ath5k: warn and correct rate for unknown hw rate indexes

upstream commit: b726604706ad88d8b28bc487e45e710f58cc19ee

ath5k sets up a mapping table from the hardware rate index to
the rate index used by mac80211; however, we have seen some
received frames with incorrect rate indexes.  Such frames
normally get dropped with a warning in __ieee80211_rx(),
but it doesn't include enough information to track down the
error.

This patch adds a warning to hw_to_driver_rix for any lookups
that result in a rate index of -1, then returns a valid rate so
the frame can be processed.

Changes-licensed-under: 3-Clause-BSD

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[chrisw: add db5b4f7ae3901fdc48c5b988fc2a5e0cb4ec1870 to backport]
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
index a3392f3a95e77a9996e1d31f7f871bbe8980ef3b..6cf69d3e3c5fdcde4c35ee388737533b3772f012 100644 (file)
--- a/drivers/net/wireless/ath5k/base.c
+++ b/drivers/net/wireless/ath5k/base.c
@@ -1090,8 +1090,18 @@ ath5k_mode_setup(struct ath5k_softc *sc)
 static inline int
 ath5k_hw_to_driver_rix(struct ath5k_softc *sc, int hw_rix)
 {
-       WARN_ON(hw_rix < 0 || hw_rix > AR5K_MAX_RATES);
-       return sc->rate_idx[sc->curband->band][hw_rix];
+       int rix;
+
+       /* return base rate on errors */
+       if (WARN(hw_rix < 0 || hw_rix >= AR5K_MAX_RATES,
+                       "hw_rix out of bounds: %x\n", hw_rix))
+               return 0;
+
+       rix = sc->rate_idx[sc->curband->band][hw_rix];
+       if (WARN(rix < 0, "invalid hw_rix: %x\n", hw_rix))
+               rix = 0;
+
+       return rix;
 }
 
 /***************\

diff --git a/drivers/net/wireless/ath5k/base.h b/drivers/net/wireless/ath5k/base.h
index facc60ddada2824ceba476c8efcda1a66a398a1d..d86ab393b0a59b91917b696c31f841c685ea3911 100644 (file)
--- a/drivers/net/wireless/ath5k/base.h
+++ b/drivers/net/wireless/ath5k/base.h
@@ -112,7 +112,7 @@ struct ath5k_softc {
        struct ieee80211_supported_band sbands[IEEE80211_NUM_BANDS];
        struct ieee80211_channel channels[ATH_CHAN_MAX];
        struct ieee80211_rate   rates[IEEE80211_NUM_BANDS][AR5K_MAX_RATES];
-       u8                      rate_idx[IEEE80211_NUM_BANDS][AR5K_MAX_RATES];
+       s8                      rate_idx[IEEE80211_NUM_BANDS][AR5K_MAX_RATES];
        enum nl80211_iftype     opmode;
        struct ath5k_hw         *ah;            /* Atheros HW */