[PATCH] powerpc: Cope with duplicate node & property names in /proc/device-tree (5149fa47) · Commits · e / devices / android_kernel_fairphone_FP3

fs/proc/proc_devtree.c

+80 −23

Original line number	Original line	Diff line number	Diff line
	@@ -52,7 +52,8 @@ static int property_read_proc(char page, char *start, off_t off,
	* Add a property to a node		* Add a property to a node
	*/		*/
	static struct proc_dir_entry *		static struct proc_dir_entry *
	__proc_device_tree_add_prop(struct proc_dir_entry de, struct property pp)		__proc_device_tree_add_prop(struct proc_dir_entry de, struct property pp,
			const char *name)
	{		{
	struct proc_dir_entry *ent;		struct proc_dir_entry *ent;

	@@ -60,14 +61,14 @@ __proc_device_tree_add_prop(struct proc_dir_entry de, struct property pp)
	* Unfortunately proc_register puts each new entry		* Unfortunately proc_register puts each new entry
	* at the beginning of the list. So we rearrange them.		* at the beginning of the list. So we rearrange them.
	*/		*/
	ent = create_proc_read_entry(pp->name,		ent = create_proc_read_entry(name,
	strncmp(pp->name, "security-", 9)		strncmp(name, "security-", 9)
	? S_IRUGO : S_IRUSR, de,		? S_IRUGO : S_IRUSR, de,
	property_read_proc, pp);		property_read_proc, pp);
	if (ent == NULL)		if (ent == NULL)
	return NULL;		return NULL;

	if (!strncmp(pp->name, "security-", 9))		if (!strncmp(name, "security-", 9))
	ent->size = 0; /* don't leak number of password chars */		ent->size = 0; /* don't leak number of password chars */
	else		else
	ent->size = pp->length;		ent->size = pp->length;
	@@ -78,7 +79,7 @@ __proc_device_tree_add_prop(struct proc_dir_entry de, struct property pp)

	void proc_device_tree_add_prop(struct proc_dir_entry pde, struct property prop)		void proc_device_tree_add_prop(struct proc_dir_entry pde, struct property prop)
	{		{
	__proc_device_tree_add_prop(pde, prop);		__proc_device_tree_add_prop(pde, prop, prop->name);
	}		}

	void proc_device_tree_remove_prop(struct proc_dir_entry *pde,		void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
	@@ -105,6 +106,69 @@ void proc_device_tree_update_prop(struct proc_dir_entry *pde,
	}		}
	}		}

			/*
			* Various dodgy firmware might give us nodes and/or properties with
			* conflicting names. That's generally ok, except for exporting via /proc,
			* so munge names here to ensure they're unique.
			*/

			static int duplicate_name(struct proc_dir_entry de, const char name)
			{
			struct proc_dir_entry *ent;
			int found = 0;

			spin_lock(&proc_subdir_lock);

			for (ent = de->subdir; ent != NULL; ent = ent->next) {
			if (strcmp(ent->name, name) == 0) {
			found = 1;
			break;
			}
			}

			spin_unlock(&proc_subdir_lock);

			return found;
			}

			static const char fixup_name(struct device_node np, struct proc_dir_entry *de,
			const char *name)
			{
			char *fixed_name;
			int fixup_len = strlen(name) + 2 + 1; /* name + #x + \0 */
			int i = 1, size;

			realloc:
			fixed_name = kmalloc(fixup_len, GFP_KERNEL);
			if (fixed_name == NULL) {
			printk(KERN_ERR "device-tree: Out of memory trying to fixup "
			"name \"%s\"\n", name);
			return name;
			}

			retry:
			size = snprintf(fixed_name, fixup_len, "%s#%d", name, i);
			size++; /* account for NULL */

			if (size > fixup_len) {
			/* We ran out of space, free and reallocate. */
			kfree(fixed_name);
			fixup_len = size;
			goto realloc;
			}

			if (duplicate_name(de, fixed_name)) {
			/* Multiple duplicates. Retry with a different offset. */
			i++;
			goto retry;
			}

			printk(KERN_WARNING "device-tree: Duplicate name in %s, "
			"renamed to \"%s\"\n", np->full_name, fixed_name);

			return fixed_name;
			}

	/*		/*
	* Process a node, adding entries for its children and its properties.		* Process a node, adding entries for its children and its properties.
	*/		*/
	@@ -118,37 +182,30 @@ void proc_device_tree_add_node(struct device_node *np,

	set_node_proc_entry(np, de);		set_node_proc_entry(np, de);
	for (child = NULL; (child = of_get_next_child(np, child));) {		for (child = NULL; (child = of_get_next_child(np, child));) {
			/* Use everything after the last slash, or the full name */
	p = strrchr(child->full_name, '/');		p = strrchr(child->full_name, '/');
	if (!p)		if (!p)
	p = child->full_name;		p = child->full_name;
	else		else
	++p;		++p;

			if (duplicate_name(de, p))
			p = fixup_name(np, de, p);

	ent = proc_mkdir(p, de);		ent = proc_mkdir(p, de);
	if (ent == 0)		if (ent == 0)
	break;		break;
	proc_device_tree_add_node(child, ent);		proc_device_tree_add_node(child, ent);
	}		}
	of_node_put(child);		of_node_put(child);

	for (pp = np->properties; pp != 0; pp = pp->next) {		for (pp = np->properties; pp != 0; pp = pp->next) {
	/*		p = pp->name;
	* Yet another Apple device-tree bogosity: on some machines,
	* they have properties & nodes with the same name. Those		if (duplicate_name(de, p))
	* properties are quite unimportant for us though, thus we		p = fixup_name(np, de, p);
	* simply "skip" them here, but we do have to check.
	*/
	spin_lock(&proc_subdir_lock);
	for (ent = de->subdir; ent != NULL; ent = ent->next)
	if (!strcmp(ent->name, pp->name))
	break;
	spin_unlock(&proc_subdir_lock);
	if (ent != NULL) {
	printk(KERN_WARNING "device-tree: property \"%s\" name"
	" conflicts with node in %s\n", pp->name,
	np->full_name);
	continue;
	}

	ent = __proc_device_tree_add_prop(de, pp);		ent = __proc_device_tree_add_prop(de, pp, p);
	if (ent == 0)		if (ent == 0)
	break;		break;
	}		}