mirror of https://gitee.com/openkylin/linux.git
Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl
Pull sysctl updates from Eric Biederman: - Rewrite of sysctl for speed and clarity. Insert/remove/Lookup in sysctl are all now O(NlogN) operations, and are no longer bottlenecks in the process of adding and removing network devices. sysctl is now focused on being a filesystem instead of system call and the code can all be found in fs/proc/proc_sysctl.c. Hopefully this means the code is now approachable. Much thanks is owed to Lucian Grinjincu for keeping at this until something was found that was usable. - The recent proc_sys_poll oops found by the fuzzer during hibernation is fixed. * git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl: (36 commits) sysctl: protect poll() in entries that may go away sysctl: Don't call sysctl_follow_link unless we are a link. sysctl: Comments to make the code clearer. sysctl: Correct error return from get_subdir sysctl: An easier to read version of find_subdir sysctl: fix memset parameters in setup_sysctl_set() sysctl: remove an unused variable sysctl: Add register_sysctl for normal sysctl users sysctl: Index sysctl directories with rbtrees. sysctl: Make the header lists per directory. sysctl: Move sysctl_check_dups into insert_header sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy sysctl: Replace root_list with links between sysctl_table_sets. sysctl: Add sysctl_print_dir and use it in get_subdir sysctl: Stop requiring explicit management of sysctl directories sysctl: Add a root pointer to ctl_table_set sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry. sysctl: Normalize the root_table data structure. sysctl: Factor out insert_header and erase_header ...
This commit is contained in:
commit
f1d38e423a
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@ -10,12 +10,15 @@
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*/
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#include <linux/proc_fs.h>
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struct ctl_table_header;
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extern struct proc_dir_entry proc_root;
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#ifdef CONFIG_PROC_SYSCTL
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extern int proc_sys_init(void);
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extern void sysctl_head_put(struct ctl_table_header *head);
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#else
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static inline void proc_sys_init(void) { }
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static inline void sysctl_head_put(struct ctl_table_header *head) { }
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#endif
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#ifdef CONFIG_NET
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extern int proc_net_init(void);
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|
|
File diff suppressed because it is too large
Load Diff
|
@ -932,34 +932,14 @@ enum
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#include <linux/list.h>
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#include <linux/rcupdate.h>
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#include <linux/wait.h>
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#include <linux/rbtree.h>
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/* For the /proc/sys support */
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struct ctl_table;
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struct nsproxy;
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struct ctl_table_root;
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struct ctl_table_set {
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struct list_head list;
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struct ctl_table_set *parent;
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int (*is_seen)(struct ctl_table_set *);
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};
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extern void setup_sysctl_set(struct ctl_table_set *p,
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struct ctl_table_set *parent,
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int (*is_seen)(struct ctl_table_set *));
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struct ctl_table_header;
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extern void sysctl_head_get(struct ctl_table_header *);
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extern void sysctl_head_put(struct ctl_table_header *);
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extern int sysctl_is_seen(struct ctl_table_header *);
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extern struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *);
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extern struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev);
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extern struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
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struct ctl_table_header *prev);
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extern void sysctl_head_finish(struct ctl_table_header *prev);
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extern int sysctl_perm(struct ctl_table_root *root,
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struct ctl_table *table, int op);
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struct ctl_dir;
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typedef struct ctl_table ctl_table;
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@ -1023,8 +1003,6 @@ static inline void *proc_sys_poll_event(struct ctl_table_poll *poll)
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return (void *)(unsigned long)atomic_read(&poll->event);
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}
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void proc_sys_poll_notify(struct ctl_table_poll *poll);
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#define __CTL_TABLE_POLL_INITIALIZER(name) { \
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.event = ATOMIC_INIT(0), \
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.wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.wait) }
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|
@ -1039,21 +1017,16 @@ struct ctl_table
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void *data;
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int maxlen;
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umode_t mode;
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struct ctl_table *child;
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struct ctl_table *parent; /* Automatically set */
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struct ctl_table *child; /* Deprecated */
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proc_handler *proc_handler; /* Callback for text formatting */
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struct ctl_table_poll *poll;
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void *extra1;
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void *extra2;
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};
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struct ctl_table_root {
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struct list_head root_list;
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struct ctl_table_set default_set;
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struct ctl_table_set *(*lookup)(struct ctl_table_root *root,
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struct nsproxy *namespaces);
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int (*permissions)(struct ctl_table_root *root,
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struct nsproxy *namespaces, struct ctl_table *table);
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struct ctl_node {
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struct rb_node node;
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struct ctl_table_header *header;
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};
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/* struct ctl_table_header is used to maintain dynamic lists of
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|
@ -1063,9 +1036,9 @@ struct ctl_table_header
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union {
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struct {
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||||
struct ctl_table *ctl_table;
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||||
struct list_head ctl_entry;
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int used;
|
||||
int count;
|
||||
int nreg;
|
||||
};
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struct rcu_head rcu;
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||||
};
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|
@ -1073,9 +1046,27 @@ struct ctl_table_header
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struct ctl_table *ctl_table_arg;
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struct ctl_table_root *root;
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struct ctl_table_set *set;
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struct ctl_table *attached_by;
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struct ctl_table *attached_to;
|
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struct ctl_table_header *parent;
|
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struct ctl_dir *parent;
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||||
struct ctl_node *node;
|
||||
};
|
||||
|
||||
struct ctl_dir {
|
||||
/* Header must be at the start of ctl_dir */
|
||||
struct ctl_table_header header;
|
||||
struct rb_root root;
|
||||
};
|
||||
|
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struct ctl_table_set {
|
||||
int (*is_seen)(struct ctl_table_set *);
|
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struct ctl_dir dir;
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};
|
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|
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struct ctl_table_root {
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struct ctl_table_set default_set;
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struct ctl_table_set *(*lookup)(struct ctl_table_root *root,
|
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struct nsproxy *namespaces);
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int (*permissions)(struct ctl_table_root *root,
|
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struct nsproxy *namespaces, struct ctl_table *table);
|
||||
};
|
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|
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/* struct ctl_path describes where in the hierarchy a table is added */
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|
@ -1083,16 +1074,53 @@ struct ctl_path {
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const char *procname;
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};
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#ifdef CONFIG_SYSCTL
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void proc_sys_poll_notify(struct ctl_table_poll *poll);
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||||
|
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extern void setup_sysctl_set(struct ctl_table_set *p,
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struct ctl_table_root *root,
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int (*is_seen)(struct ctl_table_set *));
|
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extern void retire_sysctl_set(struct ctl_table_set *set);
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|
||||
void register_sysctl_root(struct ctl_table_root *root);
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struct ctl_table_header *__register_sysctl_table(
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struct ctl_table_set *set,
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const char *path, struct ctl_table *table);
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struct ctl_table_header *__register_sysctl_paths(
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struct ctl_table_root *root, struct nsproxy *namespaces,
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struct ctl_table_set *set,
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const struct ctl_path *path, struct ctl_table *table);
|
||||
struct ctl_table_header *register_sysctl(const char *path, struct ctl_table *table);
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||||
struct ctl_table_header *register_sysctl_table(struct ctl_table * table);
|
||||
struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
|
||||
struct ctl_table *table);
|
||||
|
||||
void unregister_sysctl_table(struct ctl_table_header * table);
|
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int sysctl_check_table(struct nsproxy *namespaces, struct ctl_table *table);
|
||||
|
||||
extern int sysctl_init(void);
|
||||
#else /* CONFIG_SYSCTL */
|
||||
static inline struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
|
||||
{
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static inline struct ctl_table_header *register_sysctl_paths(
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const struct ctl_path *path, struct ctl_table *table)
|
||||
{
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return NULL;
|
||||
}
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||||
|
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static inline void unregister_sysctl_table(struct ctl_table_header * table)
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{
|
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}
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|
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static inline void setup_sysctl_set(struct ctl_table_set *p,
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struct ctl_table_root *root,
|
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int (*is_seen)(struct ctl_table_set *))
|
||||
{
|
||||
}
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||||
|
||||
#endif /* CONFIG_SYSCTL */
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|
||||
#endif /* __KERNEL__ */
|
||||
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||||
|
|
|
@ -27,7 +27,6 @@ obj-y += power/
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|
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obj-$(CONFIG_FREEZER) += freezer.o
|
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obj-$(CONFIG_PROFILING) += profile.o
|
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obj-$(CONFIG_SYSCTL_SYSCALL_CHECK) += sysctl_check.o
|
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obj-$(CONFIG_STACKTRACE) += stacktrace.o
|
||||
obj-y += time/
|
||||
obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
|
||||
|
|
501
kernel/sysctl.c
501
kernel/sysctl.c
|
@ -193,20 +193,6 @@ static int sysrq_sysctl_handler(ctl_table *table, int write,
|
|||
|
||||
#endif
|
||||
|
||||
static struct ctl_table root_table[];
|
||||
static struct ctl_table_root sysctl_table_root;
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||||
static struct ctl_table_header root_table_header = {
|
||||
{{.count = 1,
|
||||
.ctl_table = root_table,
|
||||
.ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}},
|
||||
.root = &sysctl_table_root,
|
||||
.set = &sysctl_table_root.default_set,
|
||||
};
|
||||
static struct ctl_table_root sysctl_table_root = {
|
||||
.root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
|
||||
.default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
|
||||
};
|
||||
|
||||
static struct ctl_table kern_table[];
|
||||
static struct ctl_table vm_table[];
|
||||
static struct ctl_table fs_table[];
|
||||
|
@ -223,7 +209,7 @@ int sysctl_legacy_va_layout;
|
|||
|
||||
/* The default sysctl tables: */
|
||||
|
||||
static struct ctl_table root_table[] = {
|
||||
static struct ctl_table sysctl_base_table[] = {
|
||||
{
|
||||
.procname = "kernel",
|
||||
.mode = 0555,
|
||||
|
@ -1560,490 +1546,12 @@ static struct ctl_table dev_table[] = {
|
|||
{ }
|
||||
};
|
||||
|
||||
static DEFINE_SPINLOCK(sysctl_lock);
|
||||
|
||||
/* called under sysctl_lock */
|
||||
static int use_table(struct ctl_table_header *p)
|
||||
int __init sysctl_init(void)
|
||||
{
|
||||
if (unlikely(p->unregistering))
|
||||
return 0;
|
||||
p->used++;
|
||||
return 1;
|
||||
}
|
||||
|
||||
/* called under sysctl_lock */
|
||||
static void unuse_table(struct ctl_table_header *p)
|
||||
{
|
||||
if (!--p->used)
|
||||
if (unlikely(p->unregistering))
|
||||
complete(p->unregistering);
|
||||
}
|
||||
|
||||
/* called under sysctl_lock, will reacquire if has to wait */
|
||||
static void start_unregistering(struct ctl_table_header *p)
|
||||
{
|
||||
/*
|
||||
* if p->used is 0, nobody will ever touch that entry again;
|
||||
* we'll eliminate all paths to it before dropping sysctl_lock
|
||||
*/
|
||||
if (unlikely(p->used)) {
|
||||
struct completion wait;
|
||||
init_completion(&wait);
|
||||
p->unregistering = &wait;
|
||||
spin_unlock(&sysctl_lock);
|
||||
wait_for_completion(&wait);
|
||||
spin_lock(&sysctl_lock);
|
||||
} else {
|
||||
/* anything non-NULL; we'll never dereference it */
|
||||
p->unregistering = ERR_PTR(-EINVAL);
|
||||
}
|
||||
/*
|
||||
* do not remove from the list until nobody holds it; walking the
|
||||
* list in do_sysctl() relies on that.
|
||||
*/
|
||||
list_del_init(&p->ctl_entry);
|
||||
}
|
||||
|
||||
void sysctl_head_get(struct ctl_table_header *head)
|
||||
{
|
||||
spin_lock(&sysctl_lock);
|
||||
head->count++;
|
||||
spin_unlock(&sysctl_lock);
|
||||
}
|
||||
|
||||
void sysctl_head_put(struct ctl_table_header *head)
|
||||
{
|
||||
spin_lock(&sysctl_lock);
|
||||
if (!--head->count)
|
||||
kfree_rcu(head, rcu);
|
||||
spin_unlock(&sysctl_lock);
|
||||
}
|
||||
|
||||
struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
|
||||
{
|
||||
if (!head)
|
||||
BUG();
|
||||
spin_lock(&sysctl_lock);
|
||||
if (!use_table(head))
|
||||
head = ERR_PTR(-ENOENT);
|
||||
spin_unlock(&sysctl_lock);
|
||||
return head;
|
||||
}
|
||||
|
||||
void sysctl_head_finish(struct ctl_table_header *head)
|
||||
{
|
||||
if (!head)
|
||||
return;
|
||||
spin_lock(&sysctl_lock);
|
||||
unuse_table(head);
|
||||
spin_unlock(&sysctl_lock);
|
||||
}
|
||||
|
||||
static struct ctl_table_set *
|
||||
lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
|
||||
{
|
||||
struct ctl_table_set *set = &root->default_set;
|
||||
if (root->lookup)
|
||||
set = root->lookup(root, namespaces);
|
||||
return set;
|
||||
}
|
||||
|
||||
static struct list_head *
|
||||
lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
|
||||
{
|
||||
struct ctl_table_set *set = lookup_header_set(root, namespaces);
|
||||
return &set->list;
|
||||
}
|
||||
|
||||
struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
|
||||
struct ctl_table_header *prev)
|
||||
{
|
||||
struct ctl_table_root *root;
|
||||
struct list_head *header_list;
|
||||
struct ctl_table_header *head;
|
||||
struct list_head *tmp;
|
||||
|
||||
spin_lock(&sysctl_lock);
|
||||
if (prev) {
|
||||
head = prev;
|
||||
tmp = &prev->ctl_entry;
|
||||
unuse_table(prev);
|
||||
goto next;
|
||||
}
|
||||
tmp = &root_table_header.ctl_entry;
|
||||
for (;;) {
|
||||
head = list_entry(tmp, struct ctl_table_header, ctl_entry);
|
||||
|
||||
if (!use_table(head))
|
||||
goto next;
|
||||
spin_unlock(&sysctl_lock);
|
||||
return head;
|
||||
next:
|
||||
root = head->root;
|
||||
tmp = tmp->next;
|
||||
header_list = lookup_header_list(root, namespaces);
|
||||
if (tmp != header_list)
|
||||
continue;
|
||||
|
||||
do {
|
||||
root = list_entry(root->root_list.next,
|
||||
struct ctl_table_root, root_list);
|
||||
if (root == &sysctl_table_root)
|
||||
goto out;
|
||||
header_list = lookup_header_list(root, namespaces);
|
||||
} while (list_empty(header_list));
|
||||
tmp = header_list->next;
|
||||
}
|
||||
out:
|
||||
spin_unlock(&sysctl_lock);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
|
||||
{
|
||||
return __sysctl_head_next(current->nsproxy, prev);
|
||||
}
|
||||
|
||||
void register_sysctl_root(struct ctl_table_root *root)
|
||||
{
|
||||
spin_lock(&sysctl_lock);
|
||||
list_add_tail(&root->root_list, &sysctl_table_root.root_list);
|
||||
spin_unlock(&sysctl_lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* sysctl_perm does NOT grant the superuser all rights automatically, because
|
||||
* some sysctl variables are readonly even to root.
|
||||
*/
|
||||
|
||||
static int test_perm(int mode, int op)
|
||||
{
|
||||
if (!current_euid())
|
||||
mode >>= 6;
|
||||
else if (in_egroup_p(0))
|
||||
mode >>= 3;
|
||||
if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
|
||||
return 0;
|
||||
return -EACCES;
|
||||
}
|
||||
|
||||
int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
|
||||
{
|
||||
int mode;
|
||||
|
||||
if (root->permissions)
|
||||
mode = root->permissions(root, current->nsproxy, table);
|
||||
else
|
||||
mode = table->mode;
|
||||
|
||||
return test_perm(mode, op);
|
||||
}
|
||||
|
||||
static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
|
||||
{
|
||||
for (; table->procname; table++) {
|
||||
table->parent = parent;
|
||||
if (table->child)
|
||||
sysctl_set_parent(table, table->child);
|
||||
}
|
||||
}
|
||||
|
||||
static __init int sysctl_init(void)
|
||||
{
|
||||
sysctl_set_parent(NULL, root_table);
|
||||
#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
|
||||
sysctl_check_table(current->nsproxy, root_table);
|
||||
#endif
|
||||
register_sysctl_table(sysctl_base_table);
|
||||
return 0;
|
||||
}
|
||||
|
||||
core_initcall(sysctl_init);
|
||||
|
||||
static struct ctl_table *is_branch_in(struct ctl_table *branch,
|
||||
struct ctl_table *table)
|
||||
{
|
||||
struct ctl_table *p;
|
||||
const char *s = branch->procname;
|
||||
|
||||
/* branch should have named subdirectory as its first element */
|
||||
if (!s || !branch->child)
|
||||
return NULL;
|
||||
|
||||
/* ... and nothing else */
|
||||
if (branch[1].procname)
|
||||
return NULL;
|
||||
|
||||
/* table should contain subdirectory with the same name */
|
||||
for (p = table; p->procname; p++) {
|
||||
if (!p->child)
|
||||
continue;
|
||||
if (p->procname && strcmp(p->procname, s) == 0)
|
||||
return p;
|
||||
}
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* see if attaching q to p would be an improvement */
|
||||
static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
|
||||
{
|
||||
struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
|
||||
struct ctl_table *next;
|
||||
int is_better = 0;
|
||||
int not_in_parent = !p->attached_by;
|
||||
|
||||
while ((next = is_branch_in(by, to)) != NULL) {
|
||||
if (by == q->attached_by)
|
||||
is_better = 1;
|
||||
if (to == p->attached_by)
|
||||
not_in_parent = 1;
|
||||
by = by->child;
|
||||
to = next->child;
|
||||
}
|
||||
|
||||
if (is_better && not_in_parent) {
|
||||
q->attached_by = by;
|
||||
q->attached_to = to;
|
||||
q->parent = p;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* __register_sysctl_paths - register a sysctl hierarchy
|
||||
* @root: List of sysctl headers to register on
|
||||
* @namespaces: Data to compute which lists of sysctl entries are visible
|
||||
* @path: The path to the directory the sysctl table is in.
|
||||
* @table: the top-level table structure
|
||||
*
|
||||
* Register a sysctl table hierarchy. @table should be a filled in ctl_table
|
||||
* array. A completely 0 filled entry terminates the table.
|
||||
*
|
||||
* The members of the &struct ctl_table structure are used as follows:
|
||||
*
|
||||
* procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
|
||||
* enter a sysctl file
|
||||
*
|
||||
* data - a pointer to data for use by proc_handler
|
||||
*
|
||||
* maxlen - the maximum size in bytes of the data
|
||||
*
|
||||
* mode - the file permissions for the /proc/sys file, and for sysctl(2)
|
||||
*
|
||||
* child - a pointer to the child sysctl table if this entry is a directory, or
|
||||
* %NULL.
|
||||
*
|
||||
* proc_handler - the text handler routine (described below)
|
||||
*
|
||||
* de - for internal use by the sysctl routines
|
||||
*
|
||||
* extra1, extra2 - extra pointers usable by the proc handler routines
|
||||
*
|
||||
* Leaf nodes in the sysctl tree will be represented by a single file
|
||||
* under /proc; non-leaf nodes will be represented by directories.
|
||||
*
|
||||
* sysctl(2) can automatically manage read and write requests through
|
||||
* the sysctl table. The data and maxlen fields of the ctl_table
|
||||
* struct enable minimal validation of the values being written to be
|
||||
* performed, and the mode field allows minimal authentication.
|
||||
*
|
||||
* There must be a proc_handler routine for any terminal nodes
|
||||
* mirrored under /proc/sys (non-terminals are handled by a built-in
|
||||
* directory handler). Several default handlers are available to
|
||||
* cover common cases -
|
||||
*
|
||||
* proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
|
||||
* proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
|
||||
* proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
|
||||
*
|
||||
* It is the handler's job to read the input buffer from user memory
|
||||
* and process it. The handler should return 0 on success.
|
||||
*
|
||||
* This routine returns %NULL on a failure to register, and a pointer
|
||||
* to the table header on success.
|
||||
*/
|
||||
struct ctl_table_header *__register_sysctl_paths(
|
||||
struct ctl_table_root *root,
|
||||
struct nsproxy *namespaces,
|
||||
const struct ctl_path *path, struct ctl_table *table)
|
||||
{
|
||||
struct ctl_table_header *header;
|
||||
struct ctl_table *new, **prevp;
|
||||
unsigned int n, npath;
|
||||
struct ctl_table_set *set;
|
||||
|
||||
/* Count the path components */
|
||||
for (npath = 0; path[npath].procname; ++npath)
|
||||
;
|
||||
|
||||
/*
|
||||
* For each path component, allocate a 2-element ctl_table array.
|
||||
* The first array element will be filled with the sysctl entry
|
||||
* for this, the second will be the sentinel (procname == 0).
|
||||
*
|
||||
* We allocate everything in one go so that we don't have to
|
||||
* worry about freeing additional memory in unregister_sysctl_table.
|
||||
*/
|
||||
header = kzalloc(sizeof(struct ctl_table_header) +
|
||||
(2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
|
||||
if (!header)
|
||||
return NULL;
|
||||
|
||||
new = (struct ctl_table *) (header + 1);
|
||||
|
||||
/* Now connect the dots */
|
||||
prevp = &header->ctl_table;
|
||||
for (n = 0; n < npath; ++n, ++path) {
|
||||
/* Copy the procname */
|
||||
new->procname = path->procname;
|
||||
new->mode = 0555;
|
||||
|
||||
*prevp = new;
|
||||
prevp = &new->child;
|
||||
|
||||
new += 2;
|
||||
}
|
||||
*prevp = table;
|
||||
header->ctl_table_arg = table;
|
||||
|
||||
INIT_LIST_HEAD(&header->ctl_entry);
|
||||
header->used = 0;
|
||||
header->unregistering = NULL;
|
||||
header->root = root;
|
||||
sysctl_set_parent(NULL, header->ctl_table);
|
||||
header->count = 1;
|
||||
#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
|
||||
if (sysctl_check_table(namespaces, header->ctl_table)) {
|
||||
kfree(header);
|
||||
return NULL;
|
||||
}
|
||||
#endif
|
||||
spin_lock(&sysctl_lock);
|
||||
header->set = lookup_header_set(root, namespaces);
|
||||
header->attached_by = header->ctl_table;
|
||||
header->attached_to = root_table;
|
||||
header->parent = &root_table_header;
|
||||
for (set = header->set; set; set = set->parent) {
|
||||
struct ctl_table_header *p;
|
||||
list_for_each_entry(p, &set->list, ctl_entry) {
|
||||
if (p->unregistering)
|
||||
continue;
|
||||
try_attach(p, header);
|
||||
}
|
||||
}
|
||||
header->parent->count++;
|
||||
list_add_tail(&header->ctl_entry, &header->set->list);
|
||||
spin_unlock(&sysctl_lock);
|
||||
|
||||
return header;
|
||||
}
|
||||
|
||||
/**
|
||||
* register_sysctl_table_path - register a sysctl table hierarchy
|
||||
* @path: The path to the directory the sysctl table is in.
|
||||
* @table: the top-level table structure
|
||||
*
|
||||
* Register a sysctl table hierarchy. @table should be a filled in ctl_table
|
||||
* array. A completely 0 filled entry terminates the table.
|
||||
*
|
||||
* See __register_sysctl_paths for more details.
|
||||
*/
|
||||
struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
|
||||
struct ctl_table *table)
|
||||
{
|
||||
return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
|
||||
path, table);
|
||||
}
|
||||
|
||||
/**
|
||||
* register_sysctl_table - register a sysctl table hierarchy
|
||||
* @table: the top-level table structure
|
||||
*
|
||||
* Register a sysctl table hierarchy. @table should be a filled in ctl_table
|
||||
* array. A completely 0 filled entry terminates the table.
|
||||
*
|
||||
* See register_sysctl_paths for more details.
|
||||
*/
|
||||
struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
|
||||
{
|
||||
static const struct ctl_path null_path[] = { {} };
|
||||
|
||||
return register_sysctl_paths(null_path, table);
|
||||
}
|
||||
|
||||
/**
|
||||
* unregister_sysctl_table - unregister a sysctl table hierarchy
|
||||
* @header: the header returned from register_sysctl_table
|
||||
*
|
||||
* Unregisters the sysctl table and all children. proc entries may not
|
||||
* actually be removed until they are no longer used by anyone.
|
||||
*/
|
||||
void unregister_sysctl_table(struct ctl_table_header * header)
|
||||
{
|
||||
might_sleep();
|
||||
|
||||
if (header == NULL)
|
||||
return;
|
||||
|
||||
spin_lock(&sysctl_lock);
|
||||
start_unregistering(header);
|
||||
if (!--header->parent->count) {
|
||||
WARN_ON(1);
|
||||
kfree_rcu(header->parent, rcu);
|
||||
}
|
||||
if (!--header->count)
|
||||
kfree_rcu(header, rcu);
|
||||
spin_unlock(&sysctl_lock);
|
||||
}
|
||||
|
||||
int sysctl_is_seen(struct ctl_table_header *p)
|
||||
{
|
||||
struct ctl_table_set *set = p->set;
|
||||
int res;
|
||||
spin_lock(&sysctl_lock);
|
||||
if (p->unregistering)
|
||||
res = 0;
|
||||
else if (!set->is_seen)
|
||||
res = 1;
|
||||
else
|
||||
res = set->is_seen(set);
|
||||
spin_unlock(&sysctl_lock);
|
||||
return res;
|
||||
}
|
||||
|
||||
void setup_sysctl_set(struct ctl_table_set *p,
|
||||
struct ctl_table_set *parent,
|
||||
int (*is_seen)(struct ctl_table_set *))
|
||||
{
|
||||
INIT_LIST_HEAD(&p->list);
|
||||
p->parent = parent ? parent : &sysctl_table_root.default_set;
|
||||
p->is_seen = is_seen;
|
||||
}
|
||||
|
||||
#else /* !CONFIG_SYSCTL */
|
||||
struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
|
||||
{
|
||||
return NULL;
|
||||
}
|
||||
|
||||
struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
|
||||
struct ctl_table *table)
|
||||
{
|
||||
return NULL;
|
||||
}
|
||||
|
||||
void unregister_sysctl_table(struct ctl_table_header * table)
|
||||
{
|
||||
}
|
||||
|
||||
void setup_sysctl_set(struct ctl_table_set *p,
|
||||
struct ctl_table_set *parent,
|
||||
int (*is_seen)(struct ctl_table_set *))
|
||||
{
|
||||
}
|
||||
|
||||
void sysctl_head_put(struct ctl_table_header *head)
|
||||
{
|
||||
}
|
||||
|
||||
#endif /* CONFIG_SYSCTL */
|
||||
|
||||
/*
|
||||
|
@ -3009,6 +2517,3 @@ EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
|
|||
EXPORT_SYMBOL(proc_dostring);
|
||||
EXPORT_SYMBOL(proc_doulongvec_minmax);
|
||||
EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
|
||||
EXPORT_SYMBOL(register_sysctl_table);
|
||||
EXPORT_SYMBOL(register_sysctl_paths);
|
||||
EXPORT_SYMBOL(unregister_sysctl_table);
|
||||
|
|
|
@ -1,160 +0,0 @@
|
|||
#include <linux/stat.h>
|
||||
#include <linux/sysctl.h>
|
||||
#include "../fs/xfs/xfs_sysctl.h"
|
||||
#include <linux/sunrpc/debug.h>
|
||||
#include <linux/string.h>
|
||||
#include <net/ip_vs.h>
|
||||
|
||||
|
||||
static int sysctl_depth(struct ctl_table *table)
|
||||
{
|
||||
struct ctl_table *tmp;
|
||||
int depth;
|
||||
|
||||
depth = 0;
|
||||
for (tmp = table; tmp->parent; tmp = tmp->parent)
|
||||
depth++;
|
||||
|
||||
return depth;
|
||||
}
|
||||
|
||||
static struct ctl_table *sysctl_parent(struct ctl_table *table, int n)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; table && i < n; i++)
|
||||
table = table->parent;
|
||||
|
||||
return table;
|
||||
}
|
||||
|
||||
|
||||
static void sysctl_print_path(struct ctl_table *table)
|
||||
{
|
||||
struct ctl_table *tmp;
|
||||
int depth, i;
|
||||
depth = sysctl_depth(table);
|
||||
if (table->procname) {
|
||||
for (i = depth; i >= 0; i--) {
|
||||
tmp = sysctl_parent(table, i);
|
||||
printk("/%s", tmp->procname?tmp->procname:"");
|
||||
}
|
||||
}
|
||||
printk(" ");
|
||||
}
|
||||
|
||||
static struct ctl_table *sysctl_check_lookup(struct nsproxy *namespaces,
|
||||
struct ctl_table *table)
|
||||
{
|
||||
struct ctl_table_header *head;
|
||||
struct ctl_table *ref, *test;
|
||||
int depth, cur_depth;
|
||||
|
||||
depth = sysctl_depth(table);
|
||||
|
||||
for (head = __sysctl_head_next(namespaces, NULL); head;
|
||||
head = __sysctl_head_next(namespaces, head)) {
|
||||
cur_depth = depth;
|
||||
ref = head->ctl_table;
|
||||
repeat:
|
||||
test = sysctl_parent(table, cur_depth);
|
||||
for (; ref->procname; ref++) {
|
||||
int match = 0;
|
||||
if (cur_depth && !ref->child)
|
||||
continue;
|
||||
|
||||
if (test->procname && ref->procname &&
|
||||
(strcmp(test->procname, ref->procname) == 0))
|
||||
match++;
|
||||
|
||||
if (match) {
|
||||
if (cur_depth != 0) {
|
||||
cur_depth--;
|
||||
ref = ref->child;
|
||||
goto repeat;
|
||||
}
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
}
|
||||
ref = NULL;
|
||||
out:
|
||||
sysctl_head_finish(head);
|
||||
return ref;
|
||||
}
|
||||
|
||||
static void set_fail(const char **fail, struct ctl_table *table, const char *str)
|
||||
{
|
||||
if (*fail) {
|
||||
printk(KERN_ERR "sysctl table check failed: ");
|
||||
sysctl_print_path(table);
|
||||
printk(" %s\n", *fail);
|
||||
dump_stack();
|
||||
}
|
||||
*fail = str;
|
||||
}
|
||||
|
||||
static void sysctl_check_leaf(struct nsproxy *namespaces,
|
||||
struct ctl_table *table, const char **fail)
|
||||
{
|
||||
struct ctl_table *ref;
|
||||
|
||||
ref = sysctl_check_lookup(namespaces, table);
|
||||
if (ref && (ref != table))
|
||||
set_fail(fail, table, "Sysctl already exists");
|
||||
}
|
||||
|
||||
int sysctl_check_table(struct nsproxy *namespaces, struct ctl_table *table)
|
||||
{
|
||||
int error = 0;
|
||||
for (; table->procname; table++) {
|
||||
const char *fail = NULL;
|
||||
|
||||
if (table->parent) {
|
||||
if (!table->parent->procname)
|
||||
set_fail(&fail, table, "Parent without procname");
|
||||
}
|
||||
if (table->child) {
|
||||
if (table->data)
|
||||
set_fail(&fail, table, "Directory with data?");
|
||||
if (table->maxlen)
|
||||
set_fail(&fail, table, "Directory with maxlen?");
|
||||
if ((table->mode & (S_IRUGO|S_IXUGO)) != table->mode)
|
||||
set_fail(&fail, table, "Writable sysctl directory");
|
||||
if (table->proc_handler)
|
||||
set_fail(&fail, table, "Directory with proc_handler");
|
||||
if (table->extra1)
|
||||
set_fail(&fail, table, "Directory with extra1");
|
||||
if (table->extra2)
|
||||
set_fail(&fail, table, "Directory with extra2");
|
||||
} else {
|
||||
if ((table->proc_handler == proc_dostring) ||
|
||||
(table->proc_handler == proc_dointvec) ||
|
||||
(table->proc_handler == proc_dointvec_minmax) ||
|
||||
(table->proc_handler == proc_dointvec_jiffies) ||
|
||||
(table->proc_handler == proc_dointvec_userhz_jiffies) ||
|
||||
(table->proc_handler == proc_dointvec_ms_jiffies) ||
|
||||
(table->proc_handler == proc_doulongvec_minmax) ||
|
||||
(table->proc_handler == proc_doulongvec_ms_jiffies_minmax)) {
|
||||
if (!table->data)
|
||||
set_fail(&fail, table, "No data");
|
||||
if (!table->maxlen)
|
||||
set_fail(&fail, table, "No maxlen");
|
||||
}
|
||||
#ifdef CONFIG_PROC_SYSCTL
|
||||
if (!table->proc_handler)
|
||||
set_fail(&fail, table, "No proc_handler");
|
||||
#endif
|
||||
sysctl_check_leaf(namespaces, table, &fail);
|
||||
}
|
||||
if (table->mode > 0777)
|
||||
set_fail(&fail, table, "bogus .mode");
|
||||
if (fail) {
|
||||
set_fail(&fail, table, NULL);
|
||||
error = -EINVAL;
|
||||
}
|
||||
if (table->child)
|
||||
error |= sysctl_check_table(namespaces, table->child);
|
||||
}
|
||||
return error;
|
||||
}
|
|
@ -1141,14 +1141,6 @@ config LATENCYTOP
|
|||
Enable this option if you want to use the LatencyTOP tool
|
||||
to find out which userspace is blocking on what kernel operations.
|
||||
|
||||
config SYSCTL_SYSCALL_CHECK
|
||||
bool "Sysctl checks"
|
||||
depends on SYSCTL
|
||||
---help---
|
||||
sys_sysctl uses binary paths that have been found challenging
|
||||
to properly maintain and use. This enables checks that help
|
||||
you to keep things correct.
|
||||
|
||||
source mm/Kconfig.debug
|
||||
source kernel/trace/Kconfig
|
||||
|
||||
|
|
|
@ -74,15 +74,13 @@ static struct ctl_table_root net_sysctl_ro_root = {
|
|||
|
||||
static int __net_init sysctl_net_init(struct net *net)
|
||||
{
|
||||
setup_sysctl_set(&net->sysctls,
|
||||
&net_sysctl_ro_root.default_set,
|
||||
is_seen);
|
||||
setup_sysctl_set(&net->sysctls, &net_sysctl_root, is_seen);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __net_exit sysctl_net_exit(struct net *net)
|
||||
{
|
||||
WARN_ON(!list_empty(&net->sysctls.list));
|
||||
retire_sysctl_set(&net->sysctls);
|
||||
}
|
||||
|
||||
static struct pernet_operations sysctl_pernet_ops = {
|
||||
|
@ -90,36 +88,32 @@ static struct pernet_operations sysctl_pernet_ops = {
|
|||
.exit = sysctl_net_exit,
|
||||
};
|
||||
|
||||
static __init int sysctl_init(void)
|
||||
static __init int net_sysctl_init(void)
|
||||
{
|
||||
int ret;
|
||||
ret = register_pernet_subsys(&sysctl_pernet_ops);
|
||||
if (ret)
|
||||
goto out;
|
||||
register_sysctl_root(&net_sysctl_root);
|
||||
setup_sysctl_set(&net_sysctl_ro_root.default_set, NULL, NULL);
|
||||
setup_sysctl_set(&net_sysctl_ro_root.default_set, &net_sysctl_ro_root, NULL);
|
||||
register_sysctl_root(&net_sysctl_ro_root);
|
||||
register_sysctl_root(&net_sysctl_root);
|
||||
out:
|
||||
return ret;
|
||||
}
|
||||
subsys_initcall(sysctl_init);
|
||||
subsys_initcall(net_sysctl_init);
|
||||
|
||||
struct ctl_table_header *register_net_sysctl_table(struct net *net,
|
||||
const struct ctl_path *path, struct ctl_table *table)
|
||||
{
|
||||
struct nsproxy namespaces;
|
||||
namespaces = *current->nsproxy;
|
||||
namespaces.net_ns = net;
|
||||
return __register_sysctl_paths(&net_sysctl_root,
|
||||
&namespaces, path, table);
|
||||
return __register_sysctl_paths(&net->sysctls, path, table);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(register_net_sysctl_table);
|
||||
|
||||
struct ctl_table_header *register_net_sysctl_rotable(const
|
||||
struct ctl_path *path, struct ctl_table *table)
|
||||
{
|
||||
return __register_sysctl_paths(&net_sysctl_ro_root,
|
||||
&init_nsproxy, path, table);
|
||||
return __register_sysctl_paths(&net_sysctl_ro_root.default_set,
|
||||
path, table);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(register_net_sysctl_rotable);
|
||||
|
||||
|
|
Loading…
Reference in New Issue