5ee58d7e6a
The minstrel rate controller periodically looks up rate indexes in a sampling table. When accessing a specific row and column, minstrel correctly does a bounds check which, on the surface, appears to handle the case where mi->n_rates < 2. However, mi->sample_idx is actually defined as an unsigned, so the right hand side is taken to be a huge positive number when negative, and the check will always fail. Consequently, the RC will overrun the array and cause random memory corruption when communicating with a peer that has only a single rate. The max value of mi->sample_idx is around 25 so casting to int should have no ill effects. Without the change, uptime is a few minutes under load with an AP that has a single hard-coded rate, and both the AP and STA could potentially crash. With the change, both lasted 12 hours with a steady load. Thanks to Ognjen Maric for providing the single-rate clue so I could reproduce this. This fixes http://bugzilla.kernel.org/show_bug.cgi?id=12490 on the regression list (also http://bugzilla.kernel.org/show_bug.cgi?id=13000). Cc: stable@kernel.org Reported-by: Sergey S. Kostyliov <rathamahata@gmail.com> Reported-by: Ognjen Maric <ognjen.maric@gmail.com> Signed-off-by: Bob Copeland <me@bobcopeland.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> |
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9p | ||
802 | ||
8021q | ||
appletalk | ||
atm | ||
ax25 | ||
bluetooth | ||
bridge | ||
can | ||
core | ||
dcb | ||
dccp | ||
decnet | ||
dsa | ||
econet | ||
ethernet | ||
ieee802154 | ||
ipv4 | ||
ipv6 | ||
ipx | ||
irda | ||
iucv | ||
key | ||
lapb | ||
llc | ||
mac80211 | ||
netfilter | ||
netlabel | ||
netlink | ||
netrom | ||
packet | ||
phonet | ||
rds | ||
rfkill | ||
rose | ||
rxrpc | ||
sched | ||
sctp | ||
sunrpc | ||
tipc | ||
unix | ||
wanrouter | ||
wimax | ||
wireless | ||
x25 | ||
xfrm | ||
compat.c | ||
Kconfig | ||
Makefile | ||
nonet.c | ||
socket.c | ||
sysctl_net.c | ||
TUNABLE |