not enough rates in struct iwi_rateset

Jeremie Le Hen jeremie at
Sat Oct 21 22:51:05 UTC 2006


I have compiled my kernel with ProPolice and if_iwi happened to
trigger the stack smashing protector, which means there has been
a buffer overflow in a buffer allocated in the stack.

The buffer overflow occurs in iwi_auth_and_assoc(), and the only
buffer in this function is in struct iwi_rateset, which can
handle 12 rates, however according to kgdb ni->ni_rates.rs_nrates
has a value of 13.

I am not confident with the net80211 code, but a quick glance at
sys/net80211/_ieee80211.h shows that there may be up to 15 rates.
Therefore I bumped up the number of rates in iwi_rateset to 15
and there is no buffer overflow anymore, though I don't know if
this is the correct fix.

Best regards,
Jeremie Le Hen
< jeremie at le-hen dot org >< ttz at chchile dot org >
-------------- next part --------------
Index: if_iwireg.h
RCS file: /home/ncvs/src/sys/dev/iwi/if_iwireg.h,v
retrieving revision 1.12
diff -u -p -r1.12 if_iwireg.h
--- if_iwireg.h	27 Apr 2006 21:43:37 -0000	1.12
+++ if_iwireg.h	21 Oct 2006 22:38:34 -0000
@@ -338,7 +338,7 @@ struct iwi_rateset {
 	uint8_t	reserved;
-	uint8_t	rates[12];
+	uint8_t	rates[15];
 } __packed;
 /* structure for command IWI_CMD_SET_TX_POWER */

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