From: Ibrahim Hashimov Date: Tue, 21 Jul 2026 11:53:46 +0000 (+0200) Subject: wifi: mac80211_hwsim: reject undersized HWSIM_ATTR_TX_INFO X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3dc723ac78a6e4fa0fd49e27e487ed319da40a9f;p=thirdparty%2Fkernel%2Flinux.git 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 Assisted-by: AuditCode-AI:2026.07 Link: https://patch.msgid.link/20260721115346.17236-1-security@auditcode.ai Signed-off-by: Johannes Berg --- diff --git a/drivers/net/wireless/virtual/mac80211_hwsim_main.c b/drivers/net/wireless/virtual/mac80211_hwsim_main.c index 956ff9b94526..75caa97becc8 100644 --- a/drivers/net/wireless/virtual/mac80211_hwsim_main.c +++ b/drivers/net/wireless/virtual/mac80211_hwsim_main.c @@ -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 },