From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ED992C43458 for ; Wed, 1 Jul 2026 01:09:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=7HlLa5ZFr16KNcTsaTNAJ5bA9P3jnXoKjhSCLJyTnxc=; b=c3wRylVL5LleB9dJQ9C7sf4FsV ApLvwGXG3rc+ERYDATNcsHCNJpaiKMBKUxxrO1e4CTNumR3cX3dkbJ3+1tvN3M0K+Tr5gQwIPqcgs fRAC/lMffVKDq1ENB5fzxRcDZPMlR+Fpp8EbGflqjvM3NM+CjLYtvRQkDy9jyjB+J5m+lK+pANMtb /yyY6ju7kgsLEDVhMp7fqvD9dCE0OqUFqvkBSe6skr+2nj86XlhaECPeAx3OP0J0u6h5Bimta5mar NoUc/fTkH15rSwObYr+rwbZRIiTSmtyI/1iVwnzB9iO4l+DDouYs1fkKXT/HvtAVk9iorELrE+ns+ neR1v16Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wejSM-00000000RIl-399z; Wed, 01 Jul 2026 01:09:38 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wejSJ-00000000RIO-3uOV for linux-mediatek@lists.infradead.org; Wed, 01 Jul 2026 01:09:37 +0000 X-UUID: 8441fc4674e911f1acbe4559397dec65-20260630 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=7HlLa5ZFr16KNcTsaTNAJ5bA9P3jnXoKjhSCLJyTnxc=; b=WhHhqtmv87Luuo/IomRQ4VaIOfDYMINBbSYLEFT95dX71pzaUnHkvTBGLwuMootCpNMVfOtYaa7hpkCYiVlk5Z22wpfVjz7S80aikJzSWznvzq51ZpoqnLEUQc9SIi5CpjGAHRGdmomTtydDvObTajaLufw4wJ8E9DQ6V2imx2k=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.17,REQID:0497245e-f69a-40ec-a92a-2adf05b5755b,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:d497b38,CLOUDID:d188d881-6310-4e6b-a6b1-aca20d98ed8b,B ulkID:nil,BulkQuantity:0,SF:102|836|865|888|898,TC:-5,Content:0|15|50|99,E DM:-3,IP:nil,URL:0,File:130,RT:0,Bulk:nil,QS:nil,BEC:-1,COL:0,OSI:0,OSA:0, AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 8441fc4674e911f1acbe4559397dec65-20260630 Received: from mtkmbs10n1.mediatek.inc [(172.21.101.34)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 521301154; Tue, 30 Jun 2026 18:09:32 -0700 Received: from mtkmbs13n2.mediatek.inc (172.21.101.108) by MTKMBS09N1.mediatek.inc (172.21.101.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.29; Wed, 1 Jul 2026 09:09:29 +0800 Received: from mtksitap99.mediatek.inc (10.233.130.16) by mtkmbs13n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.2562.29 via Frontend Transport; Wed, 1 Jul 2026 09:09:29 +0800 From: Eason Lai To: , CC: , , , , , , , , , , , , Eason Lai Subject: [PATCH v6 1/1] wifi: mt76: mt792x: fix use-after-free in mt76_rx_poll_complete Date: Wed, 1 Jul 2026 09:06:54 +0800 Message-ID: <20260701010654.956863-1-eason.lai@mediatek.com> X-Mailer: git-send-email 2.45.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260630_180936_050847_B87353CC X-CRM114-Status: GOOD ( 14.25 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org From: Eason Lai A use-after-free issue occurs in mt76_rx_poll_complete due to a race condition. The STA has already been removed, but the rx_status still had a pointer to the wcid in the STA. Set the links' wcid pointers to be NULL for a MLD in mt7925_sta_pre_rcu_remove() BUG: KASAN: invalid-access in mt76_rx_poll_complete+0x280/0x470 Call trace: dump_backtrace+0xec/0x128 show_stack+0x18/0x28 dump_stack_lvl+0x40/0xc8 print_report+0x1b8/0x710 kasan_report+0xe0/0x144 do_bad_area+0x120/0x260 do_tag_check_fault+0x20/0x34 do_mem_abort+0x54/0xa8 el1_abort+0x3c/0x5c el1h_64_sync_handler+0x40/0xcc el1h_64_sync+0x7c/0x80 mt76_rx_poll_complete+0x280/0x470 mt76_dma_rx_poll+0x114/0x51c mt792x_poll_rx+0x60/0xf8 napi_threaded_poll_loop+0xe0/0x450 napi_threaded_poll+0x80/0x9c kthread+0x11c/0x158 ret_from_fork+0x10/0x20 Fixes: c948b5da6bbe ("wifi: mt76: mt7925: add Mediatek Wi-Fi7 driver for mt7925 chips") Signed-off-by: Eason Lai --- v2: fix mt76x02 build errors v3: fix mt76x02 build error due to variable set but not used v4: fix use-after-free in MLO v5: correct commit message v6: correct commit message --- .../net/wireless/mediatek/mt76/mt7925/main.c | 36 ++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/main.c b/drivers/net/wireless/mediatek/mt76/mt7925/main.c index 73d3722739d0..e3fb6392eda2 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7925/main.c +++ b/drivers/net/wireless/mediatek/mt76/mt7925/main.c @@ -2410,6 +2410,40 @@ static void mt7925_channel_switch_rx_beacon(struct ieee80211_hw *hw, } } +static void mt7925_sta_pre_rcu_remove(struct ieee80211_hw *hw, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta) +{ + struct mt76_phy *phy = hw->priv; + struct mt76_dev *dev = phy->dev; + struct mt76_wcid *wcid = (struct mt76_wcid *)sta->drv_priv; + + mutex_lock(&dev->mutex); + spin_lock_bh(&dev->status_lock); + + if (ieee80211_vif_is_mld(vif)) { + struct mt792x_sta *msta = (struct mt792x_sta *)sta->drv_priv; + struct mt792x_vif *mvif = (struct mt792x_vif *)vif->drv_priv; + unsigned long valid = mvif->valid_links; + struct mt792x_link_sta *mlink; + unsigned int link_id; + + for_each_set_bit(link_id, &valid, IEEE80211_MLD_MAX_NUM_LINKS) { + mlink = mt792x_sta_to_link(msta, link_id); + if (!mlink || !mlink->wcid.sta) + continue; + if (mlink->wcid.idx < ARRAY_SIZE(dev->wcid)) + rcu_assign_pointer(dev->wcid[mlink->wcid.idx], + NULL); + } + } else { + rcu_assign_pointer(dev->wcid[wcid->idx], NULL); + } + + spin_unlock_bh(&dev->status_lock); + mutex_unlock(&dev->mutex); +} + const struct ieee80211_ops mt7925_ops = { .tx = mt792x_tx, .start = mt7925_start, @@ -2422,7 +2456,7 @@ const struct ieee80211_ops mt7925_ops = { .start_ap = mt7925_start_ap, .stop_ap = mt7925_stop_ap, .sta_state = mt76_sta_state, - .sta_pre_rcu_remove = mt76_sta_pre_rcu_remove, + .sta_pre_rcu_remove = mt7925_sta_pre_rcu_remove, .set_key = mt7925_set_key, .sta_set_decap_offload = mt7925_sta_set_decap_offload, #if IS_ENABLED(CONFIG_IPV6) -- 2.45.2