From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793881287; b=vZup4IRakbHo2nVh7OCVMdheOEJnge7+jWRHXEMi3EgUiBTK10T2I+dz8u6LTY+MieT3 WqvKaUuSiVuCRbmn2/iGWs0WteL8phQkbATKZjAarj7UvHE1j57qnSLGAzCB6+A6dkTIj 8sICL1YS65cuCzH3Og0mWnGdfQnTO5jBahBii4XGsTQfMYlq0WXLV5UWZE6ojyi65x6GG F9PXfi7d3c+ysxfWgX8I/KkVxoEdeO5hZClo1ZdTjBFeoBhu8KOOkBrPbyWywzoTGB61P LIaZ4J3LdHyBzVSq0G/eRW1WKh/RuzKwOe2y6rOWxrkwG1o7+42z87vqn8eOMO2BBhg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793881287; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=UxiTS62BtQTEaQsj2KqI71K0t2BbsWQA2HZrTm2lC8k=; b=BMIsvdiaVKgAOlcDzLcpkRXbeoHLjTGNctKEEc1Slkg2mG9oFlD6YlO0EjLBVioW9S59 jSy5vBrhT39FHE4/pi9QVpfad/0B3y4+TA28kvKtzmFZg+5+o+voHHsiBjalhQkraZtT/ Jgh3TyexrW8+8svUQqBhM2G0mx6GVG71NAdRZ+Dg1gud3MGgBrlVU4vkSQ7VTKlonJ6h+ 3EwGmPFv6Bl0ugGf80bq5VT2LAJGxOxW8ePj8fQaVUAgQZec+c/QE6P8YCx33vj3f9IdX jB25xTdZlOzduVfVEzkSOTQ/jDMfWRzyaRXiBJy1mrUosacni/GHG7Bigdl29SqI24g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=MFYAVIqM; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1DC62606D82A for ; Thu, 5 Nov 2026 12:21:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=MFYAVIqM Received: by smtp.kernel.org (Postfix) with ESMTPSA id 457A21F00919; Thu, 5 Nov 2026 12:21:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793881286; bh=UxiTS62BtQTEaQsj2KqI71K0t2BbsWQA2HZrTm2lC8k=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MFYAVIqMJ3nq+Zl+IqmxwuDj1LF3clDz5O0TlBLcdVxD98SSdeDiKVUJ3RvmSBi4o IStqTYPFDMc2Oor39Vuz0OC9xBepE9MCQfGyBofdRY1fnGe5gk0mrlXJKmOVQwxANo rxH8YIs1RZpv2bCHE1PYzenw6FbY2EhLUji9PMb3nRnYLKZV+3R+NPL6dOcrc5OUaz jkxp1Agv/hgj7w5qfHpjF2wKcXb4PI5H7LbwjR4iOvPitD7pIDTVhv+Ku2LWLzMP0+ qObt5ENwC5SzKR2kVoA5+mVre8OA4o+u19obXhpEciOn5um49Q5nghzIezryNoYkTY JhCD/qNdJB2zA== From: Sasha Levin To: stable@vger.kernel.org Cc: Tianchu Chen , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 5.10.y] staging: rtl8723bs: fix protected RX frame validation in decrypt path Date: Thu, 5 Nov 2026 07:21:25 -0500 Message-ID: <20261105121915.1233786-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026110449-unleveled-simmering-935a@gregkh> References: <2026110449-unleveled-simmering-935a@gregkh> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Tianchu Chen [ Upstream commit 495cb31c791bdf3f9efef255a9587b05b0526c9d ] The RX software decrypt path mishandles crafted protected frames from a malicious AP in two ways: 1) decryptor() never checks that a protected frame is long enough to hold the 802.11 header plus the per-cipher trailer. All of rtw_wep_decrypt(), rtw_tkip_decrypt() and rtw_aes_decrypt() compute length = hdr.len - hdrlen - iv_len; and act on the result, and recvframe_chkmic() similarly computes datalen = hdr.len - hdrlen - iv_len - icv_len - 8; for TKIP (the 8-byte Michael MIC is not accounted for in icv_len). A frame shorter than hdrlen + iv_len + icv_len (+ 8 for TKIP) underflows these unsigned subtractions, turning into a ~4 GiB iteration count in aes_decipher()/arc4_crypt()/rtw_seccalctkipmic() or a ~4 GiB crc32_le() length, causing out-of-bounds reads/writes of up to ~4 GiB starting from the rx skb. Reject such frames in decryptor() before touching the IV; this covers all three ciphers and the TKIP MIC check, and also keeps the unconditional iv[3] access within the frame. 2) validate_80211w_mgmt() keeps using the frame - two memcpys through the stale rx_data pointer and a pkt_len update - before checking whether decryptor() returned NULL. On decrypt failure (e.g. a unicast protected deauth/disassoc/action frame with a bad MIC, which this path always software-decrypts) the skb has already been freed, so this is a use-after-free read/write, and the caller's error path frees the frame a second time, drifting free_recvframe_cnt. Bail out immediately when decryptor() fails, freeing the temporary mgmt_DATA buffer first. Discovered by Atuin - Automated Vulnerability Discovery Engine. Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver") Assisted-by: LLM Cc: stable@vger.kernel.org Signed-off-by: Tianchu Chen Link: https://patch.msgid.link/8ee3bdd1c45034200cb1aa9a7e9b575b9584643a@linux.dev Signed-off-by: Greg Kroah-Hartman [ sashal: Retained the existing DBG_871X() debug message in the relocated decrypt-failure branch. ] Signed-off-by: Sasha Levin --- drivers/staging/rtl8723bs/core/rtw_recv.c | 25 ++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/drivers/staging/rtl8723bs/core/rtw_recv.c b/drivers/staging/rtl8723bs/core/rtw_recv.c index 0e6fb03ff85c8..8ed6ded1bef79 100644 --- a/drivers/staging/rtl8723bs/core/rtw_recv.c +++ b/drivers/staging/rtl8723bs/core/rtw_recv.c @@ -451,7 +451,21 @@ union recv_frame *decryptor(struct adapter *padapter, union recv_frame *precv_fr RT_TRACE(_module_rtl871x_recv_c_, _drv_info_, ("prxstat->decrypted =%x prxattrib->encrypt = 0x%03x\n", prxattrib->bdecrypted, prxattrib->encrypt)); if (prxattrib->encrypt > 0) { - u8 *iv = precv_frame->u.hdr.rx_data+prxattrib->hdrlen; + u8 *iv; + u32 min_len = prxattrib->hdrlen + prxattrib->iv_len + prxattrib->icv_len; + + /* TKIP appends an 8-byte Michael MIC that icv_len doesn't account for */ + if (prxattrib->encrypt == _TKIP_) + min_len += 8; + + /* a protected frame must be long enough to hold the IV and ICV/MIC */ + if (precv_frame->u.hdr.len < min_len) { + rtw_free_recvframe(precv_frame, + &padapter->recvpriv.free_recv_queue); + return NULL; + } + + iv = precv_frame->u.hdr.rx_data + prxattrib->hdrlen; prxattrib->key_index = (((iv[3])>>6)&0x3); if (prxattrib->key_index > WEP_KEYS) { @@ -1426,6 +1440,11 @@ static sint validate_80211w_mgmt(struct adapter *adapter, union recv_frame *prec goto validate_80211w_fail; } precv_frame = decryptor(adapter, precv_frame); + if (!precv_frame) { + kfree(mgmt_DATA); + DBG_871X("%s mgmt descrypt fail !!!!!!!!!\n", __func__); + goto validate_80211w_fail; + } /* save actual management data frame body */ memcpy(mgmt_DATA, ptr+pattrib->hdrlen+pattrib->iv_len, data_len); /* overwrite the iv field */ @@ -1433,10 +1452,6 @@ static sint validate_80211w_mgmt(struct adapter *adapter, union recv_frame *prec /* remove the iv and icv length */ pattrib->pkt_len = pattrib->pkt_len - pattrib->iv_len - pattrib->icv_len; kfree(mgmt_DATA); - if (!precv_frame) { - DBG_871X("%s mgmt descrypt fail !!!!!!!!!\n", __func__); - goto validate_80211w_fail; - } } else if (IS_MCAST(GetAddr1Ptr(ptr)) && (subtype == WIFI_DEAUTH || subtype == WIFI_DISASSOC)) { sint BIP_ret = _SUCCESS; -- 2.53.0