Size of array passed to print_array_to_buf_index is decremented by 1

Discovered in coverity scan, CID 1600742
---
Changes in v2:
- Code style: added spaces before and after '-'
- Link to v1: https://lore.kernel.org/all/8734kpq0wo.fsf@kernel.org/
---

Signed-off-by: Karol Przybylski <karprzy7@gmail.com>
---
 drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c b/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
index 799b865b89e5..8371df570c42 100644
--- a/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
+++ b/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
@@ -1590,7 +1590,7 @@ ath12k_htt_print_tx_selfgen_ax_stats_tlv(const void *tag_buf, u16 tag_len,
 			 le32_to_cpu(htt_stats_buf->ax_mu_mimo_ndp));
 	len += print_array_to_buf_index(buf, len, "ax_mu_mimo_brpollX_tried = ", 1,
 					htt_stats_buf->ax_mu_mimo_brpoll,
-					ATH12K_HTT_TX_NUM_AX_MUMIMO_USER_STATS, "\n");
+					ATH12K_HTT_TX_NUM_AX_MUMIMO_USER_STATS - 1, "\n");
 	len += scnprintf(buf + len, buf_len - len, "ax_basic_trigger = %u\n",
 			 le32_to_cpu(htt_stats_buf->ax_basic_trigger));
 	len += scnprintf(buf + len, buf_len - len, "ax_ulmumimo_total_trigger = %u\n",
-- 
2.34.1

On 10/21/2024 1:48 PM, Karol Przybylski wrote:
> Size of array passed to print_array_to_buf_index is decremented by 1

This is not a clear commit message.
Please follow the order normally used in the kernel:
1) describe the current code
2) describe the problem with the current code
3) describe how to fix the code (in imperative voice)

> 
> Discovered in coverity scan, CID 1600742
> ---
> Changes in v2:
> - Code style: added spaces before and after '-'
> - Link to v1: https://lore.kernel.org/all/8734kpq0wo.fsf@kernel.org/
> ---
> 
> Signed-off-by: Karol Przybylski <karprzy7@gmail.com>

SOB needs to be before the first "---"

> ---
>  drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c b/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
> index 799b865b89e5..8371df570c42 100644
> --- a/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
> +++ b/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
> @@ -1590,7 +1590,7 @@ ath12k_htt_print_tx_selfgen_ax_stats_tlv(const void *tag_buf, u16 tag_len,
>  			 le32_to_cpu(htt_stats_buf->ax_mu_mimo_ndp));
>  	len += print_array_to_buf_index(buf, len, "ax_mu_mimo_brpollX_tried = ", 1,
>  					htt_stats_buf->ax_mu_mimo_brpoll,
> -					ATH12K_HTT_TX_NUM_AX_MUMIMO_USER_STATS, "\n");
> +					ATH12K_HTT_TX_NUM_AX_MUMIMO_USER_STATS - 1, "\n");
>  	len += scnprintf(buf + len, buf_len - len, "ax_basic_trigger = %u\n",
>  			 le32_to_cpu(htt_stats_buf->ax_basic_trigger));
>  	len += scnprintf(buf + len, buf_len - len, "ax_ulmumimo_total_trigger = %u\n",

Aren't there more than this one? This also looks suspect:

	len += print_array_to_buf_index(buf, len, "ac_mu_mimo_brpollX_tried = ", 1,
					htt_stats_buf->ac_mu_mimo_brpoll,
					ATH12K_HTT_TX_NUM_AC_MUMIMO_USER_STATS, "\n\n");