mirror of
https://github.com/torvalds/linux
synced 2024-10-06 19:34:19 +00:00
Revert "fbdev: Make fb_release() return -ENODEV if fbdev was unregistered"
This reverts commitaafa025c76
. That commit attempted to fix a NULL pointer dereference, caused by the struct fb_info associated with a framebuffer device to not longer be valid when the file descriptor was closed. The issue was exposed by commit27599aacba
("fbdev: Hot-unplug firmware fb devices on forced removal"), which added a new path that goes through the struct device removal instead of directly unregistering the fb. Most fbdev drivers have issues with the fb_info lifetime, because call to framebuffer_release() from their driver's .remove callback, rather than doing from fbops.fb_destroy callback. This meant that due to this switch, the fb_info was now destroyed too early, while references still existed, while before it was simply leaked. The patch we're reverting here reinstated that leak, hence "fixed" the regression. But the proper solution is to fix the drivers to not release the fb_info too soon. Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20220504115917.758787-1-javierm@redhat.com
This commit is contained in:
parent
841e512ffb
commit
135332f34b
|
@ -1434,10 +1434,7 @@ fb_release(struct inode *inode, struct file *file)
|
|||
__acquires(&info->lock)
|
||||
__releases(&info->lock)
|
||||
{
|
||||
struct fb_info * const info = file_fb_info(file);
|
||||
|
||||
if (!info)
|
||||
return -ENODEV;
|
||||
struct fb_info * const info = file->private_data;
|
||||
|
||||
lock_fb_info(info);
|
||||
if (info->fbops->fb_release)
|
||||
|
|
Loading…
Reference in a new issue