From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> Date: Sun, 7 Jan 2018 15:56:11 +0100 Up to four checks could be repeated by the ufx_usb_probe() function during error handling even if the relevant properties can be determined for the involved variables before by source code analysis. * Return directly after a call of the function "kzalloc" failed at the beginning. * Adjust jump targets so that extra checks can be omitted at the end. * Delete initialisations for the variables "info" and "retval" which became unnecessary with this refactoring. Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> --- v3: This update suggestion was rebased on source files from the software "Linux next-20180105". v2: A call of the function "fb_dealloc_cmap" was preserved for the exception handling at the end. drivers/video/fbdev/smscufx.c | 46 ++++++++++++++++++------------------------- 1 file changed, 19 insertions(+), 27 deletions(-) diff --git a/drivers/video/fbdev/smscufx.c b/drivers/video/fbdev/smscufx.c index 8db7085e5d1a..893daeb1ffd9 100644 --- a/drivers/video/fbdev/smscufx.c +++ b/drivers/video/fbdev/smscufx.c @@ -1620,8 +1620,8 @@ static int ufx_usb_probe(struct usb_interface *interface, { struct usb_device *usbdev; struct ufx_data *dev; - struct fb_info *info = NULL; - int retval = -ENOMEM; + struct fb_info *info; + int retval; u32 id_rev, fpga_rev; /* usb initialization */ @@ -1631,7 +1631,7 @@ static int ufx_usb_probe(struct usb_interface *interface, dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (dev == NULL) { dev_err(&usbdev->dev, "ufx_usb_probe: failed alloc of dev struct\n"); - goto error; + return -ENOMEM; } /* we need to wait for both usb and fbdev to spin down on disconnect */ @@ -1652,9 +1652,8 @@ static int ufx_usb_probe(struct usb_interface *interface, dev_dbg(dev->gdev, "fb_defio enable=%d\n", fb_defio); if (!ufx_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) { - retval = -ENOMEM; dev_err(dev->gdev, "ufx_alloc_urb_list failed\n"); - goto error; + goto e_nomem; } /* We don't register a new USB class. Our client interface is fbdev */ @@ -1662,9 +1661,8 @@ static int ufx_usb_probe(struct usb_interface *interface, /* allocates framebuffer driver structure, not framebuffer memory */ info = framebuffer_alloc(0, &usbdev->dev); if (!info) { - retval = -ENOMEM; dev_err(dev->gdev, "framebuffer_alloc failed\n"); - goto error; + goto e_nomem; } dev->info = info; @@ -1675,7 +1673,7 @@ static int ufx_usb_probe(struct usb_interface *interface, retval = fb_alloc_cmap(&info->cmap, 256, 0); if (retval < 0) { dev_err(dev->gdev, "fb_alloc_cmap failed %x\n", retval); - goto error; + goto destroy_modedb; } INIT_DELAYED_WORK(&dev->free_framebuffer_work, @@ -1736,26 +1734,20 @@ static int ufx_usb_probe(struct usb_interface *interface, return 0; error: - if (dev) { - if (info) { - if (info->cmap.len != 0) - fb_dealloc_cmap(&info->cmap); - if (info->monspecs.modedb) - fb_destroy_modedb(info->monspecs.modedb); - vfree(info->screen_base); - - fb_destroy_modelist(&info->modelist); - - framebuffer_release(info); - } - - kref_put(&dev->kref, ufx_free); /* ref for framebuffer */ - kref_put(&dev->kref, ufx_free); /* last ref from kref_init */ - - /* dev has been deallocated. Do not dereference */ - } - + fb_dealloc_cmap(&info->cmap); +destroy_modedb: + fb_destroy_modedb(info->monspecs.modedb); + vfree(info->screen_base); + fb_destroy_modelist(&info->modelist); + framebuffer_release(info); +put_ref: + kref_put(&dev->kref, ufx_free); /* ref for framebuffer */ + kref_put(&dev->kref, ufx_free); /* last ref from kref_init */ return retval; + +e_nomem: + retval = -ENOMEM; + goto put_ref; } static void ufx_usb_disconnect(struct usb_interface *interface) -- 2.15.1 -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html