Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Revert "[PATCH] namespaces: fix exit race by splitting exit"
This reverts commit 7a238fcba0629b6f2edbcd37458bae56fcf36be5 in
preparation for a better and simpler fix proposed by Eric Biederman
(and fixed up by Serge Hallyn)
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+16
-40
+11
-19
include/linux/nsproxy.h
+11
-19
include/linux/nsproxy.h
···
35
35
int copy_namespaces(int flags, struct task_struct *tsk);
36
36
void get_task_namespaces(struct task_struct *tsk);
37
37
void free_nsproxy(struct nsproxy *ns);
38
-
struct nsproxy *put_nsproxy(struct nsproxy *ns);
39
38
40
-
static inline void finalize_put_nsproxy(struct nsproxy *ns)
39
+
static inline void put_nsproxy(struct nsproxy *ns)
41
40
{
42
-
if (ns)
41
+
if (atomic_dec_and_test(&ns->count)) {
43
42
free_nsproxy(ns);
43
+
}
44
44
}
45
45
46
-
static inline void put_and_finalize_nsproxy(struct nsproxy *ns)
46
+
static inline void exit_task_namespaces(struct task_struct *p)
47
47
{
48
-
finalize_put_nsproxy(put_nsproxy(ns));
49
-
}
50
-
51
-
static inline struct nsproxy *preexit_task_namespaces(struct task_struct *p)
52
-
{
53
-
return put_nsproxy(p->nsproxy);
54
-
}
55
-
56
-
static inline void exit_task_namespaces(struct task_struct *p,
57
-
struct nsproxy *ns)
58
-
{
59
-
task_lock(p);
60
-
p->nsproxy = NULL;
61
-
task_unlock(p);
62
-
finalize_put_nsproxy(ns);
48
+
struct nsproxy *ns = p->nsproxy;
49
+
if (ns) {
50
+
task_lock(p);
51
+
p->nsproxy = NULL;
52
+
task_unlock(p);
53
+
put_nsproxy(ns);
54
+
}
63
55
}
64
56
#endif
+2
-4
kernel/exit.c
+2
-4
kernel/exit.c
···
396
396
current->fs = fs;
397
397
atomic_inc(&fs->count);
398
398
399
-
put_and_finalize_nsproxy(current->nsproxy);
399
+
exit_task_namespaces(current);
400
400
current->nsproxy = init_task.nsproxy;
401
401
get_task_namespaces(current);
402
402
···
853
853
fastcall NORET_TYPE void do_exit(long code)
854
854
{
855
855
struct task_struct *tsk = current;
856
-
struct nsproxy *ns;
857
856
int group_dead;
858
857
859
858
profile_task_exit(tsk);
···
938
939
939
940
tsk->exit_code = code;
940
941
proc_exit_connector(tsk);
941
-
ns = preexit_task_namespaces(tsk);
942
942
exit_notify(tsk);
943
-
exit_task_namespaces(tsk, ns);
943
+
exit_task_namespaces(tsk);
944
944
#ifdef CONFIG_NUMA
945
945
mpol_free(tsk->mempolicy);
946
946
tsk->mempolicy = NULL;
+2
-2
kernel/fork.c
+2
-2
kernel/fork.c
···
1265
1265
return p;
1266
1266
1267
1267
bad_fork_cleanup_namespaces:
1268
-
put_and_finalize_nsproxy(p->nsproxy);
1268
+
exit_task_namespaces(p);
1269
1269
bad_fork_cleanup_keys:
1270
1270
exit_keys(p);
1271
1271
bad_fork_cleanup_mm:
···
1711
1711
}
1712
1712
1713
1713
if (new_nsproxy)
1714
-
put_and_finalize_nsproxy(new_nsproxy);
1714
+
put_nsproxy(new_nsproxy);
1715
1715
1716
1716
bad_unshare_cleanup_ipc:
1717
1717
if (new_ipc)
+1
-15
kernel/nsproxy.c
+1
-15
kernel/nsproxy.c
···
117
117
goto out_pid;
118
118
119
119
out:
120
-
put_and_finalize_nsproxy(old_ns);
120
+
put_nsproxy(old_ns);
121
121
return err;
122
122
123
123
out_pid:
···
133
133
tsk->nsproxy = old_ns;
134
134
kfree(new_ns);
135
135
goto out;
136
-
}
137
-
138
-
struct nsproxy *put_nsproxy(struct nsproxy *ns)
139
-
{
140
-
if (ns) {
141
-
if (atomic_dec_and_test(&ns->count)) {
142
-
if (ns->mnt_ns) {
143
-
put_mnt_ns(ns->mnt_ns);
144
-
ns->mnt_ns = NULL;
145
-
}
146
-
return ns;
147
-
}
148
-
}
149
-
return NULL;
150
136
}
151
137
152
138
void free_nsproxy(struct nsproxy *ns)