[bpf-next] bpf: Avoid unnecessary audit log for CPU security mitigations

Commit Message

Yafang Shao Oct. 13, 2023, 8:39 a.m. UTC

Check cpu_mitigations_off() first to avoid calling capable() if it is off. 
This can avoid unnecessary audit log.

Fixes: bc5bc309db45 ("bpf: Inherit system settings for CPU security mitigations")
Link: https://lore.kernel.org/bpf/CAEf4Bza6UVUWqcWQ-66weZ-nMDr+TFU3Mtq=[e-mail]/
Suggested-by: Andrii Nakryiko <[e-mail]>
Signed-off-by: Yafang Shao <[e-mail]>
---
 include/linux/bpf.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

[e-mail] Oct. 13, 2023, 7:40 p.m. UTC | #1

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Andrii Nakryiko <[e-mail]>:

On Fri, 13 Oct 2023 08:39:16 +0000 you wrote:
> Check cpu_mitigations_off() first to avoid calling capable() if it is off.
> This can avoid unnecessary audit log.
> 
> Fixes: bc5bc309db45 ("bpf: Inherit system settings for CPU security mitigations")
> Link: https://lore.kernel.org/bpf/CAEf4Bza6UVUWqcWQ-66weZ-nMDr+TFU3Mtq=[e-mail]/
> Suggested-by: Andrii Nakryiko <[e-mail]>
> Signed-off-by: Yafang Shao <[e-mail]>
> 
> [...]

Here is the summary with links:
  - [bpf-next] bpf: Avoid unnecessary audit log for CPU security mitigations
    https://git.kernel.org/bpf/bpf-next/c/236334aeec0f

You are awesome, thank you!

Patch

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 61bde45..f0891ba 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2164,12 +2164,12 @@  static inline bool bpf_allow_uninit_stack(void)
 
 static inline bool bpf_bypass_spec_v1(void)
 {
-	return perfmon_capable() || cpu_mitigations_off();
+	return cpu_mitigations_off() || perfmon_capable();
 }
 
 static inline bool bpf_bypass_spec_v4(void)
 {
-	return perfmon_capable() || cpu_mitigations_off();
+	return cpu_mitigations_off() || perfmon_capable();
 }
 
 int bpf_map_new_fd(struct bpf_map *map, int flags);