2013-04-15 16:32:36

by Karl Beldan

Subject: [PATCH] mac80211: fix rate control tx handler for VHT rates

From: Karl Beldan <[email protected]>

Handle VHT rates like HT ones, otherwise we easily trigger the pre-HT
rates WARN_ON(rc_rate->idx >= sband->n_bitrates) which will set
rc_rate->idx to -1.

Signed-off-by: Karl Beldan <[email protected]>
---
I dared some reformatting to fit the WARN_ON for the VHT idx.

net/mac80211/tx.c | 30 ++++++++++++++++--------------
1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index c93483f..cf522a2 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -742,16 +742,17 @@ ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
}

for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
+ struct ieee80211_tx_rate *rc_rate = &info->control.rates[i];
/*
* make sure there's no valid rate following
* an invalid one, just in case drivers don't
* take the API seriously to stop at -1.
*/
if (inval) {
- info->control.rates[i].idx = -1;
+ rc_rate->idx = -1;
continue;
}
- if (info->control.rates[i].idx < 0) {
+ if (rc_rate->idx < 0) {
inval = true;
continue;
}
@@ -760,36 +761,37 @@ ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
* For now assume MCS is already set up correctly, this
* needs to be fixed.
*/
- if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
- WARN_ON(info->control.rates[i].idx > 76);
+ if (rc_rate->flags & IEEE80211_TX_RC_MCS) {
+ WARN_ON(rc_rate->idx > 76);
+ continue;
+ }
+
+ if (rc_rate->flags & IEEE80211_TX_RC_VHT_MCS) {
+ WARN_ON(ieee80211_rate_get_vht_mcs(rc_rate) > 9);
continue;
}

/* set up RTS protection if desired */
if (rts)
- info->control.rates[i].flags |=
- IEEE80211_TX_RC_USE_RTS_CTS;
+ rc_rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS;

/* RC is busted */
- if (WARN_ON_ONCE(info->control.rates[i].idx >=
- sband->n_bitrates)) {
- info->control.rates[i].idx = -1;
+ if (WARN_ON_ONCE(rc_rate->idx >= sband->n_bitrates)) {
+ rc_rate->idx = -1;
continue;
}

- rate = &sband->bitrates[info->control.rates[i].idx];
+ rate = &sband->bitrates[rc_rate->idx];

/* set up short preamble */
if (short_preamble &&
rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
- info->control.rates[i].flags |=
- IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
+ rc_rate->flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;

/* set up G protection */
if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
rate->flags & IEEE80211_RATE_ERP_G)
- info->control.rates[i].flags |=
- IEEE80211_TX_RC_USE_CTS_PROTECT;
+ rc_rate->flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
}

return TX_CONTINUE;
--
1.8.2

2013-04-16 14:00:02

by Johannes Berg

Subject: Re: [PATCH] mac80211: fix rate control tx handler for VHT rates

On Mon, 2013-04-15 at 18:28 +0200, Karl Beldan wrote:
> From: Karl Beldan <[email protected]>
>
> Handle VHT rates like HT ones, otherwise we easily trigger the pre-HT
> rates WARN_ON(rc_rate->idx >= sband->n_bitrates) which will set
> rc_rate->idx to -1.

Applied, thanks.

johannes