From nobody Thu Oct 2 04:50:33 2025 Received: from mail-wr1-f44.google.com (mail-wr1-f44.google.com [209.85.221.44]) (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 3BB74286D70 for ; Tue, 23 Sep 2025 11:20:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.44 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758626422; cv=none; b=R7SZOxXo8raOWnqhbsOJS6t3P+ebB/zh28YoZo3+lUlr0HyEFVpTYAiIfmYfk8+k/BL1FVkC4Ugau8RnsohWfFaarq2QjM3iPrOW/OH6roVP+GerNS2SgJ7XC9DvdPs3x5OLCEQLSYkusafrCmNvPh8BYDYi4gVXll3FV6fGDzU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758626422; c=relaxed/simple; bh=B3fRnPBrL6bndjkV80Lqpltt+HotD1WV25scPuVekdg=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition; b=ACgJkJbWGqYjiUbqdzwE5WcQTvZNb9GbJJWybMOSuAdEfMZMV1Nun9LJpAOtpSaEWmRdREl7JFAS4UimAOeGXdTThxrIBZ2/DxJxMrIPhyf0va10lBzPWYmYrToM/4HW+Wk8ULOd0e+gJn/eVmbE96kwkpAdv2Dl06pP7tye8i4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=i9wGKFr7; arc=none smtp.client-ip=209.85.221.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="i9wGKFr7" Received: by mail-wr1-f44.google.com with SMTP id ffacd0b85a97d-3ee12a63af1so2402293f8f.1 for ; Tue, 23 Sep 2025 04:20:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1758626420; x=1759231220; darn=vger.kernel.org; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :from:to:cc:subject:date:message-id:reply-to; bh=VE8TJpb+bgJUe79vS/3A1j4fTVnXxc+D4cm6eCdCSiM=; b=i9wGKFr73N2dpnTDqR9wl7Mt41sJLnKWB/19jvnsgxsw0sbDnRHDjb9jZl8xTNBqzL x3TIaMnHjMFQQQFTAyc7M/sHlm46TalPo3ChDHoDyqlgeBXSHRM+QOgnjsuM66Mi4CWy FQ2n36iX7uVW2bULH7g2idNd5B7WNUoC1qn6dqmc/SzdtltQ91bO8OvenQqWTcy6bufn UX3yLGMlmsWHTK4McIGcmRrNUtGpJfj8AVHbKFSmDkILr9Ur9eE9aB/QiaxpfZixxBGF si7jWMjtCkB41RA96YLkY9KRzv8IAIzjYupmAgc9DADqGItAIpTUlNlJ1/1cv3ii41wp FAFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758626420; x=1759231220; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=VE8TJpb+bgJUe79vS/3A1j4fTVnXxc+D4cm6eCdCSiM=; b=Z/6J2oKaG8RuEqq82osL7hBcZZox8K04qQ+SCsACQe+NipuU1tLNrmyHxLDf2p0ss5 BsFrBZIUb5eaa5YIsyZiJ92+H8gd8UzgTrCD9p/iJ33Wo0AW7m1BbQE2OiM1O5TXGRe7 TYXK8MUMgzmTJ9cioHtxWE2fAPLdmDi6a38h3/WsgFWgo75P3YPzAqAXUwcJy37OnZMx Qa2JMdBEH34+7ZuV6YwFoclKfDs608WtOOgHdZcg7ZoF5L14/kme2ATMwrqVFPp04byT kUcoQjntvGD6VdTENKejQ31sddvb6ej74Q6Ap1/BpxXSz/ivel3W90O4KYTo7BK8h6bO oWxw== X-Forwarded-Encrypted: i=1; AJvYcCW070k43f3sGp3s3feX2LJnCpXHCk2HO7hvOn2JHvn3iiinu8x9ADAZCzwGDEshF2tRR5H0nhyt1CwF8Bg=@vger.kernel.org X-Gm-Message-State: AOJu0Yy2qzEmWDDfn4sNjjmwKaguH+4nfdqV4lDRXxlAfgEFVNz1O4r4 z8+ZFIu/+gLqn2Adhq3NM0YD1s42bOVvjhenqKYaO18CoIeHbrZEPO+IYSCgItSnJ6E= X-Gm-Gg: ASbGncuxW25/vwuuAA49P9yuf9Wl43JFHxDK97cFK7Eb4l7aaJMLGwMcxpeFTZcFFXE uDLI7lYO+cgpKRdRjfZlvIHK/TsstTWUCGhvmowtz9qFNMmVyFArQjMMgc05dcZh4+lDsdgcr76 Jc+dCmt52cmtX8S2GwM4+qJEQUvytKseJ+W7Bmy3Xx195gLSldHfk3fTQr08oHJ5/itdLfXT5jE g1l8t1ZHbLV+WvCCDuqXCKP9k3W7Q7IWWChkRUhU819UHyVbPlLQa4Xpvb9jnMTl8LjuuZfpMlL KBaUv367TO4+AFeosm24IzqlKAt4/5iEZm043XpPQlenOdb2oIrDCGmJE4VMvZpPArDoqGZL0RA iIq3UWyWehjGc/aZMFqRdmc2UVI82 X-Google-Smtp-Source: AGHT+IH5ERjqItScX3GlaqMEPRqH6OH857XNBhEBSVVCeFpYjz1uRmIbad/KOH3nGEJlbG/jtig3mw== X-Received: by 2002:a05:6000:186d:b0:3e7:46bf:f8bd with SMTP id ffacd0b85a97d-405c5ccd210mr1652472f8f.23.1758626419495; Tue, 23 Sep 2025 04:20:19 -0700 (PDT) Received: from localhost ([196.207.164.177]) by smtp.gmail.com with UTF8SMTPSA id 5b1f17b1804b1-464f0d8a2bfsm249409455e9.2.2025.09.23.04.20.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Sep 2025 04:20:19 -0700 (PDT) Date: Tue, 23 Sep 2025 14:20:16 +0300 From: Dan Carpenter To: Miri Korenblit Cc: Johannes Berg , Emmanuel Grumbach , Somashekhar Puttagangaiah , Pagadala Yesu Anjaneyulu , Daniel Gabay , Avraham Stern , Shaul Triebitz , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH] wifi: iwlwifi: fix potential use after free in iwl_mld_remove_link() Message-ID: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline X-Mailer: git-send-email haha only kidding Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 --- 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/wi= reless/intel/iwlwifi/mld/link.c index 738f80fe0c50..60d814bf5779 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 =3D iwl_mld_vif_from_mac80211(bss_conf->vif); struct iwl_mld_link *link =3D iwl_mld_link_from_mac80211(bss_conf); bool is_deflink =3D link =3D=3D &mld_vif->deflink; + u8 fw_id =3D link->fw_id; =20 if (WARN_ON(!link || link->active)) return; @@ -513,10 +514,10 @@ void iwl_mld_remove_link(struct iwl_mld *mld, =20 RCU_INIT_POINTER(mld_vif->link[bss_conf->link_id], NULL); =20 - if (WARN_ON(link->fw_id >=3D mld->fw->ucode_capa.num_links)) + if (WARN_ON(fw_id >=3D mld->fw->ucode_capa.num_links)) return; =20 - 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); } =20 void iwl_mld_handle_missed_beacon_notif(struct iwl_mld *mld, --=20 2.51.0