On 1/19/2021 4:04 AM, Borislav Petkov wrote:
On Tue, Dec 29, 2020 at 01:30:33PM -0800, Yu-cheng Yu wrote:
[...]
+DEFINE_IDTENTRY_ERRORCODE(exc_control_protection) +{ + struct task_struct *tsk; + + if (!user_mode(regs)) { + if (notify_die(DIE_TRAP, "control protection fault", regs, + error_code, X86_TRAP_CP, SIGSEGV) == NOTIFY_STOP) + return; + die("Upexpected/unsupported kernel control protection fault", regs, error_code);Isn't the machine supposed to panic() here and do no further progress?
Ok, make it panic().
+ } + + cond_local_irq_enable(regs); + + if (!boot_cpu_has(X86_FEATURE_CET)) + WARN_ONCE(1, "Control protection fault with CET support disabled\n"); + + tsk = current; + tsk->thread.error_code = error_code; + tsk->thread.trap_nr = X86_TRAP_CP; + + if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) && + printk_ratelimit()) {WARNING: Prefer printk_ratelimited or pr_<level>_ratelimited to printk_ratelimit #136: FILE: arch/x86/kernel/traps.c:645: + printk_ratelimit()) { Still not using checkpatch?
Most places in arch/x86 still use printk_ratelimit(). I should have trusted checkpatch. I will fix it.
+ unsigned int max_err; + unsigned long ssp; + + max_err = ARRAY_SIZE(control_protection_err) - 1; + if ((error_code < 0) || (error_code > max_err)) + error_code = 0; + + rdmsrl(MSR_IA32_PL3_SSP, ssp); + pr_info("%s[%d] control protection ip:%lx sp:%lx ssp:%lx error:%lx(%s)",If anything, all this stuff should be pr_emerg().
I will fix it. -- Yu-cheng
