From 03db7716159477b595e9af01be8003b7e994cc79 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 10 Oct 2022 11:08:17 -1000 Subject: [PATCH] Revert "cgroup: enable cgroup_get_from_file() on cgroup1" This reverts commit f3a2aebdd6fb90e444d595e46de64e822af419da. The commit enabled looking up v1 cgroups via cgroup_get_from_file(). However, there are multiple users, including CLONE_INTO_CGROUP, which have been assuming that it would only look up v2 cgroups. Returning v1 cgroups breaks them. Let's revert the commit and retry later with a separate lookup interface which allows both v1 and v2. Signed-off-by: Tejun Heo Link: http://lkml.kernel.org/r/000000000000385cbf05ea3f1862@google.com Cc: Yosry Ahmed --- kernel/cgroup/cgroup.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index ecf409e3c3a7..6d8a5a40c24d 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -6234,6 +6234,11 @@ static struct cgroup *cgroup_get_from_file(struct file *f) return ERR_CAST(css); cgrp = css->cgroup; + if (!cgroup_on_dfl(cgrp)) { + cgroup_put(cgrp); + return ERR_PTR(-EBADF); + } + return cgrp; }