x86/sysfb: Fix check for bad VRAM size
authorArvind Sankar <nivedita@alum.mit.edu>
Tue, 7 Jan 2020 23:04:10 +0000 (18:04 -0500)
committerBorislav Petkov <bp@suse.de>
Mon, 20 Jan 2020 09:57:53 +0000 (10:57 +0100)
commitdacc9092336be20b01642afe1a51720b31f60369
treef9fe38a67c1e0629839cd47ec7be8b9d03da352d
parent163159aad74d3763b350861b879b41e8f64121fc
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
arch/x86/kernel/sysfb_simplefb.c