diff options
| author | Helge Deller <deller@gmx.de> | 2022-06-29 15:53:55 +0200 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2022-07-07 10:52:21 +0200 |
| commit | 6c11df58fd1ac0aefcb3b227f72769272b939e56 (patch) | |
| tree | cfffe612addc6988e362bdb639c56e384a092718 | |
| parent | e64242caef18b4a5840b0e7a9bff37abd4f4f933 (diff) | |
| download | lwn-6c11df58fd1ac0aefcb3b227f72769272b939e56.tar.gz lwn-6c11df58fd1ac0aefcb3b227f72769272b939e56.zip | |
fbmem: Check virtual screen sizes in fb_set_var()
Verify that the fbdev or drm driver correctly adjusted the virtual
screen sizes. On failure report the failing driver and reject the screen
size change.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # v5.4+
| -rw-r--r-- | drivers/video/fbdev/core/fbmem.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 7dc6848a96bb..7ee6eb2fa715 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1017,6 +1017,16 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var) if (ret) return ret; + /* verify that virtual resolution >= physical resolution */ + if (var->xres_virtual < var->xres || + var->yres_virtual < var->yres) { + pr_warn("WARNING: fbcon: Driver '%s' missed to adjust virtual screen size (%ux%u vs. %ux%u)\n", + info->fix.id, + var->xres_virtual, var->yres_virtual, + var->xres, var->yres); + return -EINVAL; + } + if ((var->activate & FB_ACTIVATE_MASK) != FB_ACTIVATE_NOW) return 0; |