cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES

validate_scan_freqs() retrieves frequencies from attributes
nested in the attribute NL80211_ATTR_SCAN_FREQUENCIES with
nla_get_u32(), which reads 4 bytes from each attribute
without validating the size of data received. Attributes
nested in NL80211_ATTR_SCAN_FREQUENCIES don't have an nla policy.

Validate size of each attribute before parsing to avoid potential buffer
overread.

Fixes: 2a51931192 ("cfg80211/nl80211: scanning (and mac80211 update to use it)")
Cc: stable@vger.kernel.org
Signed-off-by: Srinivas Dasari <dasaris@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Srinivas Dasari 2017-07-07 01:43:42 +03:00 committed by Johannes Berg
parent 8feb69c7bd
commit d7f13f7450
1 changed files with 4 additions and 0 deletions

View File

@ -6469,6 +6469,10 @@ static int validate_scan_freqs(struct nlattr *freqs)
struct nlattr *attr1, *attr2;
int n_channels = 0, tmp1, tmp2;
nla_for_each_nested(attr1, freqs, tmp1)
if (nla_len(attr1) != sizeof(u32))
return 0;
nla_for_each_nested(attr1, freqs, tmp1) {
n_channels++;
/*