Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 1c74a7c..848e0aa 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -35,6 +35,7 @@
static struct vfsmount *debugfs_mount;
static int debugfs_mount_count;
static bool debugfs_registered;
+static unsigned int debugfs_allow __ro_after_init = DEFAULT_DEBUGFS_ALLOW_BITS;
/*
* Don't allow access attributes to be changed whilst the kernel is locked down
@@ -266,6 +267,9 @@
int flags, const char *dev_name,
void *data)
{
+ if (!(debugfs_allow & DEBUGFS_ALLOW_API))
+ return ERR_PTR(-EPERM);
+
return mount_single(fs_type, flags, data, debug_fill_super);
}
@@ -299,13 +303,9 @@
if (!parent)
parent = debugfs_mount->mnt_root;
- dentry = lookup_one_len_unlocked(name, parent, strlen(name));
+ dentry = lookup_positive_unlocked(name, parent, strlen(name));
if (IS_ERR(dentry))
return NULL;
- if (!d_really_is_positive(dentry)) {
- dput(dentry);
- return NULL;
- }
return dentry;
}
EXPORT_SYMBOL_GPL(debugfs_lookup);
@@ -315,6 +315,9 @@
struct dentry *dentry;
int error;
+ if (!(debugfs_allow & DEBUGFS_ALLOW_API))
+ return ERR_PTR(-EPERM);
+
if (!debugfs_initialized())
return ERR_PTR(-ENOENT);
@@ -339,7 +342,10 @@
parent = debugfs_mount->mnt_root;
inode_lock(d_inode(parent));
- dentry = lookup_one_len(name, parent, strlen(name));
+ if (unlikely(IS_DEADDIR(d_inode(parent))))
+ dentry = ERR_PTR(-ENOENT);
+ else
+ dentry = lookup_one_len(name, parent, strlen(name));
if (!IS_ERR(dentry) && d_really_is_positive(dentry)) {
if (d_is_dir(dentry))
pr_err("Directory '%s' with parent '%s' already present!\n",
@@ -389,6 +395,11 @@
if (IS_ERR(dentry))
return dentry;
+ if (!(debugfs_allow & DEBUGFS_ALLOW_API)) {
+ failed_creating(dentry);
+ return ERR_PTR(-EPERM);
+ }
+
inode = debugfs_get_inode(dentry->d_sb);
if (unlikely(!inode)) {
pr_err("out of free dentries, can not create file '%s'\n",
@@ -430,7 +441,7 @@
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.) If an error occurs, %ERR_PTR(-ERROR) will be
+ * you are responsible here.) If an error occurs, ERR_PTR(-ERROR) will be
* returned.
*
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
@@ -505,26 +516,16 @@
* wide range of flexibility in creating a file, or a directory (if you want
* to create a directory, the debugfs_create_dir() function is
* recommended to be used instead.)
- *
- * This function will return a pointer to a dentry if it succeeds. This
- * pointer must be passed to the debugfs_remove() function when the file is
- * to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.) If an error occurs, %ERR_PTR(-ERROR) will be
- * returned.
- *
- * If debugfs is not enabled in the kernel, the value -%ENODEV will be
- * returned.
*/
-struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
- struct dentry *parent, void *data,
- const struct file_operations *fops,
- loff_t file_size)
+void debugfs_create_file_size(const char *name, umode_t mode,
+ struct dentry *parent, void *data,
+ const struct file_operations *fops,
+ loff_t file_size)
{
struct dentry *de = debugfs_create_file(name, mode, parent, data, fops);
- if (de)
+ if (!IS_ERR(de))
d_inode(de)->i_size = file_size;
- return de;
}
EXPORT_SYMBOL_GPL(debugfs_create_file_size);
@@ -541,7 +542,7 @@
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.) If an error occurs, %ERR_PTR(-ERROR) will be
+ * you are responsible here.) If an error occurs, ERR_PTR(-ERROR) will be
* returned.
*
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
@@ -555,6 +556,11 @@
if (IS_ERR(dentry))
return dentry;
+ if (!(debugfs_allow & DEBUGFS_ALLOW_API)) {
+ failed_creating(dentry);
+ return ERR_PTR(-EPERM);
+ }
+
inode = debugfs_get_inode(dentry->d_sb);
if (unlikely(!inode)) {
pr_err("out of free dentries, can not create directory '%s'\n",
@@ -597,6 +603,11 @@
if (IS_ERR(dentry))
return dentry;
+ if (!(debugfs_allow & DEBUGFS_ALLOW_API)) {
+ failed_creating(dentry);
+ return ERR_PTR(-EPERM);
+ }
+
inode = debugfs_get_inode(dentry->d_sb);
if (unlikely(!inode)) {
pr_err("out of free dentries, can not create automount '%s'\n",
@@ -634,7 +645,7 @@
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the symbolic
* link is to be removed (no automatic cleanup happens if your module is
- * unloaded, you are responsible here.) If an error occurs, %ERR_PTR(-ERROR)
+ * unloaded, you are responsible here.) If an error occurs, ERR_PTR(-ERROR)
* will be returned.
*
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
@@ -688,62 +699,15 @@
wait_for_completion(&fsd->active_users_drained);
}
-static int __debugfs_remove(struct dentry *dentry, struct dentry *parent)
+static void remove_one(struct dentry *victim)
{
- int ret = 0;
-
- if (simple_positive(dentry)) {
- dget(dentry);
- if (d_is_dir(dentry)) {
- ret = simple_rmdir(d_inode(parent), dentry);
- if (!ret)
- fsnotify_rmdir(d_inode(parent), dentry);
- } else {
- simple_unlink(d_inode(parent), dentry);
- fsnotify_unlink(d_inode(parent), dentry);
- }
- if (!ret)
- d_delete(dentry);
- if (d_is_reg(dentry))
- __debugfs_file_removed(dentry);
- dput(dentry);
- }
- return ret;
+ if (d_is_reg(victim))
+ __debugfs_file_removed(victim);
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
}
/**
- * debugfs_remove - removes a file or directory from the debugfs filesystem
- * @dentry: a pointer to a the dentry of the file or directory to be
- * removed. If this parameter is NULL or an error value, nothing
- * will be done.
- *
- * This function removes a file or directory in debugfs that was previously
- * created with a call to another debugfs function (like
- * debugfs_create_file() or variants thereof.)
- *
- * This function is required to be called in order for the file to be
- * removed, no automatic cleanup of files will happen when a module is
- * removed, you are responsible here.
- */
-void debugfs_remove(struct dentry *dentry)
-{
- struct dentry *parent;
- int ret;
-
- if (IS_ERR_OR_NULL(dentry))
- return;
-
- parent = dentry->d_parent;
- inode_lock(d_inode(parent));
- ret = __debugfs_remove(dentry, parent);
- inode_unlock(d_inode(parent));
- if (!ret)
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
-}
-EXPORT_SYMBOL_GPL(debugfs_remove);
-
-/**
- * debugfs_remove_recursive - recursively removes a directory
+ * debugfs_remove - recursively removes a directory
* @dentry: a pointer to a the dentry of the directory to be removed. If this
* parameter is NULL or an error value, nothing will be done.
*
@@ -755,65 +719,16 @@
* removed, no automatic cleanup of files will happen when a module is
* removed, you are responsible here.
*/
-void debugfs_remove_recursive(struct dentry *dentry)
+void debugfs_remove(struct dentry *dentry)
{
- struct dentry *child, *parent;
-
if (IS_ERR_OR_NULL(dentry))
return;
- parent = dentry;
- down:
- inode_lock(d_inode(parent));
- loop:
- /*
- * The parent->d_subdirs is protected by the d_lock. Outside that
- * lock, the child can be unlinked and set to be freed which can
- * use the d_u.d_child as the rcu head and corrupt this list.
- */
- spin_lock(&parent->d_lock);
- list_for_each_entry(child, &parent->d_subdirs, d_child) {
- if (!simple_positive(child))
- continue;
-
- /* perhaps simple_empty(child) makes more sense */
- if (!list_empty(&child->d_subdirs)) {
- spin_unlock(&parent->d_lock);
- inode_unlock(d_inode(parent));
- parent = child;
- goto down;
- }
-
- spin_unlock(&parent->d_lock);
-
- if (!__debugfs_remove(child, parent))
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
-
- /*
- * The parent->d_lock protects agaist child from unlinking
- * from d_subdirs. When releasing the parent->d_lock we can
- * no longer trust that the next pointer is valid.
- * Restart the loop. We'll skip this one with the
- * simple_positive() check.
- */
- goto loop;
- }
- spin_unlock(&parent->d_lock);
-
- inode_unlock(d_inode(parent));
- child = parent;
- parent = parent->d_parent;
- inode_lock(d_inode(parent));
-
- if (child != dentry)
- /* go up */
- goto loop;
-
- if (!__debugfs_remove(child, parent))
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
- inode_unlock(d_inode(parent));
+ simple_pin_fs(&debug_fs_type, &debugfs_mount, &debugfs_mount_count);
+ simple_recursive_removal(dentry, remove_one);
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
}
-EXPORT_SYMBOL_GPL(debugfs_remove_recursive);
+EXPORT_SYMBOL_GPL(debugfs_remove);
/**
* debugfs_rename - rename a file/directory in the debugfs filesystem
@@ -896,10 +811,27 @@
}
EXPORT_SYMBOL_GPL(debugfs_initialized);
+static int __init debugfs_kernel(char *str)
+{
+ if (str) {
+ if (!strcmp(str, "on"))
+ debugfs_allow = DEBUGFS_ALLOW_API | DEBUGFS_ALLOW_MOUNT;
+ else if (!strcmp(str, "no-mount"))
+ debugfs_allow = DEBUGFS_ALLOW_API;
+ else if (!strcmp(str, "off"))
+ debugfs_allow = 0;
+ }
+
+ return 0;
+}
+early_param("debugfs", debugfs_kernel);
static int __init debugfs_init(void)
{
int retval;
+ if (!(debugfs_allow & DEBUGFS_ALLOW_MOUNT))
+ return -EPERM;
+
retval = sysfs_create_mount_point(kernel_kobj, "debug");
if (retval)
return retval;
@@ -913,4 +845,3 @@
return retval;
}
core_initcall(debugfs_init);
-