5.15-stable review patch. If anyone has any objections, please let me know.
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From: Christian Brauner brauner@kernel.org
commit ca7707f5430ad6b1c9cb7cee0a7f67d69328bb2d upstream.
Stop open-coding get_unused_fd_flags() and anon_inode_getfile(). That's brittle just for keeping the flags between both calls in sync. Use the dedicated helper.
Message-Id: 20230327-pidfd-file-api-v1-2-5c0e9a3158e4@kernel.org Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/fork.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-)
--- a/kernel/fork.c +++ b/kernel/fork.c @@ -2317,21 +2317,12 @@ static __latent_entropy struct task_stru * if the fd table isn't shared). */ if (clone_flags & CLONE_PIDFD) { - retval = get_unused_fd_flags(O_RDWR | O_CLOEXEC); + /* Note that no task has been attached to @pid yet. */ + retval = __pidfd_prepare(pid, O_RDWR | O_CLOEXEC, &pidfile); if (retval < 0) goto bad_fork_free_pid; - pidfd = retval;
- pidfile = anon_inode_getfile("[pidfd]", &pidfd_fops, pid, - O_RDWR | O_CLOEXEC); - if (IS_ERR(pidfile)) { - put_unused_fd(pidfd); - retval = PTR_ERR(pidfile); - goto bad_fork_free_pid; - } - get_pid(pid); /* held by pidfile now */ - retval = put_user(pidfd, args->pidfd); if (retval) goto bad_fork_put_pidfd;