[PATCH 7/9] fs: move namei sysctls to its own file

Luis Chamberlain
2021-11-29T22:51:34Z

So move namei's own sysctl knobs to its own file.

Other than the move we also avoid initializing two static
variables to 0 as this is not needed:

* sysctl_protected_symlinks
* sysctl_protected_hardlinks

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
fs/namei.c | 58 ++++++++++++++++++++++++++++++++++++++++++----
include/linux/fs.h | 1 -
kernel/sysctl.c | 36 ----------------------------
3 files changed, 54 insertions(+), 41 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 1f9d2187c765..8d4f832f94aa 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1020,10 +1020,60 @@ static inline void put_link(struct nameidata *nd)
path_put(&last->link);
}

-int sysctl_protected_symlinks __read_mostly = 0;
-int sysctl_protected_hardlinks __read_mostly = 0;
-int sysctl_protected_fifos __read_mostly;
-int sysctl_protected_regular __read_mostly;
+static int sysctl_protected_symlinks __read_mostly;
+static int sysctl_protected_hardlinks __read_mostly;
+static int sysctl_protected_fifos __read_mostly;
+static int sysctl_protected_regular __read_mostly;
+
+#ifdef CONFIG_SYSCTL
+static struct ctl_table namei_sysctls[] = {
+ {
+ .procname = "protected_symlinks",
+ .data = &sysctl_protected_symlinks,
+ .maxlen = sizeof(int),
+ .mode = 0600,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ {
+ .procname = "protected_hardlinks",
+ .data = &sysctl_protected_hardlinks,
+ .maxlen = sizeof(int),
+ .mode = 0600,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ {
+ .procname = "protected_fifos",
+ .data = &sysctl_protected_fifos,
+ .maxlen = sizeof(int),
+ .mode = 0600,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_TWO,
+ },
+ {
+ .procname = "protected_regular",
+ .data = &sysctl_protected_regular,
+ .maxlen = sizeof(int),
+ .mode = 0600,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_TWO,
+ },
+ { }
+};
+
+static int __init init_fs_namei_sysctls(void)
+{
+ register_sysctl_init("fs", namei_sysctls);
+ return 0;
+}
+fs_initcall(init_fs_namei_sysctls);
+
+#endif /* CONFIG_SYSCTL */

/**
* may_follow_link - Check symlink following for unsafe situations
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9ff634184f58..233b5ab38fe0 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -80,7 +80,6 @@ extern void __init files_maxfiles_init(void);

extern unsigned long get_max_files(void);
extern unsigned int sysctl_nr_open;
-extern int leases_enable, lease_break_time;

typedef __kernel_rwf_t rwf_t;

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 52a86746ac9d..39ba8e09ce31 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2896,42 +2896,6 @@ static struct ctl_table vm_table[] = {
};

static struct ctl_table fs_table[] = {
- {
- .procname = "protected_symlinks",
- .data = &sysctl_protected_symlinks,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
- {
- .procname = "protected_hardlinks",
- .data = &sysctl_protected_hardlinks,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
- },
- {
- .procname = "protected_fifos",
- .data = &sysctl_protected_fifos,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_TWO,
- },
- {
- .procname = "protected_regular",
- .data = &sysctl_protected_regular,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_TWO,
- },
{
.procname = "suid_dumpable",
.data = &suid_dumpable,
--
2.33.0