diff options
| author | Arvind Sankar <nivedita@alum.mit.edu> | 2020-01-07 18:04:10 -0500 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-01-20 10:57:53 +0100 |
| commit | dacc9092336be20b01642afe1a51720b31f60369 (patch) | |
| tree | f9fe38a67c1e0629839cd47ec7be8b9d03da352d /arch/x86/kernel/sysfb_simplefb.c | |
| parent | 163159aad74d3763b350861b879b41e8f64121fc (diff) | |
| download | lwn-dacc9092336be20b01642afe1a51720b31f60369.tar.gz lwn-dacc9092336be20b01642afe1a51720b31f60369.zip | |
x86/sysfb: Fix check for bad VRAM size
When checking whether the reported lfb_size makes sense, the height
* stride result is page-aligned before seeing whether it exceeds the
reported size.
This doesn't work if height * stride is not an exact number of pages.
For example, as reported in the kernel bugzilla below, an 800x600x32 EFI
framebuffer gets skipped because of this.
Move the PAGE_ALIGN to after the check vs size.
Reported-by: Christopher Head <chead@chead.ca>
Tested-by: Christopher Head <chead@chead.ca>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206051
Link: https://lkml.kernel.org/r/20200107230410.2291947-1-nivedita@alum.mit.edu
Diffstat (limited to 'arch/x86/kernel/sysfb_simplefb.c')
| -rw-r--r-- | arch/x86/kernel/sysfb_simplefb.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/sysfb_simplefb.c b/arch/x86/kernel/sysfb_simplefb.c index 01f0e2263b86..298fc1edd9c9 100644 --- a/arch/x86/kernel/sysfb_simplefb.c +++ b/arch/x86/kernel/sysfb_simplefb.c @@ -90,11 +90,11 @@ __init int create_simplefb(const struct screen_info *si, if (si->orig_video_isVGA == VIDEO_TYPE_VLFB) size <<= 16; length = mode->height * mode->stride; - length = PAGE_ALIGN(length); if (length > size) { printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n"); return -EINVAL; } + length = PAGE_ALIGN(length); /* setup IORESOURCE_MEM as framebuffer memory */ memset(&res, 0, sizeof(res)); |