[PATCH 3.4 31/43] radiotap: fix bitmap-end-finding buffer overrun

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



3.4-stable review patch.  If anyone has any objections, please let me know.

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

From: Johannes Berg <johannes.berg@xxxxxxxxx>

commit bd02cd2549cfcdfc57cb5ce57ffc3feb94f70575 upstream.

Evan Huus found (by fuzzing in wireshark) that the radiotap
iterator code can access beyond the length of the buffer if
the first bitmap claims an extension but then there's no
data at all. Fix this.

Reported-by: Evan Huus <eapache@xxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/wireless/radiotap.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/net/wireless/radiotap.c
+++ b/net/wireless/radiotap.c
@@ -122,6 +122,10 @@ int ieee80211_radiotap_iterator_init(
 	/* find payload start allowing for extended bitmap(s) */
 
 	if (iterator->_bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT)) {
+		if ((unsigned long)iterator->_arg -
+		    (unsigned long)iterator->_rtheader + sizeof(uint32_t) >
+		    (unsigned long)iterator->_max_length)
+			return -EINVAL;
 		while (get_unaligned_le32(iterator->_arg) &
 					(1 << IEEE80211_RADIOTAP_EXT)) {
 			iterator->_arg += sizeof(uint32_t);


--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]