4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jean Delvare <jdelvare@xxxxxxx> [ Upstream commit 90fe6f8ff00a07641ca893d64f75ca22ce77cca2 ] The test which ensures that the DMI type 1 structure is long enough to hold the UUID is off by one. It would fail if the structure is exactly 24 bytes long, while that's sufficient to hold the UUID. I don't expect this bug to cause problem in practice because all implementations I have seen had length 8, 25 or 27 bytes, in line with the SMBIOS specifications. But let's fix it still. Signed-off-by: Jean Delvare <jdelvare@xxxxxxx> Fixes: a814c3597a6b ("firmware: dmi_scan: Check DMI structure length") Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/firmware/dmi_scan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -186,7 +186,7 @@ static void __init dmi_save_uuid(const s char *s; int is_ff = 1, is_00 = 1, i; - if (dmi_ident[slot] || dm->length <= index + 16) + if (dmi_ident[slot] || dm->length < index + 16) return; d = (u8 *) dm + index;