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 5EB04C2D0; Mon, 11 Dec 2023 18:31:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="VOBY97VT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA8E8C433C7; Mon, 11 Dec 2023 18:31:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1702319519; bh=N2phUe92eyWjvfJ73Unsr3GzYc2LHsgMOgy3VHYYp/U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VOBY97VTuTGqXS+XpX1fzM3qVnR0zXmBDmBm1W9JtbEi35rzDTH/0tfZRYv+rugp5 5vqw5/otlIhfFJSiH/RXfm82zwCRK6H0Tg4Xj/4aFnq1f48yI1LHZ8Qw9VrY/dsNL+ +4LX6QwrZ1VhgqUS7kz65vzYBI0jtH62I+8S9SyM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Pavel Begunkov , Jens Axboe , Jann Horn Subject: [PATCH 6.6 134/244] io_uring/af_unix: disable sending io_uring over sockets Date: Mon, 11 Dec 2023 19:20:27 +0100 Message-ID: <20231211182051.807348021@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231211182045.784881756@linuxfoundation.org> References: <20231211182045.784881756@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pavel Begunkov commit 705318a99a138c29a512a72c3e0043b3cd7f55f4 upstream. File reference cycles have caused lots of problems for io_uring in the past, and it still doesn't work exactly right and races with unix_stream_read_generic(). The safest fix would be to completely disallow sending io_uring files via sockets via SCM_RIGHT, so there are no possible cycles invloving registered files and thus rendering SCM accounting on the io_uring side unnecessary. Cc: Fixes: 0091bfc81741b ("io_uring/af_unix: defer registered files gc to io_uring release") Reported-and-suggested-by: Jann Horn Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/c716c88321939156909cfa1bd8b0faaf1c804103.1701868795.git.asml.silence@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- io_uring/rsrc.h | 7 ------- net/core/scm.c | 6 ++++++ 2 files changed, 6 insertions(+), 7 deletions(-) --- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -77,17 +77,10 @@ int io_sqe_files_register(struct io_ring int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file); -#if defined(CONFIG_UNIX) -static inline bool io_file_need_scm(struct file *filp) -{ - return !!unix_get_socket(filp); -} -#else static inline bool io_file_need_scm(struct file *filp) { return false; } -#endif static inline int io_scm_file_account(struct io_ring_ctx *ctx, struct file *file) --- a/net/core/scm.c +++ b/net/core/scm.c @@ -26,6 +26,7 @@ #include #include #include +#include #include @@ -103,6 +104,11 @@ static int scm_fp_copy(struct cmsghdr *c if (fd < 0 || !(file = fget_raw(fd))) return -EBADF; + /* don't allow io_uring files */ + if (io_uring_get_socket(file)) { + fput(file); + return -EINVAL; + } *fpp++ = file; fpl->count++; }