Commit 940ede60 authored Jan 03, 2023 by Rodrigo Branco Committed by Greg Kroah-Hartman Jan 18, 2023

x86/bugs: Flush IBP in ib_prctl_set()



commit a664ec9158eeddd75121d39c9a0758016097fa96 upstream.

We missed the window between the TIF flag update and the next reschedule.

Signed-off-by: Rodrigo Branco <bsdaemon@google.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent c2d46555

arch/x86/kernel/cpu/bugs.c

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -1778,6 +1778,8 @@ static int ib_prctl_set(struct task_struct *task, unsigned long ctrl)
	if (ctrl == PR_SPEC_FORCE_DISABLE)		if (ctrl == PR_SPEC_FORCE_DISABLE)
	task_set_spec_ib_force_disable(task);		task_set_spec_ib_force_disable(task);
	task_update_spec_tif(task);		task_update_spec_tif(task);
			if (task == current)
			indirect_branch_prediction_barrier();
	break;		break;
	default:		default:
	return -ERANGE;		return -ERANGE;