From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dispatch1-us1.ppe-hosted.com (dispatch1-us1.ppe-hosted.com [148.163.129.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B73939FCB4 for ; Wed, 11 Mar 2026 23:08:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.129.49 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773270483; cv=none; b=eiL4W1Vhy+UWyRy0zRh6XBbSViFz4vEDI0BJmer5sfekbUzu8zn2VSftuAUtaTKKlcMYV47KQgEzaNZLGX6MVaOBWoUFx8FMbmvehs69eLpJI+EM4SCUqJQFhgZHM/6bulPiUv02jcuLAz/N90uOUrqOOAU88mPR0BhZfnSaZVk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773270483; c=relaxed/simple; bh=CTCMuoNTR1zKOuUeLRCwrEf946YXF/gSoMHht7voBy0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=L8OqoB89PauN3VM0FVSxB97DQa63Sux/1QFLH3VENmIfO4Yt0uzl8WOUvYcUDRldGlFZAz/HvhMMcLet4Pmax77cNiyR5AAh2pg0XmpmMHTN8EaaytFLPsgSAXAUZLd7RG4GzpFVE+EZ54vwo92YpIoD4oDUBxwfss5/eExa7dU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=candelatech.com; spf=pass smtp.mailfrom=candelatech.com; dkim=pass (1024-bit key) header.d=candelatech.com header.i=@candelatech.com header.b=SxNsKkU3; arc=none smtp.client-ip=148.163.129.49 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=candelatech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=candelatech.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=candelatech.com header.i=@candelatech.com header.b="SxNsKkU3" Received: from dispatch1-us1.ppe-hosted.com (ip6-localhost [127.0.0.1]) by dispatch1-us1.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTP id 557632C00A7 for ; Wed, 11 Mar 2026 23:07:49 +0000 (UTC) X-Virus-Scanned: Proofpoint Essentials engine Received: from mail3.candelatech.com (mail.candelatech.com [208.74.158.173]) by mx1-us1.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTP id 817D4A80075 for ; Wed, 11 Mar 2026 23:07:42 +0000 (UTC) Received: from ben-dt5.candelatech.com (firewall.candelatech.com [50.251.239.81]) by mail3.candelatech.com (Postfix) with ESMTP id AEDB913C2B3; Wed, 11 Mar 2026 16:07:39 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 mail3.candelatech.com AEDB913C2B3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=candelatech.com; s=default; t=1773270459; bh=CTCMuoNTR1zKOuUeLRCwrEf946YXF/gSoMHht7voBy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SxNsKkU3g3XNwILV2A8qGc3gFk1ZCcGq0B7MAFFotBZO7djG/xnPIOXYdQofiRjlS u6qcjro6ih0hC2mQpqEuYx0wNFWrFF5EUxbs0tuf4iMyfoHmo3G53hTx/oCJw8JzrL SDJqHMhpYLimmJdatxYqIo0JxzzubPcjbvgSBO74= From: greearb@candelatech.com To: linux-wireless@vger.kernel.org Cc: Ben Greear Subject: [PATCH wireless-next 15/28] wifi: iwlwifi: mld: Fix use-after-free of bss_conf Date: Wed, 11 Mar 2026 16:07:17 -0700 Message-ID: <20260311230730.163348-16-greearb@candelatech.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20260311230730.163348-1-greearb@candelatech.com> References: <20260311230730.163348-1-greearb@candelatech.com> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-MDID: 1773270463-0c15Q_QVrwEM X-PPE-STACK: {"stack":"us5"} X-MDID-O: us5;ut7;1773270463;0c15Q_QVrwEM;;f7146c1849a4b08a52804beb1c1cdf45 X-PPE-TRUSTED: V=1;DIR=OUT; From: Ben Greear In certain failure paths, the driver is not fully configured, and it fails to find the link object. We still need to remove pointers to the bss_conf to keep from crashing shortly afterwards. Search all indices for stale pointer if we cannot do the fast lookup by ID. Signed-off-by: Ben Greear --- drivers/net/wireless/intel/iwlwifi/mld/link.c | 42 +++++++++++++++---- 1 file changed, 34 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mld/link.c b/drivers/net/wireless/intel/iwlwifi/mld/link.c index b5430e8a73d6..1e4959ceb3db 100644 --- a/drivers/net/wireless/intel/iwlwifi/mld/link.c +++ b/drivers/net/wireless/intel/iwlwifi/mld/link.c @@ -504,23 +504,49 @@ void iwl_mld_remove_link(struct iwl_mld *mld, struct iwl_mld_vif *mld_vif = iwl_mld_vif_from_mac80211(bss_conf->vif); struct iwl_mld_link *link = iwl_mld_link_from_mac80211(bss_conf); bool is_deflink = link == &mld_vif->deflink; - u8 fw_id = link->fw_id; + u16 fw_id; - if (WARN_ON(!link || link->active)) - return; + if (WARN_ON_ONCE(!link)) { + IWL_ERR(mld, "Remove nonexistent link, bss_conf: 0x%px link-id: %d\n", + bss_conf, bss_conf->link_id); + fw_id = 0xffff; + } else { + fw_id = link->fw_id; + } + + /* Not cleaning it up seems worse than cleaning up an active link, + * so continue on even in warning case. + */ + if (link && WARN_ON_ONCE(link->active)) + IWL_ERR(mld, "Removing active link, id: %d\n", + bss_conf->link_id); iwl_mld_rm_link_from_fw(mld, bss_conf); /* Continue cleanup on failure */ - if (!is_deflink) + if (link && !is_deflink) kfree_rcu(link, rcu_head); + rcu_read_lock(); RCU_INIT_POINTER(mld_vif->link[bss_conf->link_id], NULL); - if (WARN_ON(fw_id >= mld->fw->ucode_capa.num_links)) - return; - - RCU_INIT_POINTER(mld->fw_id_to_bss_conf[fw_id], NULL); + if (fw_id >= mld->fw->ucode_capa.num_links) { + struct ieee80211_bss_conf *tmp_bss_conf; + int i; + + /* Search for any existing back-pointer */ + for (i = 0; i < ARRAY_SIZE(mld->fw_id_to_bss_conf); i++) { + tmp_bss_conf = rcu_dereference(mld->fw_id_to_bss_conf[i]); + if (tmp_bss_conf == bss_conf) { + IWL_ERR(mld, "WARNING: Found bss_conf in fw_id_to_bss_conf[%i], Nulling pointer.\n", + i); + RCU_INIT_POINTER(mld->fw_id_to_bss_conf[i], NULL); + } + } + } else { + RCU_INIT_POINTER(mld->fw_id_to_bss_conf[fw_id], NULL); + } + rcu_read_unlock(); } void iwl_mld_handle_missed_beacon_notif(struct iwl_mld *mld, -- 2.42.0