.48.1