From 0b75f2dfa2a67012ff6996b322117e1d7e45abe1 Mon Sep 17 00:00:00 2001 From: Jesper Juhl Date: Sat, 11 Aug 2007 10:29:59 +0100 Subject: [PATCH] backlight: Fix cr_bllcd allocations and error paths After fixing the too small memory allocation in cr_backlight_probe() from drivers/video/backlight/cr_bllcd.c (commit e3bbb3f05339de438faf54124f25c92e6fe4ac2e) I noticed that the Coverity checker also thought there were a few memory leaks in there. I took a closer look and confirmed that there were indeed several leaks. At the start of the function we allocate storage for a 'struct cr_panel' and store the pointer in a variable named 'crp'. Then we call pci_get_device() and pci_read_config_byte() and if either of them fail we return without freeing the memory allocated for the 'struct cr_panel'. These two leaks are easy to fix since we don't even use 'crp' for anything up to this point, so I simply moved the allocation further down in the function so it only happens just before we actually need it. A bit further down we call backlight_device_register() and store the result in 'crp->cr_backlight_device'. In case of error we return 'crp->cr_backlight_device' from the function, thus leaking 'crp' itself. The same thing happens with the call to lcd_device_register(). To fix these two leaks I declare two new pointers to hold the return values, so that in case of error we can return the pointer (as before) but without leaking 'crp'. This version of the patch also adds missing backlight_device_unregister() / lcd_device_unregister() / pci_dev_put() calls to error paths. Thanks to Richard Purdie for noticing. Signed-off-by: Jesper Juhl Signed-off-by: Andrew Morton Signed-off-by: Richard Purdie --- drivers/video/backlight/cr_bllcd.c | 35 +++++++++++++++++------------- 1 file changed, 20 insertions(+), 15 deletions(-) diff --git a/drivers/video/backlight/cr_bllcd.c b/drivers/video/backlight/cr_bllcd.c index b7904da51b..92e201e81f 100644 --- a/drivers/video/backlight/cr_bllcd.c +++ b/drivers/video/backlight/cr_bllcd.c @@ -171,13 +171,11 @@ static struct lcd_ops cr_lcd_ops = { static int cr_backlight_probe(struct platform_device *pdev) { + struct backlight_device *bdp; + struct lcd_device *ldp; struct cr_panel *crp; u8 dev_en; - crp = kzalloc(sizeof(*crp), GFP_KERNEL); - if (crp == NULL) - return -ENOMEM; - lpc_dev = pci_get_device(PCI_VENDOR_ID_INTEL, CRVML_DEVICE_LPC, NULL); if (!lpc_dev) { @@ -193,27 +191,34 @@ static int cr_backlight_probe(struct platform_device *pdev) return -ENODEV; } - crp->cr_backlight_device = backlight_device_register("cr-backlight", - &pdev->dev, NULL, - &cr_backlight_ops); - if (IS_ERR(crp->cr_backlight_device)) { + bdp = backlight_device_register("cr-backlight", + &pdev->dev, NULL, &cr_backlight_ops); + if (IS_ERR(bdp)) { pci_dev_put(lpc_dev); - return PTR_ERR(crp->cr_backlight_device); + return PTR_ERR(bdp); } - crp->cr_lcd_device = lcd_device_register("cr-lcd", - &pdev->dev, NULL, - &cr_lcd_ops); - - if (IS_ERR(crp->cr_lcd_device)) { + ldp = lcd_device_register("cr-lcd", &pdev->dev, NULL, &cr_lcd_ops); + if (IS_ERR(ldp)) { + backlight_device_unregister(bdp); pci_dev_put(lpc_dev); - return PTR_ERR(crp->cr_backlight_device); + return PTR_ERR(bdp); } pci_read_config_dword(lpc_dev, CRVML_REG_GPIOBAR, &gpio_bar); gpio_bar &= ~0x3F; + crp = kzalloc(sizeof(*crp), GFP_KERNEL); + if (!crp) { + lcd_device_unregister(ldp); + backlight_device_unregister(bdp); + pci_dev_put(lpc_dev); + return -ENOMEM; + } + + crp->cr_backlight_device = bdp; + crp->cr_lcd_device = ldp; crp->cr_backlight_device->props.power = FB_BLANK_UNBLANK; crp->cr_backlight_device->props.brightness = 0; crp->cr_backlight_device->props.max_brightness = 0; -- 2.39.5