Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
ns: add asserts for initial namespace reference counts
They always remain fixed at one. Notice when that assumptions is broken.
Link: https://patch.msgid.link/20251110-work-namespace-nstree-fixes-v1-13-e8a9264e0fb9@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
+17
-9
+17
-9
include/linux/ns_common.h
+17
-9
include/linux/ns_common.h
···
60
60
return atomic_read(&ns->__ns_ref_active);
61
61
}
62
62
63
+
static __always_inline __must_check int __ns_ref_read(const struct ns_common *ns)
64
+
{
65
+
return refcount_read(&ns->__ns_ref);
66
+
}
67
+
63
68
static __always_inline __must_check bool __ns_ref_put(struct ns_common *ns)
64
69
{
65
-
if (is_ns_init_id(ns))
70
+
if (is_ns_init_id(ns)) {
71
+
VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1);
66
72
return false;
73
+
}
67
74
if (refcount_dec_and_test(&ns->__ns_ref)) {
68
75
VFS_WARN_ON_ONCE(__ns_ref_active_read(ns));
69
76
return true;
···
80
73
81
74
static __always_inline __must_check bool __ns_ref_get(struct ns_common *ns)
82
75
{
83
-
if (is_ns_init_id(ns))
76
+
if (is_ns_init_id(ns)) {
77
+
VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1);
84
78
return true;
79
+
}
85
80
if (refcount_inc_not_zero(&ns->__ns_ref))
86
81
return true;
87
82
VFS_WARN_ON_ONCE(__ns_ref_active_read(ns));
88
83
return false;
89
84
}
90
85
91
-
static __always_inline __must_check int __ns_ref_read(const struct ns_common *ns)
92
-
{
93
-
return refcount_read(&ns->__ns_ref);
94
-
}
95
-
96
86
static __always_inline void __ns_ref_inc(struct ns_common *ns)
97
87
{
98
-
if (is_ns_init_id(ns))
88
+
if (is_ns_init_id(ns)) {
89
+
VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1);
99
90
return;
91
+
}
100
92
refcount_inc(&ns->__ns_ref);
101
93
}
102
94
103
95
static __always_inline __must_check bool __ns_ref_dec_and_lock(struct ns_common *ns,
104
96
spinlock_t *ns_lock)
105
97
{
106
-
if (is_ns_init_id(ns))
98
+
if (is_ns_init_id(ns)) {
99
+
VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1);
107
100
return false;
101
+
}
108
102
return refcount_dec_and_lock(&ns->__ns_ref, ns_lock);
109
103
}
110
104