wifi: mac80211_hwsim: reject undersized HWSIM_ATTR_TX_INFO

hwsim_tx_info_frame_received_nl() casts the HWSIM_ATTR_TX_INFO payload
to a struct hwsim_tx_rate * and unconditionally reads
IEEE80211_TX_MAX_RATES entries (8 bytes) from it. The policy only bounds
the attribute from above (NLA_BINARY .len is a maximum) and the op sets
GENL_DONT_VALIDATE_STRICT, so a short or zero-length attribute is
accepted and the loop reads past the payload.

Require the exact length in the policy, so a malformed attribute is
rejected before the handler runs.

Signed-off-by: Ibrahim Hashimov <security@auditcode.ai>
Assisted-by: AuditCode-AI:2026.07
Link: https://patch.msgid.link/20260721115346.17236-1-security@auditcode.ai
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Ibrahim Hashimov 2026-07-21 13:53:46 +02:00 committed by Johannes Berg
parent 43b25879f0
commit 3dc723ac78

View File

@ -870,9 +870,9 @@ static const struct nla_policy hwsim_genl_policy[HWSIM_ATTR_MAX + 1] = {
[HWSIM_ATTR_FLAGS] = { .type = NLA_U32 },
[HWSIM_ATTR_RX_RATE] = { .type = NLA_U32 },
[HWSIM_ATTR_SIGNAL] = { .type = NLA_U32 },
[HWSIM_ATTR_TX_INFO] = { .type = NLA_BINARY,
.len = IEEE80211_TX_MAX_RATES *
sizeof(struct hwsim_tx_rate)},
[HWSIM_ATTR_TX_INFO] =
NLA_POLICY_EXACT_LEN(IEEE80211_TX_MAX_RATES *
sizeof(struct hwsim_tx_rate)),
[HWSIM_ATTR_COOKIE] = { .type = NLA_U64 },
[HWSIM_ATTR_CHANNELS] = { .type = NLA_U32 },
[HWSIM_ATTR_RADIO_ID] = { .type = NLA_U32 },