From: Thomas Weißschuh <linux@weissschuh.net> mainline inclusion from mainline-v6.12-rc1 commit 929c81ade6355b87097a2a4886c10750e68626cf category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBY436 CVE: CVE-2025-21976 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Introduce a device-managed variant of register_framebuffer() which automatically unregisters the framebuffer on device destruction. This can simplify the error handling and resource management in drivers. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Helge Deller <deller@gmx.de> Conflicts: include/linux/fb.h [context conflicts] Signed-off-by: Xiangwei Li <liwei728@huawei.com> --- drivers/video/fbdev/core/fbmem.c | 30 ++++++++++++++++++++++++++++++ include/linux/fb.h | 1 + 2 files changed, 31 insertions(+) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index ee44a46a66be..990a4e63a916 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1084,6 +1084,36 @@ unregister_framebuffer(struct fb_info *fb_info) } EXPORT_SYMBOL(unregister_framebuffer); +static void devm_unregister_framebuffer(void *data) +{ + struct fb_info *info = data; + + unregister_framebuffer(info); +} + +/** + * devm_register_framebuffer - resource-managed frame buffer device registration + * @dev: device the framebuffer belongs to + * @fb_info: frame buffer info structure + * + * Registers a frame buffer device @fb_info to device @dev. + * + * Returns negative errno on error, or zero for success. + * + */ +int +devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) +{ + int ret; + + ret = register_framebuffer(fb_info); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); +} +EXPORT_SYMBOL(devm_register_framebuffer); + /** * fb_set_suspend - low level driver signals suspend * @info: framebuffer affected diff --git a/include/linux/fb.h b/include/linux/fb.h index 195513d589c2..2b917f2a2400 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -598,6 +598,7 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf, /* fbmem.c */ extern int register_framebuffer(struct fb_info *fb_info); extern void unregister_framebuffer(struct fb_info *fb_info); +extern int devm_register_framebuffer(struct device *dev, struct fb_info *fb_info); extern int fb_prepare_logo(struct fb_info *fb_info, int rotate); extern int fb_show_logo(struct fb_info *fb_info, int rotate); extern char* fb_get_buffer_offset(struct fb_info *info, struct fb_pixmap *buf, u32 size); -- 2.25.1