tree d6737b2b810710bf267174dde547b1a01592edab
parent 9f775ead5e570e7e19015b9e4e2f3dd6e71a5935
author Peng Xu <pxu@qti.qualcomm.com> 1507062111 +0300
committer Johannes Berg <johannes.berg@intel.com> 1507120761 +0200

nl80211: Define policy for packet pattern attributes

Define a policy for packet pattern attributes in order to fix a
potential read over the end of the buffer during nla_get_u32()
of the NL80211_PKTPAT_OFFSET attribute.

Note that the data there can always be read due to SKB allocation
(with alignment and struct skb_shared_info at the end), but the
data might be uninitialized. This could be used to leak some data
from uninitialized vmalloc() memory, but most drivers don't allow
an offset (so you'd just get -EINVAL if the data is non-zero) or
just allow it with a fixed value - 100 or 128 bytes, so anything
above that would get -EINVAL. With brcmfmac the limit is 1500 so
(at least) one byte could be obtained.

Cc: stable@kernel.org
Signed-off-by: Peng Xu <pxu@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[rewrite description based on SKB allocation knowledge]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>