From: Gleb Natapov <g...@redhat.com> fix segment_base() to properly check for null segment selector and avoid accessing NULL pointer if ldt selector in null.
Signed-off-by: Gleb Natapov <g...@redhat.com> Signed-off-by: Avi Kivity <a...@redhat.com> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 5e20805..d5e8437 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -229,7 +229,7 @@ unsigned long segment_base(u16 selector) unsigned long table_base; unsigned long v; - if (selector == 0) + if (!(selector & ~3)) return 0; native_store_gdt(&gdt); @@ -238,6 +238,8 @@ unsigned long segment_base(u16 selector) if (selector & 4) { /* from ldt */ u16 ldt_selector = kvm_read_ldt(); + if (!(ldt_selector & ~3)) + return 0; table_base = segment_base(ldt_selector); } d = (struct desc_struct *)(table_base + (selector & ~7)); -- To unsubscribe from this list: send the line "unsubscribe kvm-commits" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html