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 0B68A1CDFAC; Sun, 7 Sep 2025 20:09:43 +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=1757275783; cv=none; b=FU3MmrkkAD/2K0fG8KPa/tyf3FsaMCOmKfhtrflhdahMPX+3/CbIv+RmNHBL9HsuC426d8R9zIQohnqypBwrSINFnVUJqVnzicymRS7IkSTVVZV67pBb3cooj134TkUR5PESnMWapZjSXQgOLAfQigi0F6+xZ8kU9I5cghoDMLw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757275783; c=relaxed/simple; bh=OD0sTUu25y3+ootuC0lhucnd+FOaovkJMb363jIfOO4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ge3XNkTL6oubCvoG50En7DPtAX2olUjiH2bhzwcP8SOpLSPtZDW9N3hT3UuDTXGiDvDd/kDGTvKuJwNTxGzRBJMWmhe4ePc2g05z9WEeMXkxNArkSZ6HUOaq4bmPUkZ9iKL73eBGaQhPdhACR1UToY5wNCIpx7R3RM4Ea6rMKLc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=D2S11x2X; 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="D2S11x2X" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85B87C4CEF0; Sun, 7 Sep 2025 20:09:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1757275782; bh=OD0sTUu25y3+ootuC0lhucnd+FOaovkJMb363jIfOO4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D2S11x2XxByv0NBPG80f4QPLmAWSBEcMqZ8g6bPmfYrEDrwiF85PHt1ABCNzMqvUo A0SEEbxOapj1Djh943QU1oRtOBPfG5fybn3PN5frUK30bKeORTIJTOuBP4eIz7gE/p nOQ5C0bIi1dbHs50jlq5cTZwCvQs82WiaRZBbCUE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+30754ca335e6fb7e3092@syzkaller.appspotmail.com, Dmitry Antipov , Johannes Berg , Sasha Levin Subject: [PATCH 5.4 02/45] wifi: cfg80211: fix use-after-free in cmp_bss() Date: Sun, 7 Sep 2025 21:57:48 +0200 Message-ID: <20250907195601.029529752@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250907195600.953058118@linuxfoundation.org> References: <20250907195600.953058118@linuxfoundation.org> User-Agent: quilt/0.68 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 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Antipov [ Upstream commit 26e84445f02ce6b2fe5f3e0e28ff7add77f35e08 ] Following bss_free() quirk introduced in commit 776b3580178f ("cfg80211: track hidden SSID networks properly"), adjust cfg80211_update_known_bss() to free the last beacon frame elements only if they're not shared via the corresponding 'hidden_beacon_bss' pointer. Reported-by: syzbot+30754ca335e6fb7e3092@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=30754ca335e6fb7e3092 Fixes: 3ab8227d3e7d ("cfg80211: refactor cfg80211_bss_update") Signed-off-by: Dmitry Antipov Link: https://patch.msgid.link/20250813135236.799384-1-dmantipov@yandex.ru Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/wireless/scan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 18398968b3ed7..33e6f41035506 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1219,7 +1219,8 @@ cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, */ f = rcu_access_pointer(new->pub.beacon_ies); - kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head); + if (!new->pub.hidden_beacon_bss) + kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head); return false; } -- 2.50.1