Message ID | 21023.1508770184@warthog.procyon.org.uk (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hi David, On Mon, Oct 23, 2017 at 03:49:44PM +0100, David Howells wrote: > Alan Cox <gnomes@lxorguk.ukuu.org.uk> wrote: > > > There are a load of standard tools that use this so I think you are going > > to need a whitelist. Can you at least log *which* MSR in the failing case > > so a whitelist can be built over time ? > > Will the attached change work for you? > It's good to me. Joey Lee > --- > diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c > index a05a97863286..f18cadbc31ce 100644 > --- a/arch/x86/kernel/msr.c > +++ b/arch/x86/kernel/msr.c > @@ -84,8 +84,10 @@ static ssize_t msr_write(struct file *file, const char __user *buf, > int err = 0; > ssize_t bytes = 0; > > - if (kernel_is_locked_down("Direct MSR access")) > + if (kernel_is_locked_down("Direct MSR access")) { > + pr_info("Direct access to MSR %x\n", reg); > return -EPERM; > + } > > if (count % 8) > return -EINVAL; /* Invalid chunk size */ > @@ -135,6 +137,7 @@ static long msr_ioctl(struct file *file, unsigned int ioc, unsigned long arg) > break; > } > if (kernel_is_locked_down("Direct MSR access")) { > + pr_info("Direct access to MSR %x\n", reg[1]); /* Display %ecx */ > err = -EPERM; > break; > } -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c index a05a97863286..f18cadbc31ce 100644 --- a/arch/x86/kernel/msr.c +++ b/arch/x86/kernel/msr.c @@ -84,8 +84,10 @@ static ssize_t msr_write(struct file *file, const char __user *buf, int err = 0; ssize_t bytes = 0; - if (kernel_is_locked_down("Direct MSR access")) + if (kernel_is_locked_down("Direct MSR access")) { + pr_info("Direct access to MSR %x\n", reg); return -EPERM; + } if (count % 8) return -EINVAL; /* Invalid chunk size */ @@ -135,6 +137,7 @@ static long msr_ioctl(struct file *file, unsigned int ioc, unsigned long arg) break; } if (kernel_is_locked_down("Direct MSR access")) { + pr_info("Direct access to MSR %x\n", reg[1]); /* Display %ecx */ err = -EPERM; break; }