diff mbox series

[v29,06/10] x86/cet/ibt: Update arch_prctl functions for Indirect Branch Tracking

Message ID 20210820182245.1188-7-yu-cheng.yu@intel.com (mailing list archive)
State New
Headers show
Series Control-flow Enforcement: Indirect Branch Tracking | expand

Commit Message

Yu-cheng Yu Aug. 20, 2021, 6:22 p.m. UTC 
From: "H.J. Lu" <hjl.tools@gmail.com>

Update ARCH_X86_CET_STATUS and ARCH_X86_CET_DISABLE for Indirect Branch
Tracking.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
 arch/x86/kernel/cet_prctl.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/arch/x86/kernel/cet_prctl.c b/arch/x86/kernel/cet_prctl.c
index b426d200e070..bd3c80d402e7 100644
--- a/arch/x86/kernel/cet_prctl.c
+++ b/arch/x86/kernel/cet_prctl.c
@@ -22,6 +22,9 @@  static int cet_copy_status_to_user(struct thread_shstk *shstk, u64 __user *ubuf)
 		buf[2] = shstk->size;
 	}
 
+	if (shstk->ibt)
+		buf[0] |= GNU_PROPERTY_X86_FEATURE_1_IBT;
+
 	return copy_to_user(ubuf, buf, sizeof(buf));
 }
 
@@ -46,6 +49,8 @@  int prctl_cet(int option, u64 arg2)
 			return -EINVAL;
 		if (arg2 & GNU_PROPERTY_X86_FEATURE_1_SHSTK)
 			shstk_disable();
+		if (arg2 & GNU_PROPERTY_X86_FEATURE_1_IBT)
+			ibt_disable();
 		return 0;
 
 	case ARCH_X86_CET_LOCK: