diff options
Diffstat (limited to 'drivers/lguest/x86/core.c')
| -rw-r--r-- | drivers/lguest/x86/core.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c index a125109446dc..39f64c95de18 100644 --- a/drivers/lguest/x86/core.c +++ b/drivers/lguest/x86/core.c @@ -216,9 +216,10 @@ static int emulate_insn(struct lguest *lg) * guest_pa just subtracts the Guest's page_offset. */ unsigned long physaddr = guest_pa(lg, lg->regs->eip); - /* The guest_pa() function only works for Guest kernel addresses, but - * that's all we're trying to do anyway. */ - if (lg->regs->eip < lg->page_offset) + /* This must be the Guest kernel trying to do something, not userspace! + * The bottom two bits of the CS segment register are the privilege + * level. */ + if ((lg->regs->cs & 3) != GUEST_PL) return 0; /* Decoding x86 instructions is icky. */ |