From a7abda8d721359363d679c5f2de964f29419568c Mon Sep 17 00:00:00 2001 From: minskey guo Date: Fri, 17 Sep 2010 14:03:27 +0800 Subject: [PATCH] NULL pointer might be used in ips_monitor() The patch is to create ips_adjust thread before ips_monitor begins to run because the latter will kthread_stop() or wake up the former via ips->adjust pointer. Without this change, it is possible that ips->adjust is NULL when kthread_stop() or wake_up_process() is called in ips_monitor(). Signed-off-by: minskey guo Acked-by: Jesse Barnes Signed-off-by: Matthew Garrett --- drivers/platform/x86/intel_ips.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/platform/x86/intel_ips.c b/drivers/platform/x86/intel_ips.c index 71dcc410f9d0..bfa9c726054a 100644 --- a/drivers/platform/x86/intel_ips.c +++ b/drivers/platform/x86/intel_ips.c @@ -940,7 +940,6 @@ static int ips_monitor(void *data) kfree(mch_samples); kfree(cpu_samples); kfree(mchp_samples); - kthread_stop(ips->adjust); return -ENOMEM; } @@ -1535,19 +1534,24 @@ static int ips_probe(struct pci_dev *dev, const struct pci_device_id *id) ips_enable_cpu_turbo(ips); ips->cpu_turbo_enabled = true; - /* Set up the work queue and monitor/adjust threads */ - ips->monitor = kthread_run(ips_monitor, ips, "ips-monitor"); - if (IS_ERR(ips->monitor)) { + /* Create thermal adjust thread */ + ips->adjust = kthread_create(ips_adjust, ips, "ips-adjust"); + if (IS_ERR(ips->adjust)) { dev_err(&dev->dev, - "failed to create thermal monitor thread, aborting\n"); + "failed to create thermal adjust thread, aborting\n"); ret = -ENOMEM; goto error_free_irq; + } - ips->adjust = kthread_create(ips_adjust, ips, "ips-adjust"); - if (IS_ERR(ips->adjust)) { + /* + * Set up the work queue and monitor thread. The monitor thread + * will wake up ips_adjust thread. + */ + ips->monitor = kthread_run(ips_monitor, ips, "ips-monitor"); + if (IS_ERR(ips->monitor)) { dev_err(&dev->dev, - "failed to create thermal adjust thread, aborting\n"); + "failed to create thermal monitor thread, aborting\n"); ret = -ENOMEM; goto error_thread_cleanup; } @@ -1566,7 +1570,7 @@ static int ips_probe(struct pci_dev *dev, const struct pci_device_id *id) return ret; error_thread_cleanup: - kthread_stop(ips->monitor); + kthread_stop(ips->adjust); error_free_irq: free_irq(ips->dev->irq, ips); error_unmap: -- 2.20.1