[PATCH v2 17/17] arm64: ssbd: Implement arch_seccomp_spec_mitigate

From: Marc Zyngier
Date: Tue May 29 2018 - 08:12:26 EST


Now that we have a way to safely implement TIF_SSBD for tasks
that are not in the kernel at the point were the flag gets
set, let's implement arch_seccomp_spec_mitigate().

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
arch/arm64/kernel/ssbd.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/arm64/kernel/ssbd.c b/arch/arm64/kernel/ssbd.c
index 34eafdc7fb6b..a61da5e1b2ed 100644
--- a/arch/arm64/kernel/ssbd.c
+++ b/arch/arm64/kernel/ssbd.c
@@ -77,6 +77,13 @@ int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which,
}
}

+#ifdef CONFIG_SECCOMP
+void arch_seccomp_spec_mitigate(struct task_struct *task)
+{
+ ssbd_prctl_set(task, PR_SPEC_FORCE_DISABLE);
+}
+#endif
+
static int ssbd_prctl_get(struct task_struct *task)
{
switch (arm64_get_ssbd_state()) {
--
2.14.2