diff options
| author | Yongzhen Zhang <zhangyongzhen@kylinos.cn> | 2025-07-01 17:07:04 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-20 18:30:40 +0200 |
| commit | 806f85bdd3a60187c21437fc51baace11f659f35 (patch) | |
| tree | 9e3a7ee1bc8fa938748d7ee0acde56f693074c77 | |
| parent | ec12068f10c1b8834e87e2bb195311d71dd0321f (diff) | |
fbdev: fix potential buffer overflow in do_register_framebuffer()
[ Upstream commit 523b84dc7ccea9c4d79126d6ed1cf9033cf83b05 ]
The current implementation may lead to buffer overflow when:
1. Unregistration creates NULL gaps in registered_fb[]
2. All array slots become occupied despite num_registered_fb < FB_MAX
3. The registration loop exceeds array bounds
Add boundary check to prevent registered_fb[FB_MAX] access.
Signed-off-by: Yongzhen Zhang <zhangyongzhen@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/video/fbdev/core/fbmem.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index eca2498f2436..6a033bf17ab6 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -403,6 +403,9 @@ static int do_register_framebuffer(struct fb_info *fb_info) if (!registered_fb[i]) break; + if (i >= FB_MAX) + return -ENXIO; + if (!fb_info->modelist.prev || !fb_info->modelist.next) INIT_LIST_HEAD(&fb_info->modelist); |