fbdev: efifb: Register sysfs groups through driver core

The driver core can register and cleanup sysfs groups already.
Make use of that functionality to simplify the error handling and
cleanup.

Also avoid a UAF race during unregistering where the sysctl attributes
were usable after the info struct was freed.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Helge Deller <deller@gmx.de>
This commit is contained in:
Thomas Weißschuh 2024-08-27 17:25:13 +02:00 committed by Helge Deller
parent 929c81ade6
commit 95cdd538e0

View File

@ -561,15 +561,10 @@ static int efifb_probe(struct platform_device *dev)
break;
}
err = sysfs_create_groups(&dev->dev.kobj, efifb_groups);
if (err) {
pr_err("efifb: cannot add sysfs attrs\n");
goto err_unmap;
}
err = fb_alloc_cmap(&info->cmap, 256, 0);
if (err < 0) {
pr_err("efifb: cannot allocate colormap\n");
goto err_groups;
goto err_unmap;
}
err = devm_aperture_acquire_for_platform_device(dev, par->base, par->size);
@ -587,8 +582,6 @@ static int efifb_probe(struct platform_device *dev)
err_fb_dealloc_cmap:
fb_dealloc_cmap(&info->cmap);
err_groups:
sysfs_remove_groups(&dev->dev.kobj, efifb_groups);
err_unmap:
if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC))
iounmap(info->screen_base);
@ -608,12 +601,12 @@ static void efifb_remove(struct platform_device *pdev)
/* efifb_destroy takes care of info cleanup */
unregister_framebuffer(info);
sysfs_remove_groups(&pdev->dev.kobj, efifb_groups);
}
static struct platform_driver efifb_driver = {
.driver = {
.name = "efi-framebuffer",
.dev_groups = efifb_groups,
},
.probe = efifb_probe,
.remove_new = efifb_remove,