From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann Droneaud Subject: [PATCHv6 3/6] binfmt_misc: use get_unused_fd_flags(0) instead of get_unused_fd() Date: Tue, 11 Mar 2014 11:23:42 +0100 Message-ID: References: Cc: Yann Droneaud , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton To: Al Viro Return-path: In-Reply-To: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Macro get_unused_fd() is used to allocate a file descriptor with default flags. Those default flags (0) can be "unsafe": O_CLOEXEC must be used by default to not leak file descriptor across exec(). Instead of macro get_unused_fd(), function get_unused_fd_flags() (or anon_inode_getfd()) should be used with flags given by userspace. If not possible, flags should be set to O_CLOEXEC to provide userspace with a default safe behavor. In a further patch, get_unused_fd() will be removed so that new code start using get_unused_fd_flags() (or anon_inode_getfd()) with correct flags. This patch replaces calls to get_unused_fd() with equivalent call to get_unused_fd_flags(0) to preserve current behavor for existing code. The hard coded flag value (0) should be reviewed on a per-subsystem basis, and, if possible, set to O_CLOEXEC. Link: http://lkml.kernel.org/r/cover.1394532336.git.ydroneaud@opteya.com Cc: Al Viro Cc: Andrew Morton Signed-off-by: Yann Droneaud --- fs/binfmt_misc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index 1c740e152f38..052f6dc8e549 100644 --- a/fs/binfmt_misc.c +++ b/fs/binfmt_misc.c @@ -138,7 +138,7 @@ static int load_misc_binary(struct linux_binprm *bprm) /* if the binary should be opened on behalf of the * interpreter than keep it open and assign descriptor * to it */ - fd_binary = get_unused_fd(); + fd_binary = get_unused_fd_flags(0); if (fd_binary < 0) { retval = fd_binary; goto _ret; -- 1.8.5.3