x86, espfix: Make it possible to disable 16-bit support

[pandora-kernel.git] / arch / x86 / kernel / ldt.c

diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index ea69726..0a8e65e 100644 (file)
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -230,6 +230,11 @@ static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode)
                }
        }
 
+       if (!IS_ENABLED(CONFIG_X86_16BIT) && !ldt_info.seg_32bit) {
+               error = -EINVAL;
+               goto out_unlock;
+       }
+
        fill_ldt(&ldt, &ldt_info);
        if (oldmode)
                ldt.avl = 0;