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Fri, 18 Jul 2025 04:54:26 -0700 (PDT) From: Zijiang Huang X-Google-Original-From: Zijiang Huang To: tj@kernel.org, hannes@cmpxchg.org, mkoutny@suse.com Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Zijiang Huang , Hao Peng Subject: [PATCH 2/2] cgroup: Fix reference count leak when cft->open is NULL Date: Fri, 18 Jul 2025 19:54:09 +0800 Message-ID: <20250718115409.878122-2-kerayhuang@tencent.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20250718115409.878122-1-kerayhuang@tencent.com> References: <20250718115409.878122-1-kerayhuang@tencent.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit When cft->open is NULL, it will cause ctx namespace reference count leak. Signed-off-by: Zijiang Huang Reviewed-by: Hao Peng --- kernel/cgroup/cgroup.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index a723b7dc6e4e..9bde0f4be687 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -4134,8 +4134,10 @@ static int cgroup_file_open(struct kernfs_open_file *of) get_cgroup_ns(ctx->ns); of->priv = ctx; - if (!cft->open) + if (!cft->open) { + get_cgroup_ns(ctx->ns); return 0; + } ret = cft->open(of); if (ret) { -- 2.43.5