This is a note to let you know that I've just added the patch titled
x86/bugs: Flush IBP in ib_prctl_set()
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-bugs-flush-ibp-in-ib_prctl_set.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a664ec9158eeddd75121d39c9a0758016097fa96 Mon Sep 17 00:00:00 2001
From: Rodrigo Branco <bsdaemon@xxxxxxxxxx>
Date: Tue, 3 Jan 2023 14:17:51 -0600
Subject: x86/bugs: Flush IBP in ib_prctl_set()
From: Rodrigo Branco <bsdaemon@xxxxxxxxxx>
commit a664ec9158eeddd75121d39c9a0758016097fa96 upstream.
We missed the window between the TIF flag update and the next reschedule.
Signed-off-by: Rodrigo Branco <bsdaemon@xxxxxxxxxx>
Reviewed-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/bugs.c | 2 ++
1 file changed, 2 insertions(+)
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1951,6 +1951,8 @@ static int ib_prctl_set(struct task_stru
if (ctrl == PR_SPEC_FORCE_DISABLE)
task_set_spec_ib_force_disable(task);
task_update_spec_tif(task);
+ if (task == current)
+ indirect_branch_prediction_barrier();
break;
default:
return -ERANGE;
Patches currently in stable-queue which might be from bsdaemon@xxxxxxxxxx are
queue-6.0/x86-bugs-flush-ibp-in-ib_prctl_set.patch
