On Mon, Jul 24, 2023 at 10:52 PM Simon Glass sjg@chromium.org wrote:
This is copying beyond the end of the destination buffer. Correct the code by using a constant for the buffer size.
This long-standing bug prevents virtio bootdevs working correctly on qemu-x86 at present.
Nice catch!
Signed-off-by: Simon Glass sjg@chromium.org Fixes: 0ca2426beae ("x86: Add support for running option ROMs natively")
arch/x86/lib/bios.c | 2 +- include/vesa.h | 4 +++- 2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/x86/lib/bios.c b/arch/x86/lib/bios.c index e29cae78e509..3a9d7f5ddd41 100644 --- a/arch/x86/lib/bios.c +++ b/arch/x86/lib/bios.c @@ -204,7 +204,7 @@ static u8 vbe_get_mode_info(struct vesa_state *mi)
realmode_interrupt(0x10, VESA_GET_MODE_INFO, 0x0000, mi->video_mode, 0x0000, buffer_seg, buffer_adr);
memcpy(mi->mode_info_block, buffer, sizeof(struct vesa_state));
memcpy(mi->mode_info_block, buffer, VESA_MODE_INFO_SIZE);
or "sizeof(struct vesa_mode_info)"
mi->valid = true; return 0;diff --git a/include/vesa.h b/include/vesa.h index 9285bfa921a2..28828ab56aa4 100644 --- a/include/vesa.h +++ b/include/vesa.h @@ -83,12 +83,14 @@ struct __packed vesa_mode_info { u8 reserved[206]; };
+#define VESA_MODE_INFO_SIZE 256
struct vesa_state { u16 video_mode; bool valid; union { struct vesa_mode_info vesa;
u8 mode_info_block[256];
u8 mode_info_block[VESA_MODE_INFO_SIZE]; };};
Reviewed-by: Bin Meng bmeng.cn@gmail.com