From 2a38010e6cb5f24511ab60b1c9db86ebc6a5e4bc Mon Sep 17 00:00:00 2001 From: Patrick Daly Date: Thu, 23 Oct 2014 18:01:33 -0700 Subject: nf: IDLETIMER: Fix possible use before initialization in idletimer_resume idletimer_resume() assumes that the PM_SUSPEND_PREPARE notifier is sent before PM_POST_SUSPEND so that timer->last_suspend_time is initialized. However, it is possible for PM_POST_SUSPEND to be sent first if there is an error returned from another driver's PM_SUSPEND_PREPARE notifier. Add a flag indicating whether the current value of timer->last_suspend is valid. Detected with CONFIG_SLUB_DEBUG & CONFIG_DEBUG_SPINLOCK in arm64. The timestamp lock is held for more than a minute while set_normalized_timespec() proceses the poisoned timer->last_suspend_time argument. Change-Id: I95328b0ac85dba819ff9cef751c3d07300c232f1 Signed-off-by: Patrick Daly --- net/netfilter/xt_IDLETIMER.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c index 4a2d853a90b2..dda332d821e4 100644 --- a/net/netfilter/xt_IDLETIMER.c +++ b/net/netfilter/xt_IDLETIMER.c @@ -75,6 +75,7 @@ struct idletimer_tg { bool send_nl_msg; bool active; uid_t uid; + bool suspend_time_valid; }; static LIST_HEAD(idletimer_tg_list); @@ -244,8 +245,13 @@ static int idletimer_resume(struct notifier_block *notifier, switch (pm_event) { case PM_SUSPEND_PREPARE: get_monotonic_boottime(&timer->last_suspend_time); + timer->suspend_time_valid = true; break; case PM_POST_SUSPEND: + if (!timer->suspend_time_valid) + break; + timer->suspend_time_valid = false; + spin_lock_bh(×tamp_lock); if (!timer->active) { spin_unlock_bh(×tamp_lock); @@ -280,7 +286,7 @@ static int idletimer_tg_create(struct idletimer_tg_info *info) { int ret; - info->timer = kmalloc(sizeof(*info->timer), GFP_KERNEL); + info->timer = kzalloc(sizeof(*info->timer), GFP_KERNEL); if (!info->timer) { ret = -ENOMEM; goto out; -- cgit v1.2.3