[03/43] p54: Initialize extra_len in p54_tx_80211

From: Greg KH
Date: Thu May 05 2011 - 20:36:26 EST


2.6.33-longterm review patch. If anyone has any objections, please let us know.

------------------

From: Jason Conti <jason.conti@xxxxxxxxx>

commit a6756da9eace8b4af73e9dea43f1fc2889224c94 upstream.

This patch fixes a very serious off-by-one bug in
the driver, which could leave the device in an
unresponsive state.

The problem was that the extra_len variable [used to
reserve extra scratch buffer space for the firmware]
was left uninitialized. Because p54_assign_address
later needs the value to reserve additional space,
the resulting frame could be to big for the small
device's memory window and everything would
immediately come to a grinding halt.

Reference: https://bugs.launchpad.net/bugs/722185

Acked-by: Christian Lamparter <chunkeey@xxxxxxxxxxxxxx>
Signed-off-by: Jason Conti <jason.conti@xxxxxxxxx>
Signed-off-by: John W. Linville <linville@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/net/wireless/p54/txrx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/wireless/p54/txrx.c
+++ b/drivers/net/wireless/p54/txrx.c
@@ -703,7 +703,7 @@ int p54_tx_80211(struct ieee80211_hw *de
struct p54_tx_info *p54info;
struct p54_hdr *hdr;
struct p54_tx_data *txhdr;
- unsigned int padding, len, extra_len;
+ unsigned int padding, len, extra_len = 0;
int i, j, ridx;
u16 hdr_flags = 0, aid = 0;
u8 rate, queue = 0, crypt_offset = 0;


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