From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 39A4D24BBEB; Tue, 11 Nov 2025 00:51:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762822311; cv=none; b=aGMfnU8pDGFnBs/5Xak/9+RDLj+dMCWTuCEMaw9B2IjQ65gDxvJjSUQYDtWgffbPHpD7BsktHFXK29VfNtVmdrUKdctG6MA3MKApwV3/k7onwCXiLiZ7ThUmgZ4zBJBJPMxQQ/t8BjwB6LzvdI9Ft7QOvlBuy5IrFh9JkWtjxDg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762822311; c=relaxed/simple; bh=fV5qYgE0E6osD/vOd//SOWUE/CjUc0FGrcS0GEwVARI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=niIRM4qTNu4+GPEFLrtBEq+5qHf9Lh6Aonnn+CrRt19J6RNcUfCeYIumGHrqMNP1UUvpI/15C7iHgt74O/GkhY/hpt6QcrnP1CcDK+WD15CeLBdZedGRwu0ygUbbj31djR0jC7tnecuUNldi1fxIAwJ1c3jyzHa+nKDdiXUcn/w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FK7wSi3i; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FK7wSi3i" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8F3CC116B1; Tue, 11 Nov 2025 00:51:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1762822311; bh=fV5qYgE0E6osD/vOd//SOWUE/CjUc0FGrcS0GEwVARI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FK7wSi3ifZmkWsHUUHTGjioyf2O46CfWzPpW01Ahl72bizn7gfJTPdQWIxiBJ71vH p2ypdDnbNGCGXLXVTarVmharOHvQtxVgXSY8phya+v1Cl6bga2ie6aYayXL/I3fbFJ ecL9iOAToTT3lxqi+IFaObXjuTI4Qv00xdGrZKjM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dan Carpenter , Miri Korenblit , Sasha Levin Subject: [PATCH 6.17 037/849] wifi: iwlwifi: fix potential use after free in iwl_mld_remove_link() Date: Tue, 11 Nov 2025 09:33:27 +0900 Message-ID: <20251111004537.339126584@linuxfoundation.org> X-Mailer: git-send-email 2.51.2 In-Reply-To: <20251111004536.460310036@linuxfoundation.org> References: <20251111004536.460310036@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter [ Upstream commit 77e67d5daaf155f7d0f99f4e797c4842169ec19e ] This code frees "link" by calling kfree_rcu(link, rcu_head) and then it dereferences "link" to get the "link->fw_id". Save the "link->fw_id" first to avoid a potential use after free. Fixes: d1e879ec600f ("wifi: iwlwifi: add iwlmld sub-driver") Signed-off-by: Dan Carpenter Link: https://patch.msgid.link/aNKCcKlbSkkS4_gO@stanley.mountain Signed-off-by: Miri Korenblit Signed-off-by: Sasha Levin --- drivers/net/wireless/intel/iwlwifi/mld/link.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mld/link.c b/drivers/net/wireless/intel/iwlwifi/mld/link.c index 782fc41aa1c31..960dcd208f005 100644 --- a/drivers/net/wireless/intel/iwlwifi/mld/link.c +++ b/drivers/net/wireless/intel/iwlwifi/mld/link.c @@ -501,6 +501,7 @@ 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; if (WARN_ON(!link || link->active)) return; @@ -513,10 +514,10 @@ void iwl_mld_remove_link(struct iwl_mld *mld, RCU_INIT_POINTER(mld_vif->link[bss_conf->link_id], NULL); - if (WARN_ON(link->fw_id >= mld->fw->ucode_capa.num_links)) + if (WARN_ON(fw_id >= mld->fw->ucode_capa.num_links)) return; - RCU_INIT_POINTER(mld->fw_id_to_bss_conf[link->fw_id], NULL); + RCU_INIT_POINTER(mld->fw_id_to_bss_conf[fw_id], NULL); } void iwl_mld_handle_missed_beacon_notif(struct iwl_mld *mld, -- 2.51.0