eCryptfs: Make all miscdev functions use daemon ptr in file private_data
Now that a pointer to a valid struct ecryptfs_daemon is stored in the
private_data of an opened /dev/ecryptfs file, the remaining miscdev
functions can utilize the pointer rather than looking up the
ecryptfs_daemon at the beginning of each operation.
The security model of /dev/ecryptfs is simplified a little bit with this
patch. Upon opening /dev/ecryptfs, a per-user ecryptfs_daemon is
registered. Another daemon cannot be registered for that user until the
last file reference is released. During the lifetime of the
ecryptfs_daemon, access checks are not performed on the /dev/ecryptfs
operations because it is assumed that the application securely handles
the opened file descriptor and does not unintentionally leak it to
processes that are not trusted.
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Cc: Sasha Levin <levinsasha928@gmail.com>
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index 01a1f85..0deb4f2 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -392,10 +392,7 @@
#define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
u32 flags;
u32 num_queued_msg_ctx;
- struct pid *pid;
- uid_t euid;
- struct user_namespace *user_ns;
- struct task_struct *task;
+ struct file *file;
struct mutex mux;
struct list_head msg_ctx_out_queue;
wait_queue_head_t wait;
@@ -619,9 +616,8 @@
ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
size_t size, int flags);
int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
-int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
- struct user_namespace *user_ns, struct pid *pid,
- u32 seq);
+int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
+ struct ecryptfs_message *msg, u32 seq);
int ecryptfs_send_message(char *data, int data_len,
struct ecryptfs_msg_ctx **msg_ctx);
int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
@@ -666,8 +662,7 @@
struct inode *ecryptfs_inode);
struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
-int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon, uid_t euid,
- struct user_namespace *user_ns);
+int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
size_t *length_size);
int ecryptfs_write_packet_length(char *dest, size_t size,
@@ -679,8 +674,7 @@
u16 msg_flags, struct ecryptfs_daemon *daemon);
void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
int
-ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, uid_t euid,
- struct user_namespace *user_ns, struct pid *pid);
+ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
int ecryptfs_init_kthread(void);
void ecryptfs_destroy_kthread(void);
int ecryptfs_privileged_open(struct file **lower_file,