From 1c25bfad93e69ce13f744a2fb919f02ea396a985 Mon Sep 17 00:00:00 2001 From: Zhao Li Date: Tue, 25 Aug 2026 19:25:23 +0800 Subject: [PATCH] wifi: mwifiex: validate action frame fixed fields mwifiex_process_mgmt_packet() accepts an rx_pkt_length as small as a four-address struct ieee80211_hdr plus the two-byte firmware length prefix. After stripping the prefix, mwifiex_parse_mgmt_packet() can receive a frame equal to sizeof(struct ieee80211_hdr). For action frames, the parser reads the category byte immediately after that header and, for a public action frame, reads the following action code byte without verifying that either field is present. A truncated frame can therefore make the parser consume up to two bytes past the firmware-declared frame length. If those bytes look like a TDLS discovery response, the malformed frame can spuriously update peer signal state. Require the category and public action-code fields before reading them. Use sizeof(*ieee_hdr) so the checks and field accesses directly match the firmware four-address layout being parsed before address4 is removed. Suggested-by: Johannes Berg Suggested-by: Brian Norris Fixes: 72e5aa8d2a6d ("mwifiex: support for parsing TDLS discovery frames") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/66f148d83eb9f0970b9abbccc85d1b61244e54ad.camel@sipsolutions.net/ Link: https://lore.kernel.org/all/20260708195911.84365-8-enderaoelyther@gmail.com/ Link: https://lore.kernel.org/all/20260723011013.76968-1-enderaoelyther@gmail.com/ Link: https://lore.kernel.org/all/20260723202257.688-1-enderaoelyther@gmail.com/ Link: https://lore.kernel.org/all/anuWyiPQja6_5vly@google.com/ Assisted-by: Codex:gpt-5 Assisted-by: Kimi:K3 Signed-off-by: Zhao Li Link: https://patch.msgid.link/20260825112523.95774-1-enderaoelyther@gmail.com Signed-off-by: Johannes Berg --- drivers/net/wireless/marvell/mwifiex/util.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/marvell/mwifiex/util.c b/drivers/net/wireless/marvell/mwifiex/util.c index 7d3631d21223..71305efb77ac 100644 --- a/drivers/net/wireless/marvell/mwifiex/util.c +++ b/drivers/net/wireless/marvell/mwifiex/util.c @@ -317,10 +317,16 @@ mwifiex_parse_mgmt_packet(struct mwifiex_private *priv, u8 *payload, u16 len, switch (stype) { case IEEE80211_STYPE_ACTION: - category = *(payload + sizeof(struct ieee80211_hdr)); + if (len < sizeof(*ieee_hdr) + 1) + return -1; + + category = *(payload + sizeof(*ieee_hdr)); switch (category) { case WLAN_CATEGORY_PUBLIC: - action_code = *(payload + sizeof(struct ieee80211_hdr) + if (len < sizeof(*ieee_hdr) + 2) + return -1; + + action_code = *(payload + sizeof(*ieee_hdr) + 1); if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) { addr2 = ieee_hdr->addr2;