diff options
Diffstat (limited to 'kernel/livepatch/transition.c')
| -rw-r--r-- | kernel/livepatch/transition.c | 37 |
1 files changed, 34 insertions, 3 deletions
diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c index 428533ec51b5..0ab7abd53b0b 100644 --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -59,6 +59,7 @@ static void klp_complete_transition(void) struct klp_func *func; struct task_struct *g, *task; unsigned int cpu; + bool immediate_func = false; if (klp_target_state == KLP_UNPATCHED) { /* @@ -79,9 +80,16 @@ static void klp_complete_transition(void) if (klp_transition_patch->immediate) goto done; - klp_for_each_object(klp_transition_patch, obj) - klp_for_each_func(obj, func) + klp_for_each_object(klp_transition_patch, obj) { + klp_for_each_func(obj, func) { func->transition = false; + if (func->immediate) + immediate_func = true; + } + } + + if (klp_target_state == KLP_UNPATCHED && !immediate_func) + module_put(klp_transition_patch->mod); /* Prevent klp_ftrace_handler() from seeing KLP_UNDEFINED state */ if (klp_target_state == KLP_PATCHED) @@ -113,8 +121,31 @@ done: */ void klp_cancel_transition(void) { - klp_target_state = !klp_target_state; + struct klp_patch *patch = klp_transition_patch; + struct klp_object *obj; + struct klp_func *func; + bool immediate_func = false; + + if (WARN_ON_ONCE(klp_target_state != KLP_PATCHED)) + return; + + klp_target_state = KLP_UNPATCHED; klp_complete_transition(); + + /* + * In the enable error path, even immediate patches can be safely + * removed because the transition hasn't been started yet. + * + * klp_complete_transition() doesn't have a module_put() for immediate + * patches, so do it here. + */ + klp_for_each_object(patch, obj) + klp_for_each_func(obj, func) + if (func->immediate) + immediate_func = true; + + if (patch->immediate || immediate_func) + module_put(patch->mod); } /* |