[PATCH v3] ath9k: dfs: Remove VLA usage

From: Kees Cook
Date: Tue Apr 24 2018 - 19:58:11 EST


In the quest to remove all stack VLA usage from the kernel[1], this
redefines FFT_NUM_SAMPLES as a #define instead of const int, which still
triggers gcc's VLA checking pass.

[1] https://lkml.org/lkml/2018/3/7/621

Co-developed-by: Andreas Christoforou <andreaschristofo@xxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
v3: replace FFT_NUM_SAMPLES as a #define (Joe)
---
drivers/net/wireless/ath/ath9k/dfs.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/dfs.c b/drivers/net/wireless/ath/ath9k/dfs.c
index 6fee9a464cce..e6e56a925121 100644
--- a/drivers/net/wireless/ath/ath9k/dfs.c
+++ b/drivers/net/wireless/ath/ath9k/dfs.c
@@ -40,8 +40,8 @@ static const int BIN_DELTA_MIN = 1;
static const int BIN_DELTA_MAX = 10;

/* we need at least 3 deltas / 4 samples for a reliable chirp detection */
-#define NUM_DIFFS 3
-static const int FFT_NUM_SAMPLES = (NUM_DIFFS + 1);
+#define NUM_DIFFS 3
+#define FFT_NUM_SAMPLES (NUM_DIFFS + 1)

/* Threshold for difference of delta peaks */
static const int MAX_DIFF = 2;
--
2.7.4


--
Kees Cook
Pixel Security