Unverified Commit 79ef24df authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!9853 nilfs2: fix use-after-free of timer for log writer thread 

Merge Pull Request from: @ci-robot 
 
PR sync from: Guo Mengqi <guomengqi3@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/HFFVKKJPO3GWIE2ULUXJHNZ6Z6IYDEQ3/ 
 
https://gitee.com/src-openeuler/kernel/issues/IA6S5D 
 
Link:https://gitee.com/openeuler/kernel/pulls/9853

 

Reviewed-by: default avatarWeilong Chen <chenweilong@huawei.com>
Signed-off-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
parents 165a5e6b c312b264

fs/nilfs2/segment.c

+19 −6
Original line number Diff line number Diff line
@@ -2164,8 +2164,10 @@ static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 
{

	spin_lock(&sci->sc_state_lock);

	if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {

		if (sci->sc_task) {

			sci->sc_timer.expires = jiffies + sci->sc_interval;

			add_timer(&sci->sc_timer);

		}

		sci->sc_state |= NILFS_SEGCTOR_COMMIT;

	}

	spin_unlock(&sci->sc_state_lock);
@@ -2385,9 +2387,20 @@ int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, 
 */

static void nilfs_segctor_accept(struct nilfs_sc_info *sci)

{

	bool thread_is_alive;



	spin_lock(&sci->sc_state_lock);

	sci->sc_seq_accepted = sci->sc_seq_request;

	thread_is_alive = (bool)sci->sc_task;

	spin_unlock(&sci->sc_state_lock);



	/*

	 * This function does not race with the log writer thread's

	 * termination.  Therefore, deleting sc_timer, which should not be

	 * done after the log writer thread exits, can be done safely outside

	 * the area protected by sc_state_lock.

	 */

	if (thread_is_alive)

		del_timer_sync(&sci->sc_timer);

}
@@ -2414,7 +2427,7 @@ static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err) 
			sci->sc_flush_request &= ~FLUSH_DAT_BIT;



		/* re-enable timer if checkpoint creation was not done */

		if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&

		if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && sci->sc_task &&

		    time_before(jiffies, sci->sc_timer.expires))

			add_timer(&sci->sc_timer);

	}
@@ -2604,6 +2617,7 @@ static int nilfs_segctor_thread(void *arg) 
	int timeout = 0;



	sci->sc_timer_task = current;

	timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);



	/* start sync. */

	sci->sc_task = current;
@@ -2670,6 +2684,7 @@ static int nilfs_segctor_thread(void *arg) 
 end_thread:

	/* end sync. */

	sci->sc_task = NULL;

	del_timer_sync(&sci->sc_timer);

	wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */

	spin_unlock(&sci->sc_state_lock);

	return 0;
@@ -2733,7 +2748,6 @@ static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb, 
	INIT_LIST_HEAD(&sci->sc_gc_inodes);

	INIT_LIST_HEAD(&sci->sc_iput_queue);

	INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);

	timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);



	sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;

	sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
@@ -2819,7 +2833,6 @@ static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 


	down_write(&nilfs->ns_segctor_sem);



	del_timer_sync(&sci->sc_timer);

	kfree(sci);

}