From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793212752; b=Eo4bsbFdo9RbtQThqsqBz1aLXmcTK683vaWS1WBDX8lxO3u73zejWAD7K4YNI/gYlBwC lUdZbO3gYX5uLtwfW508Vhe0gcKsBllRpR9T2hvKMJH6mCMCh9YVKJl6ZwwRNZKzmSU7x udortKNT4DlyzrHUDmzjfcwfNB4xSUKcwk1UtUx5SnJuy0zyfYgdQnYZQ0JHFJcVkAEcp D0YVSLGteIANOH0GJCemqYnvhPbJaoKUrPHBlfNQUwBdGuylldAhYRof95Kuu+RRPbkHk /fJVlS3r+Vq9+nJcdztINKom9MOMTS/aMBMr0z6IQjtP0x/omfgDUXsBfZH1mAHlpsA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793212752; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=b5VmDvhcrb9PLLsFD1JFwYkRxz32aDm58xJshcAAZwo=; b=e6yhn6F6cZsJYEHk6Iex7yj8NdZKlaGDCGDDxxuh0JzOn4ReMVnNCy7wW8WjwwU2/Ews NUlhOuQ+DYL6cHvuDPQhqCnIvIwh/wYs9pUg+FJ92MrlPn97xYxBKRgHEHfIF3gn0xibg I9NLJnD++RBSuMXOnqm0TM10HuCFPH8cMsPli2jpUyKYzb4hZ9ZR82Uy1EOTVRZwIiDVl Dl3D15HZG6Ks+l2UZ7lxYAtFUsAWSPf+AUbFYKK7RkUo8dpIqgb8BcpmhdmxDHuKUB0l/ mQX9oRctA/q5foO8V76rITJ4IEAEHFSJ6Rn52/WkcLHWibrnWTreVR+im3fLYiZ67Hg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=BJsnrrs8; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2AD7B606A31C; Wed, 28 Oct 2026 18:39:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=BJsnrrs8 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7980E1F01825; Wed, 28 Oct 2026 18:39:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793212752; bh=b5VmDvhcrb9PLLsFD1JFwYkRxz32aDm58xJshcAAZwo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BJsnrrs8Eo9DFpdSSAN7UlC3infBHaTX0pXeAGs0XmXE+gOjkQPJc6+TDKCOIcgv1 SED8vXEKXRo+XdMPcssyeKbG+mD54BzLLyyLo9XXeLeoySD71NPkmI8h3PagFx7ujZ n8UgqxEhIj7qzrNY6lY14H2B7ZNLRrSxnye7CNwA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhaofeng Chen , Yuxiao Wang , Alexander Graf Subject: [PATCH 6.1 0265/1887] nitro_enclaves: fix use-after-free on SLOT_ALLOC failure Date: Wed, 28 Oct 2026 17:39:21 +0100 Message-ID: <20261028170505.259581611@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yuxiao Wang commit 9bc184a2eda8b773c88ecbff934001ad649b9cc1 upstream. When ne_create_vm_ioctl() fails the SLOT_ALLOC request after anon_inode_getfile() has succeeded, the error path calls fput(enclave_file) and then frees ne_enclave. In normal userspace context, fput() defers the final __fput() via task_work. ne_enclave_release() therefore runs after ne_enclave has already been freed and dereferences ne_enclave->slot_uid, causing a use-after-free: KASAN: slab-use-after-free in ne_enclave_release. The enclave has no slot allocated and is not yet linked into the enclaves list on this error path, so ne_enclave_release() is expected to return early when slot_uid is zero. However, reading slot_uid already accesses the freed object. Clear enclave_file->private_data before fput() on the error path. ne_enclave_release() then returns immediately when private_data is NULL, leaving the ioctl error path as the sole owner of ne_enclave. This is safe because the file has not been fd_install()'d yet. Tested on an AWS EC2 m5.2xlarge with CONFIG_KASAN=y. Without the patch, the reproducer triggers a KASAN slab-use-after-free on every SLOT_ALLOC failure. With the patch, no KASAN report is produced and the SLOT_ALLOC error is still returned. Normal enclave creation and teardown are unaffected. Fixes: 9c8eb50fe9e2 ("nitro_enclaves: Add logic for terminating an enclave") Cc: stable@vger.kernel.org Co-developed-by: Zhaofeng Chen Signed-off-by: Zhaofeng Chen Signed-off-by: Yuxiao Wang Reviewed-by: Alexander Graf Link: https://patch.msgid.link/20260909124400.27857-1-graf@amazon.com Signed-off-by: Greg Kroah-Hartman --- drivers/virt/nitro_enclaves/ne_misc_dev.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/virt/nitro_enclaves/ne_misc_dev.c +++ b/drivers/virt/nitro_enclaves/ne_misc_dev.c @@ -1710,6 +1710,7 @@ static int ne_create_vm_ioctl(struct ne_ return enclave_fd; put_file: + enclave_file->private_data = NULL; fput(enclave_file); put_fd: put_unused_fd(enclave_fd);