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=1793210925; b=ZD/ykb2uY8jr2wxV2mQ1qnePOV+Ppq5njabqzzr66/YIuqRY8B1E/DvowdHh2A9cTXlr 3t9jXue4xU2Zhpem5GTPPd7e905SOh2sLV05HJ9uA+bmFIFi34bVYq+2ziKVvYxgZ+ju3 6xiEr34O4Sv+ih3XabI6G9gin0OHLbDVTuncgQALIMiMNe9wK3vSN2YP6YWfm/FWJQMar yrXO3D9pqDRtXIdlheBO9dUqj1bF1CFQdl4UW+PMFr3NgUVn+Rx4ndErNUR7SAWsNmwNj fq3Nm7ESIYX/eVyqevsCFAiXdJAqlZj0Bc7IRMa//h3W4C0pAgf0Js95XjP/Cvfjrow== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793210925; 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=7FLcdwmYNWfjD7i+KtjIAwfbfnSNONTnLUjGYTwF/Bc=; b=A1PpGzKVt62VtUP+8CYgMFeyWVJOoyyU6n6/f9obw8RKbzhOeHV8+D31AXOxgWw7aI8h I8hBWEXq8Vmjm0mbRC5PJHZdmjzlEQ6zKFm4jmgVTnw2nE+I6fMFh9LD4pcfxmdrJJCIm St29NmEGKNfMBYyqqWcm++4JPNYXquQWMCnKDlzqSp9ztvuZ+GG5r2SgohGfyw8W9vVpQ GlLO2niZXuTUly+iwx/4IO5fup9dv3tGYb+swTmw6wvx0j5YOOn8xo+F14cW4QaIVXkQw 8reYy1P2+0QVhWYA5zs8m/oYY6327BSAx8im5uoZ6DKD7E+pifsDr8WMis5A53kTq+g== 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=WmIPAEUH; 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 DD006606A31E; Wed, 28 Oct 2026 18:08:44 +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=WmIPAEUH Received: by smtp.kernel.org (Postfix) with ESMTPSA id 371D11F01825; Wed, 28 Oct 2026 18:08:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793210924; bh=7FLcdwmYNWfjD7i+KtjIAwfbfnSNONTnLUjGYTwF/Bc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WmIPAEUHBT6yfIWqnjbltqjP+AU951kIapyNPibeD5i+KViucbkUIUAJ3KmcfCLRf dsow/stn51jwcC0apMtlyCHDHaxF+oaJHOW1wStY5Ifuv614aw0q1scMKFdAVHkGK8 609C6cfWlaMxPRBMZUq1e25FS6p2oOpWgxZf284s= 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 5.15 197/571] nitro_enclaves: fix use-after-free on SLOT_ALLOC failure Date: Wed, 28 Oct 2026 17:55:44 +0100 Message-ID: <20261028170012.682187121@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170008.009143722@linuxfoundation.org> References: <20261028170008.009143722@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 5.15-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 @@ -1654,6 +1654,7 @@ 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);