diff mbox series

hardening: Enable KFENCE in the hardening config

Message ID 20240212130116.997627-1-elver@google.com
State New
Headers
Series hardening: Enable KFENCE in the hardening config |

Commit Message

Marco Elver Feb. 12, 2024, 1:01 p.m. UTC 
  KFENCE is not a security mitigation mechanism (due to sampling), but has
the performance characteristics of unintrusive hardening techniques.
When used at scale, however, it improves overall security by allowing
kernel developers to detect heap memory-safety bugs cheaply.

Link: https://lkml.kernel.org/r/79B9A832-B3DE-4229-9D87-748B2CFB7D12@kernel.org
Cc: Matthieu Baerts <matttbe@kernel.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Marco Elver <elver@google.com>
---
 kernel/configs/hardening.config | 3 +++
 1 file changed, 3 insertions(+)

Comments

Matthieu Baerts (NGI0) Feb. 12, 2024, 2:07 p.m. UTC | #1 
Hi Marco,

On 12/02/2024 14:01, Marco Elver wrote:
> KFENCE is not a security mitigation mechanism (due to sampling), but has
> the performance characteristics of unintrusive hardening techniques.
> When used at scale, however, it improves overall security by allowing
> kernel developers to detect heap memory-safety bugs cheaply.

Thank you for having sent this patch!

Cheers,
Matt
Kees Cook Feb. 12, 2024, 7:04 p.m. UTC | #2 
On Mon, Feb 12, 2024 at 02:01:09PM +0100, Marco Elver wrote:
> KFENCE is not a security mitigation mechanism (due to sampling), but has
> the performance characteristics of unintrusive hardening techniques.
> When used at scale, however, it improves overall security by allowing
> kernel developers to detect heap memory-safety bugs cheaply.
> 
> Link: https://lkml.kernel.org/r/79B9A832-B3DE-4229-9D87-748B2CFB7D12@kernel.org
> Cc: Matthieu Baerts <matttbe@kernel.org>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Signed-off-by: Marco Elver <elver@google.com>

Thanks! Applied to my for-next/hardening tree.

https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git/commit/?h=for-next/hardening&id=1f82cb2f3859540120e990a79abfee8151ea6b93

-Kees
diff mbox series

Patch

diff --git a/kernel/configs/hardening.config b/kernel/configs/hardening.config
index 95a400f042b1..79c865bfb116 100644
--- a/kernel/configs/hardening.config
+++ b/kernel/configs/hardening.config
@@ -46,6 +46,9 @@  CONFIG_UBSAN_BOUNDS=y
 # CONFIG_UBSAN_ALIGNMENT
 CONFIG_UBSAN_SANITIZE_ALL=y
 
+# Sampling-based heap out-of-bounds and use-after-free detection.
+CONFIG_KFENCE=y
+
 # Linked list integrity checking.
 CONFIG_LIST_HARDENED=y