From: Sargun Dhillon <sargun@sargun.me>
To: Kees Cook <keescook@chromium.org>, linux-kernel@vger.kernel.org
Cc: Sargun Dhillon <sargun@sargun.me>,
Tycho Andersen <tycho@tycho.ws>,
Matt Denton <mpdenton@google.com>, Jann Horn <jannh@google.com>,
Chris Palmer <palmer@google.com>,
Aleksa Sarai <cyphar@cyphar.com>,
Robert Sesek <rsesek@google.com>,
Christian Brauner <christian.brauner@ubuntu.com>,
containers@lists.linux-foundation.org,
Giuseppe Scrivano <gscrivan@redhat.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Al Viro <viro@zeniv.linux.org.uk>,
Daniel Wagner <daniel.wagner@bmw-carit.de>,
"David S . Miller" <davem@davemloft.net>,
John Fastabend <john.r.fastabend@intel.com>,
Tejun Heo <tj@kernel.org>,
stable@vger.kernel.org, cgroups@vger.kernel.org,
linux-fsdevel@vger.kernel.org
Subject: [PATCH v3 2/4] pid: Use file_receive helper to copy FDs
Date: Tue, 2 Jun 2020 18:10:42 -0700 [thread overview]
Message-ID: <20200603011044.7972-3-sargun@sargun.me> (raw)
In-Reply-To: <20200603011044.7972-1-sargun@sargun.me>
The code to copy file descriptors was duplicated in pidfd_getfd.
Rather than continue to duplicate it, this hoists the code out of
kernel/pid.c and uses the newly added file_receive helper.
Earlier, when this was implemented there was some back-and-forth
about how the semantics should work around copying around file
descriptors [1], and it was decided that the default behaviour
should be to not modify cgroup data. As a matter of least surprise,
this approach follows the default semantics as presented by SCM_RIGHTS.
In the future, a flag can be added to avoid manipulating the cgroup
data on copy.
[1]: https://lore.kernel.org/lkml/20200107175927.4558-1-sargun@sargun.me/
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Suggested-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Daniel Wagner <daniel.wagner@bmw-carit.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jann Horn <jannh@google.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: stable@vger.kernel.org
Cc: cgroups@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
kernel/pid.c | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)
diff --git a/kernel/pid.c b/kernel/pid.c
index c835b844aca7..1642cf940aa1 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -606,7 +606,7 @@ static int pidfd_getfd(struct pid *pid, int fd)
{
struct task_struct *task;
struct file *file;
- int ret;
+ int ret, err;
task = get_pid_task(pid, PIDTYPE_PID);
if (!task)
@@ -617,18 +617,16 @@ static int pidfd_getfd(struct pid *pid, int fd)
if (IS_ERR(file))
return PTR_ERR(file);
- ret = security_file_receive(file);
- if (ret) {
- fput(file);
- return ret;
- }
-
ret = get_unused_fd_flags(O_CLOEXEC);
- if (ret < 0)
- fput(file);
- else
- fd_install(ret, file);
+ if (ret >= 0) {
+ err = file_receive(ret, file);
+ if (err) {
+ put_unused_fd(ret);
+ ret = err;
+ }
+ }
+ fput(file);
return ret;
}
--
2.25.1
next prev parent reply other threads:[~2020-06-03 1:14 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20200603011044.7972-1-sargun@sargun.me>
2020-06-03 1:10 ` [PATCH v3 1/4] fs, net: Standardize on file_receive helper to move fds across processes Sargun Dhillon
2020-06-04 1:24 ` Christian Brauner
2020-06-04 2:22 ` Kees Cook
2020-06-04 5:20 ` Sargun Dhillon
2020-06-04 12:52 ` Christian Brauner
2020-06-04 13:28 ` David Laight
2020-06-05 7:54 ` Sargun Dhillon
2020-06-09 19:43 ` Kees Cook
2020-06-09 20:03 ` Christian Brauner
2020-06-09 20:55 ` Kees Cook
2020-06-09 21:27 ` Christian Brauner
2020-06-10 5:27 ` Kees Cook
2020-06-10 8:12 ` Sargun Dhillon
2020-06-10 8:48 ` David Laight
2020-06-11 3:02 ` Kees Cook
2020-06-11 7:51 ` David Laight
2020-06-10 17:10 ` Kees Cook
2020-06-11 2:59 ` Kees Cook
2020-06-11 4:41 ` Sargun Dhillon
2020-06-11 9:19 ` Christian Brauner
2020-06-11 10:39 ` Sargun Dhillon
2020-06-11 23:23 ` Kees Cook
2020-06-11 10:01 ` Christian Brauner
2020-06-11 11:06 ` Sargun Dhillon
2020-06-11 14:42 ` Christian Brauner
2020-06-11 14:56 ` David Laight
2020-06-11 23:49 ` Kees Cook
2020-06-12 6:58 ` Kees Cook
2020-06-12 8:36 ` David Laight
2020-06-12 10:46 ` Sargun Dhillon
2020-06-12 15:13 ` Kees Cook
2020-06-12 15:55 ` David Laight
2020-06-12 18:28 ` Christian Brauner
2020-06-12 18:38 ` Kees Cook
2020-06-12 18:42 ` Christian Brauner
2020-06-15 8:27 ` David Laight
2020-06-10 9:30 ` Christian Brauner
2020-06-04 3:39 ` Sargun Dhillon
2020-06-03 1:10 ` Sargun Dhillon [this message]
2020-06-03 1:10 ` [PATCH v3 3/4] seccomp: Introduce addfd ioctl to seccomp user notifier Sargun Dhillon
2020-06-03 1:10 ` [PATCH v3 4/4] selftests/seccomp: Test SECCOMP_IOCTL_NOTIF_ADDFD Sargun Dhillon
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