From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7A4163BB112; Fri, 9 Oct 2026 14:36:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791556562; cv=none; b=p6ximgCy1bpk4jjaiyjzQ9wO2cEwaxO0FJuCB4cdQIlRxfP15GkHcp3c7Jd2RXCjeipwIi6C0/0hosp8zIkNfbAIL+fqVdg187EuKdAte9jzCsJa29zlgMJVMTYDj6/ESMMfNzTqvxhEnOolUQEljeaPYtO9qM78vnwJnAyQRr4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791556562; c=relaxed/simple; bh=NO+xwYp/o9f5WoGghD0Q/Kgn2NfKf/4WSBijfwD02UE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=vGV9UySuxCD24NlQQOXdwiFyXAQhnADddVdaN7UQvdfIQUU8oFRDKBnO6j8/FzSpMiQbADig2IE8MJzYfm8RW0wQkYH0tRCeyjsgphnlYOlt39PM5CDc7vttVkitgh9qreYXI789knckRzVDajFFwJuP0ejB9MTIzdzGt/qN5Cs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=D7g4Y6G7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="D7g4Y6G7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8DF31F000FF; Fri, 9 Oct 2026 14:36:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791556561; bh=z9En2woco1p9ByGwMW5Fg2mt7wGLDirjG5IpodcMTTs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=D7g4Y6G7W8Msy4QB92PJztLG2I5umElnlc0RDZ1BHBQO8uPk5FAhXfWRE4aux/tGz mTUi4JUT6APmRwIG9gS20BbmnKo0IaUNYZc7r7CJzkTLLXQI/1j/yuqiP53jt5V2OM xpNi4cMdNb/KEeA8SPYR4ceo+yIlBMir7O7JXizk= 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 7.2 201/428] nitro_enclaves: fix use-after-free on SLOT_ALLOC failure Date: Fri, 9 Oct 2026 16:08:58 +0200 Message-ID: <20261009140950.548891387@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261009140946.008206689@linuxfoundation.org> References: <20261009140946.008206689@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 7.2-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 @@ -1706,6 +1706,7 @@ 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);