Re: [PATCH] mac80211: Do not use sizeof() on pointer type

From: Arend van Spriel
Date: Wed Aug 26 2015 - 16:23:31 EST

On 08/26/2015 12:22 PM, Thierry Reding wrote:
From: Thierry Reding <treding@xxxxxxxxxx>

The rate_control_cap_mask() function takes a parameter mcs_mask, which
GCC will take to be u8 * even though it was declared with a fixed size.
This causes the following warning:

net/mac80211/rate.c: In function 'rate_control_cap_mask':
net/mac80211/rate.c:719:25: warning: 'sizeof' on array function parameter 'mcs_mask' will return size of 'u8 * {aka unsigned char *}' [-Wsizeof-array-argument]
for (i = 0; i < sizeof(mcs_mask); i++)
net/mac80211/rate.c:684:10: note: declared here
u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],

This can be easily fixed by using the IEEE80211_HT_MCS_MASK_LEN directly
within the loop condition.

Or use ARRAY_SIZE(mcs_mask).


Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
net/mac80211/rate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
index 9857693b91ec..9ce8883d5f44 100644
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -716,7 +716,7 @@ static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata,

/* Filter out rates that the STA does not support */
*mask &= sta->supp_rates[sband->band];
- for (i = 0; i < sizeof(mcs_mask); i++)
+ for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++)
mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i];

sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map;

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