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-rw-r--r--fs/debugfs/file.c119
-rw-r--r--fs/debugfs/inode.c118
2 files changed, 121 insertions, 116 deletions
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index 2340f6978d6..63146295153 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -21,6 +21,7 @@
#include <linux/debugfs.h>
#include <linux/io.h>
#include <linux/slab.h>
+#include <linux/atomic.h>
static ssize_t default_read_file(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
@@ -403,6 +404,47 @@ struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
}
EXPORT_SYMBOL_GPL(debugfs_create_size_t);
+static int debugfs_atomic_t_set(void *data, u64 val)
+{
+ atomic_set((atomic_t *)data, val);
+ return 0;
+}
+static int debugfs_atomic_t_get(void *data, u64 *val)
+{
+ *val = atomic_read((atomic_t *)data);
+ return 0;
+}
+DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t, debugfs_atomic_t_get,
+ debugfs_atomic_t_set, "%lld\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_ro, debugfs_atomic_t_get, NULL, "%lld\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_wo, NULL, debugfs_atomic_t_set, "%lld\n");
+
+/**
+ * debugfs_create_atomic_t - create a debugfs file that is used to read and
+ * write an atomic_t value
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have
+ * @parent: a pointer to the parent dentry for this file. This should be a
+ * directory dentry if set. If this parameter is %NULL, then the
+ * file will be created in the root of the debugfs filesystem.
+ * @value: a pointer to the variable that the file should read to and write
+ * from.
+ */
+struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
+ struct dentry *parent, atomic_t *value)
+{
+ /* if there are no write bits set, make read only */
+ if (!(mode & S_IWUGO))
+ return debugfs_create_file(name, mode, parent, value,
+ &fops_atomic_t_ro);
+ /* if there are no read bits set, make write only */
+ if (!(mode & S_IRUGO))
+ return debugfs_create_file(name, mode, parent, value,
+ &fops_atomic_t_wo);
+
+ return debugfs_create_file(name, mode, parent, value, &fops_atomic_t);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_atomic_t);
static ssize_t read_file_bool(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
@@ -431,6 +473,7 @@ static ssize_t write_file_bool(struct file *file, const char __user *user_buf,
if (copy_from_user(buf, user_buf, buf_size))
return -EFAULT;
+ buf[buf_size] = '\0';
if (strtobool(buf, &bv) == 0)
*val = bv;
@@ -526,73 +569,51 @@ struct array_data {
u32 elements;
};
-static int u32_array_open(struct inode *inode, struct file *file)
-{
- file->private_data = NULL;
- return nonseekable_open(inode, file);
-}
-
-static size_t format_array(char *buf, size_t bufsize, const char *fmt,
- u32 *array, u32 array_size)
+static size_t u32_format_array(char *buf, size_t bufsize,
+ u32 *array, int array_size)
{
size_t ret = 0;
- u32 i;
- for (i = 0; i < array_size; i++) {
+ while (--array_size >= 0) {
size_t len;
+ char term = array_size ? ' ' : '\n';
- len = snprintf(buf, bufsize, fmt, array[i]);
- len++; /* ' ' or '\n' */
+ len = snprintf(buf, bufsize, "%u%c", *array++, term);
ret += len;
- if (buf) {
- buf += len;
- bufsize -= len;
- buf[-1] = (i == array_size-1) ? '\n' : ' ';
- }
+ buf += len;
+ bufsize -= len;
}
-
- ret++; /* \0 */
- if (buf)
- *buf = '\0';
-
return ret;
}
-static char *format_array_alloc(const char *fmt, u32 *array,
- u32 array_size)
+static int u32_array_open(struct inode *inode, struct file *file)
{
- size_t len = format_array(NULL, 0, fmt, array, array_size);
- char *ret;
-
- ret = kmalloc(len, GFP_KERNEL);
- if (ret == NULL)
- return NULL;
+ struct array_data *data = inode->i_private;
+ int size, elements = data->elements;
+ char *buf;
+
+ /*
+ * Max size:
+ * - 10 digits + ' '/'\n' = 11 bytes per number
+ * - terminating NUL character
+ */
+ size = elements*11;
+ buf = kmalloc(size+1, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ buf[size] = 0;
+
+ file->private_data = buf;
+ u32_format_array(buf, size, data->array, data->elements);
- format_array(ret, len, fmt, array, array_size);
- return ret;
+ return nonseekable_open(inode, file);
}
static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
- struct inode *inode = file->f_path.dentry->d_inode;
- struct array_data *data = inode->i_private;
- size_t size;
-
- if (*ppos == 0) {
- if (file->private_data) {
- kfree(file->private_data);
- file->private_data = NULL;
- }
-
- file->private_data = format_array_alloc("%u", data->array,
- data->elements);
- }
-
- size = 0;
- if (file->private_data)
- size = strlen(file->private_data);
+ size_t size = strlen(file->private_data);
return simple_read_from_buffer(buf, len, ppos,
file->private_data, size);
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index d17c20fd74e..8c41b52da35 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -28,7 +28,7 @@
#include <linux/magic.h>
#include <linux/slab.h>
-#define DEBUGFS_DEFAULT_MODE 0755
+#define DEBUGFS_DEFAULT_MODE 0700
static struct vfsmount *debugfs_mount;
static int debugfs_mount_count;
@@ -59,7 +59,6 @@ static struct inode *debugfs_get_inode(struct super_block *sb, umode_t mode, dev
case S_IFDIR:
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
- inode->i_private = NULL;
/* directory inodes start off with i_nlink == 2
* (for "." entry) */
@@ -128,8 +127,8 @@ static inline int debugfs_positive(struct dentry *dentry)
}
struct debugfs_mount_opts {
- uid_t uid;
- gid_t gid;
+ kuid_t uid;
+ kgid_t gid;
umode_t mode;
};
@@ -156,6 +155,8 @@ static int debugfs_parse_options(char *data, struct debugfs_mount_opts *opts)
substring_t args[MAX_OPT_ARGS];
int option;
int token;
+ kuid_t uid;
+ kgid_t gid;
char *p;
opts->mode = DEBUGFS_DEFAULT_MODE;
@@ -169,12 +170,18 @@ static int debugfs_parse_options(char *data, struct debugfs_mount_opts *opts)
case Opt_uid:
if (match_int(&args[0], &option))
return -EINVAL;
- opts->uid = option;
+ uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(uid))
+ return -EINVAL;
+ opts->uid = uid;
break;
case Opt_gid:
- if (match_octal(&args[0], &option))
+ if (match_int(&args[0], &option))
+ return -EINVAL;
+ gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(gid))
return -EINVAL;
- opts->gid = option;
+ opts->gid = gid;
break;
case Opt_mode:
if (match_octal(&args[0], &option))
@@ -211,6 +218,7 @@ static int debugfs_remount(struct super_block *sb, int *flags, char *data)
int err;
struct debugfs_fs_info *fsi = sb->s_fs_info;
+ sync_filesystem(sb);
err = debugfs_parse_options(data, &fsi->mount_opts);
if (err)
goto fail;
@@ -226,10 +234,12 @@ static int debugfs_show_options(struct seq_file *m, struct dentry *root)
struct debugfs_fs_info *fsi = root->d_sb->s_fs_info;
struct debugfs_mount_opts *opts = &fsi->mount_opts;
- if (opts->uid != 0)
- seq_printf(m, ",uid=%u", opts->uid);
- if (opts->gid != 0)
- seq_printf(m, ",gid=%u", opts->gid);
+ if (!uid_eq(opts->uid, GLOBAL_ROOT_UID))
+ seq_printf(m, ",uid=%u",
+ from_kuid_munged(&init_user_ns, opts->uid));
+ if (!gid_eq(opts->gid, GLOBAL_ROOT_GID))
+ seq_printf(m, ",gid=%u",
+ from_kgid_munged(&init_user_ns, opts->gid));
if (opts->mode != DEBUGFS_DEFAULT_MODE)
seq_printf(m, ",mode=%o", opts->mode);
@@ -290,10 +300,11 @@ static struct file_system_type debug_fs_type = {
.mount = debug_mount,
.kill_sb = kill_litter_super,
};
+MODULE_ALIAS_FS("debugfs");
-struct dentry *__create_file(const char *name, umode_t mode,
- struct dentry *parent, void *data,
- const struct file_operations *fops)
+static struct dentry *__create_file(const char *name, umode_t mode,
+ struct dentry *parent, void *data,
+ const struct file_operations *fops)
{
struct dentry *dentry = NULL;
int error;
@@ -313,7 +324,6 @@ struct dentry *__create_file(const char *name, umode_t mode,
if (!parent)
parent = debugfs_mount->mnt_root;
- dentry = NULL;
mutex_lock(&parent->d_inode->i_mutex);
dentry = lookup_one_len(name, parent, strlen(name));
if (!IS_ERR(dentry)) {
@@ -349,7 +359,7 @@ exit:
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have.
* @parent: a pointer to the parent dentry for this file. This should be a
- * directory dentry if set. If this paramater is NULL, then the
+ * directory dentry if set. If this parameter is NULL, then the
* file will be created in the root of the debugfs filesystem.
* @data: a pointer to something that the caller will want to get to later
* on. The inode.i_private pointer will point to this value on
@@ -391,7 +401,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_file);
* @name: a pointer to a string containing the name of the directory to
* create.
* @parent: a pointer to the parent dentry for this file. This should be a
- * directory dentry if set. If this paramater is NULL, then the
+ * directory dentry if set. If this parameter is NULL, then the
* directory will be created in the root of the debugfs filesystem.
*
* This function creates a directory in debugfs with the given name.
@@ -416,7 +426,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_dir);
* @name: a pointer to a string containing the name of the symbolic link to
* create.
* @parent: a pointer to the parent dentry for this symbolic link. This
- * should be a directory dentry if set. If this paramater is NULL,
+ * should be a directory dentry if set. If this parameter is NULL,
* then the symbolic link will be created in the root of the debugfs
* filesystem.
* @target: a pointer to a string containing the path to the target of the
@@ -495,7 +505,7 @@ void debugfs_remove(struct dentry *dentry)
struct dentry *parent;
int ret;
- if (!dentry)
+ if (IS_ERR_OR_NULL(dentry))
return;
parent = dentry->d_parent;
@@ -524,10 +534,9 @@ EXPORT_SYMBOL_GPL(debugfs_remove);
*/
void debugfs_remove_recursive(struct dentry *dentry)
{
- struct dentry *child;
- struct dentry *parent;
+ struct dentry *child, *next, *parent;
- if (!dentry)
+ if (IS_ERR_OR_NULL(dentry))
return;
parent = dentry->d_parent;
@@ -535,61 +544,36 @@ void debugfs_remove_recursive(struct dentry *dentry)
return;
parent = dentry;
+ down:
mutex_lock(&parent->d_inode->i_mutex);
+ list_for_each_entry_safe(child, next, &parent->d_subdirs, d_u.d_child) {
+ if (!debugfs_positive(child))
+ continue;
- while (1) {
- /*
- * When all dentries under "parent" has been removed,
- * walk up the tree until we reach our starting point.
- */
- if (list_empty(&parent->d_subdirs)) {
- mutex_unlock(&parent->d_inode->i_mutex);
- if (parent == dentry)
- break;
- parent = parent->d_parent;
- mutex_lock(&parent->d_inode->i_mutex);
- }
- child = list_entry(parent->d_subdirs.next, struct dentry,
- d_u.d_child);
- next_sibling:
-
- /*
- * If "child" isn't empty, walk down the tree and
- * remove all its descendants first.
- */
+ /* perhaps simple_empty(child) makes more sense */
if (!list_empty(&child->d_subdirs)) {
mutex_unlock(&parent->d_inode->i_mutex);
parent = child;
- mutex_lock(&parent->d_inode->i_mutex);
- continue;
- }
- __debugfs_remove(child, parent);
- if (parent->d_subdirs.next == &child->d_u.d_child) {
- /*
- * Try the next sibling.
- */
- if (child->d_u.d_child.next != &parent->d_subdirs) {
- child = list_entry(child->d_u.d_child.next,
- struct dentry,
- d_u.d_child);
- goto next_sibling;
- }
-
- /*
- * Avoid infinite loop if we fail to remove
- * one dentry.
- */
- mutex_unlock(&parent->d_inode->i_mutex);
- break;
+ goto down;
}
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+ up:
+ if (!__debugfs_remove(child, parent))
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
}
- parent = dentry->d_parent;
+ mutex_unlock(&parent->d_inode->i_mutex);
+ child = parent;
+ parent = parent->d_parent;
mutex_lock(&parent->d_inode->i_mutex);
- __debugfs_remove(dentry, parent);
+
+ if (child != dentry) {
+ next = list_next_entry(child, d_u.d_child);
+ goto up;
+ }
+
+ if (!__debugfs_remove(child, parent))
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
mutex_unlock(&parent->d_inode->i_mutex);
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
}
EXPORT_SYMBOL_GPL(debugfs_remove_recursive);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 21:09:50 +0000