From 43efdc8f0e6d7088ec61bd55a73bf853f002d043 Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Mon, 11 Nov 2019 10:03:54 +0100 Subject: pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In the old code (e.g.) mutex_destroy() was called before pwmchip_remove(). Between these two calls it is possible that a PWM callback is used which tries to grab the mutex. Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding --- drivers/pwm/pwm-omap-dmtimer.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers/pwm/pwm-omap-dmtimer.c') diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c index 00772fc53490..bdf94c78655f 100644 --- a/drivers/pwm/pwm-omap-dmtimer.c +++ b/drivers/pwm/pwm-omap-dmtimer.c @@ -351,6 +351,11 @@ put: static int pwm_omap_dmtimer_remove(struct platform_device *pdev) { struct pwm_omap_dmtimer_chip *omap = platform_get_drvdata(pdev); + int ret; + + ret = pwmchip_remove(&omap->chip); + if (ret) + return ret; if (pm_runtime_active(&omap->dm_timer_pdev->dev)) omap->pdata->stop(omap->dm_timer); @@ -359,7 +364,7 @@ static int pwm_omap_dmtimer_remove(struct platform_device *pdev) mutex_destroy(&omap->mutex); - return pwmchip_remove(&omap->chip); + return 0; } static const struct of_device_id pwm_omap_dmtimer_of_match[] = { -- cgit From c4cf7aa57eb83b108d2d9c6c37c143388fee2a4d Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Mon, 11 Nov 2019 10:03:55 +0100 Subject: pwm: omap-dmtimer: Simplify error handling MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Instead of doing error handling in the middle of ->probe(), move error handling and freeing the reference to timer to the end. This fixes a resource leak as dm_timer wasn't freed when allocating *omap failed. Implementation note: The put: label was never reached without a goto and ret being unequal to 0, so the removed return statement is fine. Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding --- drivers/pwm/pwm-omap-dmtimer.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) (limited to 'drivers/pwm/pwm-omap-dmtimer.c') diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c index bdf94c78655f..e36fcad668a6 100644 --- a/drivers/pwm/pwm-omap-dmtimer.c +++ b/drivers/pwm/pwm-omap-dmtimer.c @@ -298,15 +298,10 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev) goto put; } -put: - of_node_put(timer); - if (ret < 0) - return ret; - omap = devm_kzalloc(&pdev->dev, sizeof(*omap), GFP_KERNEL); if (!omap) { - pdata->free(dm_timer); - return -ENOMEM; + ret = -ENOMEM; + goto err_alloc_omap; } omap->pdata = pdata; @@ -339,13 +334,28 @@ put: ret = pwmchip_add(&omap->chip); if (ret < 0) { dev_err(&pdev->dev, "failed to register PWM\n"); - omap->pdata->free(omap->dm_timer); - return ret; + goto err_pwmchip_add; } + of_node_put(timer); + platform_set_drvdata(pdev, omap); return 0; + +err_pwmchip_add: + + /* + * *omap is allocated using devm_kzalloc, + * so no free necessary here + */ +err_alloc_omap: + + pdata->free(dm_timer); +put: + of_node_put(timer); + + return ret; } static int pwm_omap_dmtimer_remove(struct platform_device *pdev) -- cgit From c7cb3a1dd53f63c64fb2b567d0be130b92a44d91 Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Mon, 11 Nov 2019 10:03:56 +0100 Subject: pwm: omap-dmtimer: put_device() after of_find_device_by_node() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This was found by coccicheck: drivers/pwm/pwm-omap-dmtimer.c:304:2-8: ERROR: missing put_device; call of_find_device_by_node on line 255, but without a corresponding object release within this function. Reported-by: Markus Elfring Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding --- drivers/pwm/pwm-omap-dmtimer.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) (limited to 'drivers/pwm/pwm-omap-dmtimer.c') diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c index e36fcad668a6..88a3c5690fea 100644 --- a/drivers/pwm/pwm-omap-dmtimer.c +++ b/drivers/pwm/pwm-omap-dmtimer.c @@ -256,7 +256,7 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev) if (!timer_pdev) { dev_err(&pdev->dev, "Unable to find Timer pdev\n"); ret = -ENODEV; - goto put; + goto err_find_timer_pdev; } timer_pdata = dev_get_platdata(&timer_pdev->dev); @@ -264,7 +264,7 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev) dev_dbg(&pdev->dev, "dmtimer pdata structure NULL, deferring probe\n"); ret = -EPROBE_DEFER; - goto put; + goto err_platdata; } pdata = timer_pdata->timer_ops; @@ -283,19 +283,19 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev) !pdata->write_counter) { dev_err(&pdev->dev, "Incomplete dmtimer pdata structure\n"); ret = -EINVAL; - goto put; + goto err_platdata; } if (!of_get_property(timer, "ti,timer-pwm", NULL)) { dev_err(&pdev->dev, "Missing ti,timer-pwm capability\n"); ret = -ENODEV; - goto put; + goto err_timer_property; } dm_timer = pdata->request_by_node(timer); if (!dm_timer) { ret = -EPROBE_DEFER; - goto put; + goto err_request_timer; } omap = devm_kzalloc(&pdev->dev, sizeof(*omap), GFP_KERNEL); @@ -352,7 +352,14 @@ err_pwmchip_add: err_alloc_omap: pdata->free(dm_timer); -put: +err_request_timer: + +err_timer_property: +err_platdata: + + put_device(&timer_pdev->dev); +err_find_timer_pdev: + of_node_put(timer); return ret; @@ -372,6 +379,8 @@ static int pwm_omap_dmtimer_remove(struct platform_device *pdev) omap->pdata->free(omap->dm_timer); + put_device(&omap->dm_timer_pdev->dev); + mutex_destroy(&omap->mutex); return 0; -- cgit