Merge "Fix recursive locking bug." into klp-dev (5856fd89) · Commits · e / os / android_system_core

sdcard/sdcard.c

+36 −21

Original line number	Diff line number	Diff line
		@@ -486,12 +486,18 @@ static void derive_permissions_locked(struct fuse* fuse, struct node *parent,
		}
		}

		/* Return if the calling UID holds sdcard_rw. */
		static bool get_caller_has_rw_locked(struct fuse* fuse, const struct fuse_in_header *hdr) {
		appid_t appid = multiuser_get_app_id(hdr->uid);
		return hashmapContainsKey(fuse->appid_with_rw, (void*) appid);
		}

		/* Kernel has already enforced everything we returned through
		* derive_permissions_locked(), so this is used to lock down access
		* even further, such as enforcing that apps hold sdcard_rw. */
		static bool check_caller_access_to_name(struct fuse* fuse,
		const struct fuse_in_header hdr, const struct node parent_node,
		const char* name, int mode) {
		const char* name, int mode, bool has_rw) {
		/* Always block security-sensitive files at root */
		if (parent_node && parent_node->perm == PERM_ROOT) {
		if (!strcmp(name, "autorun.inf")
		@@ -518,13 +524,7 @@ static bool check_caller_access_to_name(struct fuse* fuse,
		return true;
		}

		appid_t appid = multiuser_get_app_id(hdr->uid);

		pthread_mutex_lock(&fuse->lock);
		bool hasRw = hashmapContainsKey(fuse->appid_with_rw, (void*) appid);
		pthread_mutex_unlock(&fuse->lock);

		return hasRw;
		return has_rw;
		}

		/* No extra permissions to enforce */
		@@ -532,8 +532,8 @@ static bool check_caller_access_to_name(struct fuse* fuse,
		}

		static bool check_caller_access_to_node(struct fuse* fuse,
		const struct fuse_in_header hdr, const struct node node, int mode) {
		return check_caller_access_to_name(fuse, hdr, node->parent, node->name, mode);
		const struct fuse_in_header hdr, const struct node node, int mode, bool has_rw) {
		return check_caller_access_to_name(fuse, hdr, node->parent, node->name, mode, has_rw);
		}

		struct node create_node_locked(struct fuse fuse,
		@@ -831,7 +831,7 @@ static int handle_lookup(struct fuse* fuse, struct fuse_handler* handler,
		child_path, sizeof(child_path), 1))) {
		return -ENOENT;
		}
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, R_OK)) {
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, R_OK, false)) {
		return -EACCES;
		}

		@@ -872,7 +872,7 @@ static int handle_getattr(struct fuse* fuse, struct fuse_handler* handler,
		if (!node) {
		return -ENOENT;
		}
		if (!check_caller_access_to_node(fuse, hdr, node, R_OK)) {
		if (!check_caller_access_to_node(fuse, hdr, node, R_OK, false)) {
		return -EACCES;
		}

		@@ -882,11 +882,13 @@ static int handle_getattr(struct fuse* fuse, struct fuse_handler* handler,
		static int handle_setattr(struct fuse* fuse, struct fuse_handler* handler,
		const struct fuse_in_header hdr, const struct fuse_setattr_in req)
		{
		bool has_rw;
		struct node* node;
		char path[PATH_MAX];
		struct timespec times[2];

		pthread_mutex_lock(&fuse->lock);
		has_rw = get_caller_has_rw_locked(fuse, hdr);
		node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, path, sizeof(path));
		TRACE("[%d] SETATTR fh=%llx valid=%x @ %llx (%s)\n", handler->token,
		req->fh, req->valid, hdr->nodeid, node ? node->name : "?");
		@@ -895,7 +897,7 @@ static int handle_setattr(struct fuse* fuse, struct fuse_handler* handler,
		if (!node) {
		return -ENOENT;
		}
		if (!check_caller_access_to_node(fuse, hdr, node, W_OK)) {
		if (!check_caller_access_to_node(fuse, hdr, node, W_OK, has_rw)) {
		return -EACCES;
		}

		@@ -943,12 +945,14 @@ static int handle_setattr(struct fuse* fuse, struct fuse_handler* handler,
		static int handle_mknod(struct fuse* fuse, struct fuse_handler* handler,
		const struct fuse_in_header* hdr, const struct fuse_mknod_in* req, const char* name)
		{
		bool has_rw;
		struct node* parent_node;
		char parent_path[PATH_MAX];
		char child_path[PATH_MAX];
		const char* actual_name;

		pthread_mutex_lock(&fuse->lock);
		has_rw = get_caller_has_rw_locked(fuse, hdr);
		parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid,
		parent_path, sizeof(parent_path));
		TRACE("[%d] MKNOD %s 0%o @ %llx (%s)\n", handler->token,
		@@ -959,7 +963,7 @@ static int handle_mknod(struct fuse* fuse, struct fuse_handler* handler,
		child_path, sizeof(child_path), 1))) {
		return -ENOENT;
		}
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK)) {
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) {
		return -EACCES;
		}
		__u32 mode = (req->mode & (~0777)) \| 0664;
		@@ -972,12 +976,14 @@ static int handle_mknod(struct fuse* fuse, struct fuse_handler* handler,
		static int handle_mkdir(struct fuse* fuse, struct fuse_handler* handler,
		const struct fuse_in_header* hdr, const struct fuse_mkdir_in* req, const char* name)
		{
		bool has_rw;
		struct node* parent_node;
		char parent_path[PATH_MAX];
		char child_path[PATH_MAX];
		const char* actual_name;

		pthread_mutex_lock(&fuse->lock);
		has_rw = get_caller_has_rw_locked(fuse, hdr);
		parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid,
		parent_path, sizeof(parent_path));
		TRACE("[%d] MKDIR %s 0%o @ %llx (%s)\n", handler->token,
		@@ -988,7 +994,7 @@ static int handle_mkdir(struct fuse* fuse, struct fuse_handler* handler,
		child_path, sizeof(child_path), 1))) {
		return -ENOENT;
		}
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK)) {
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) {
		return -EACCES;
		}
		__u32 mode = (req->mode & (~0777)) \| 0775;
		@@ -1001,11 +1007,13 @@ static int handle_mkdir(struct fuse* fuse, struct fuse_handler* handler,
		static int handle_unlink(struct fuse* fuse, struct fuse_handler* handler,
		const struct fuse_in_header* hdr, const char* name)
		{
		bool has_rw;
		struct node* parent_node;
		char parent_path[PATH_MAX];
		char child_path[PATH_MAX];

		pthread_mutex_lock(&fuse->lock);
		has_rw = get_caller_has_rw_locked(fuse, hdr);
		parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid,
		parent_path, sizeof(parent_path));
		TRACE("[%d] UNLINK %s @ %llx (%s)\n", handler->token,
		@@ -1016,7 +1024,7 @@ static int handle_unlink(struct fuse* fuse, struct fuse_handler* handler,
		child_path, sizeof(child_path), 1)) {
		return -ENOENT;
		}
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK)) {
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) {
		return -EACCES;
		}
		if (unlink(child_path) < 0) {
		@@ -1028,11 +1036,13 @@ static int handle_unlink(struct fuse* fuse, struct fuse_handler* handler,
		static int handle_rmdir(struct fuse* fuse, struct fuse_handler* handler,
		const struct fuse_in_header* hdr, const char* name)
		{
		bool has_rw;
		struct node* parent_node;
		char parent_path[PATH_MAX];
		char child_path[PATH_MAX];

		pthread_mutex_lock(&fuse->lock);
		has_rw = get_caller_has_rw_locked(fuse, hdr);
		parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid,
		parent_path, sizeof(parent_path));
		TRACE("[%d] RMDIR %s @ %llx (%s)\n", handler->token,
		@@ -1043,7 +1053,7 @@ static int handle_rmdir(struct fuse* fuse, struct fuse_handler* handler,
		child_path, sizeof(child_path), 1)) {
		return -ENOENT;
		}
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK)) {
		if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) {
		return -EACCES;
		}
		if (rmdir(child_path) < 0) {
		@@ -1056,6 +1066,7 @@ static int handle_rename(struct fuse* fuse, struct fuse_handler* handler,
		const struct fuse_in_header* hdr, const struct fuse_rename_in* req,
		const char* old_name, const char* new_name)
		{
		bool has_rw;
		struct node* old_parent_node;
		struct node* new_parent_node;
		struct node* child_node;
		@@ -1067,6 +1078,7 @@ static int handle_rename(struct fuse* fuse, struct fuse_handler* handler,
		int res;

		pthread_mutex_lock(&fuse->lock);
		has_rw = get_caller_has_rw_locked(fuse, hdr);
		old_parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid,
		old_parent_path, sizeof(old_parent_path));
		new_parent_node = lookup_node_and_path_by_id_locked(fuse, req->newdir,
		@@ -1079,11 +1091,11 @@ static int handle_rename(struct fuse* fuse, struct fuse_handler* handler,
		res = -ENOENT;
		goto lookup_error;
		}
		if (!check_caller_access_to_name(fuse, hdr, old_parent_node, old_name, W_OK)) {
		if (!check_caller_access_to_name(fuse, hdr, old_parent_node, old_name, W_OK, has_rw)) {
		res = -EACCES;
		goto lookup_error;
		}
		if (!check_caller_access_to_name(fuse, hdr, new_parent_node, new_name, W_OK)) {
		if (!check_caller_access_to_name(fuse, hdr, new_parent_node, new_name, W_OK, has_rw)) {
		res = -EACCES;
		goto lookup_error;
		}
		@@ -1146,12 +1158,14 @@ static int open_flags_to_access_mode(int open_flags) {
		static int handle_open(struct fuse* fuse, struct fuse_handler* handler,
		const struct fuse_in_header* hdr, const struct fuse_open_in* req)
		{
		bool has_rw;
		struct node* node;
		char path[PATH_MAX];
		struct fuse_open_out out;
		struct handle *h;

		pthread_mutex_lock(&fuse->lock);
		has_rw = get_caller_has_rw_locked(fuse, hdr);
		node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, path, sizeof(path));
		TRACE("[%d] OPEN 0%o @ %llx (%s)\n", handler->token,
		req->flags, hdr->nodeid, node ? node->name : "?");
		@@ -1160,7 +1174,8 @@ static int handle_open(struct fuse* fuse, struct fuse_handler* handler,
		if (!node) {
		return -ENOENT;
		}
		if (!check_caller_access_to_node(fuse, hdr, node, open_flags_to_access_mode(req->flags))) {
		if (!check_caller_access_to_node(fuse, hdr, node,
		open_flags_to_access_mode(req->flags), has_rw)) {
		return -EACCES;
		}
		h = malloc(sizeof(*h));
		@@ -1307,7 +1322,7 @@ static int handle_opendir(struct fuse* fuse, struct fuse_handler* handler,
		if (!node) {
		return -ENOENT;
		}
		if (!check_caller_access_to_node(fuse, hdr, node, R_OK)) {
		if (!check_caller_access_to_node(fuse, hdr, node, R_OK, false)) {
		return -EACCES;
		}
		h = malloc(sizeof(*h));