[34-longterm 076/260] ath5k: check return value of ieee80211_get_tx_rate

Paul Gortmaker
2011-01-02T08:02:20Z

From: John W. Linville <linville@tuxdriver.com>

commit d8e1ba76d619dbc0be8fbeee4e6c683b5c812d3a upstream.

This avoids a NULL pointer dereference as reported here:

https://bugzilla.redhat.com/show_bug.cgi?id=625889

When the WARN condition is hit in ieee80211_get_tx_rate, it will return
NULL. So, we need to check the return value and avoid dereferencing it
in that case.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Acked-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
drivers/net/wireless/ath/ath5k/base.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index db84169..61023e9 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -1316,6 +1316,10 @@ ath5k_txbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf,
PCI_DMA_TODEVICE);

rate = ieee80211_get_tx_rate(sc->hw, info);
+ if (!rate) {
+ ret = -EINVAL;
+ goto err_unmap;
+ }

if (info->flags & IEEE80211_TX_CTL_NO_ACK)
flags |= AR5K_TXDESC_NOACK;
--
1.7.3.3