2012-06-14 21:27:56

by Felix Fietkau

Subject: [PATCH 3.5] ath9k: fix invalid pointer access in the tx path

After setup_frame_info has been called, only info->control.rates is still
valid, other control fields have been overwritten by the ath_frame_info
data. Move the access to info->control.vif for checking short preamble
to setup_frame_info before it gets overwritten.

This regression was introduced in commit d47a61aa
"ath9k: Fix multi-VIF BSS handling"

Signed-off-by: Felix Fietkau <[email protected]>
Reported-by: Thomas Hühn <[email protected]>
Cc: Sujith Manoharan <[email protected]>
Cc: [email protected] [3.4]
---
drivers/net/wireless/ath/ath9k/ath9k.h | 1 +
drivers/net/wireless/ath/ath9k/xmit.c | 10 ++++++++--
2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index a277cf6..b5136a1 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -214,6 +214,7 @@ struct ath_frame_info {
enum ath9k_key_type keytype;
u8 keyix;
u8 retries;
+ bool short_preamble;
};

struct ath_buf_state {
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index d59dd01..59fbe5b 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -938,6 +938,7 @@ static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf,
struct ieee80211_tx_rate *rates;
const struct ieee80211_rate *rate;
struct ieee80211_hdr *hdr;
+ struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
int i;
u8 rix = 0;

@@ -957,8 +958,7 @@ static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf,
rate = ieee80211_get_rts_cts_rate(sc->hw, tx_info);
info->rtscts_rate = rate->hw_value;

- if (tx_info->control.vif &&
- tx_info->control.vif->bss_conf.use_short_preamble)
+ if (fi->short_preamble)
info->rtscts_rate |= rate->hw_value_short;

for (i = 0; i < 4; i++) {
@@ -1779,6 +1779,11 @@ static void setup_frame_info(struct ieee80211_hw *hw, struct sk_buff *skb,
struct ath_frame_info *fi = get_frame_info(skb);
struct ath_node *an = NULL;
enum ath9k_key_type keytype;
+ bool short_preamble = false;
+
+ if (tx_info->control.vif &&
+ tx_info->control.vif->bss_conf.use_short_preamble)
+ short_preamble = true;

keytype = ath9k_cmn_get_hw_crypto_keytype(skb);

@@ -1794,6 +1799,7 @@ static void setup_frame_info(struct ieee80211_hw *hw, struct sk_buff *skb,
fi->keyix = ATH9K_TXKEYIX_INVALID;
fi->keytype = keytype;
fi->framelen = framelen;
+ fi->short_preamble = short_preamble;
}

u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
--
1.7.3.2

2012-06-14 22:04:55

by Sujith Manoharan

Subject: [PATCH 3.5] ath9k: fix invalid pointer access in the tx path

Felix Fietkau wrote:
> After setup_frame_info has been called, only info->control.rates is still
> valid, other control fields have been overwritten by the ath_frame_info
> data. Move the access to info->control.vif for checking short preamble
> to setup_frame_info before it gets overwritten.
>
> This regression was introduced in commit d47a61aa
> "ath9k: Fix multi-VIF BSS handling"
>
> Signed-off-by: Felix Fietkau <[email protected]>
> Reported-by: Thomas H?hn <[email protected]>
> Cc: Sujith Manoharan <[email protected]>
> Cc: [email protected] [3.4]

Acked-by: Sujith Manoharan <[email protected]>

Sujith