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-rw-r--r--fs/crypto/keyring.c29
-rw-r--r--include/linux/fscrypt.h8
-rw-r--r--include/uapi/linux/fscrypt.h1
3 files changed, 33 insertions, 5 deletions
diff --git a/fs/crypto/keyring.c b/fs/crypto/keyring.c
index c654effb83f5..8c600ead0e2e 100644
--- a/fs/crypto/keyring.c
+++ b/fs/crypto/keyring.c
@@ -11,6 +11,7 @@
*
* - FS_IOC_ADD_ENCRYPTION_KEY
* - FS_IOC_REMOVE_ENCRYPTION_KEY
+ * - FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS
* - FS_IOC_GET_ENCRYPTION_KEY_STATUS
*
* See the "User API" section of Documentation/filesystems/fscrypt.rst for more
@@ -699,8 +700,10 @@ static int try_to_lock_encrypted_files(struct super_block *sb,
/*
* Try to remove an fscrypt master encryption key.
*
- * This removes the current user's claim to the key, then removes the key itself
- * if no other users have claims.
+ * FS_IOC_REMOVE_ENCRYPTION_KEY (all_users=false) removes the current user's
+ * claim to the key, then removes the key itself if no other users have claims.
+ * FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS (all_users=true) always removes the
+ * key itself.
*
* To "remove the key itself", first we wipe the actual master key secret, so
* that no more inodes can be unlocked with it. Then we try to evict all cached
@@ -715,7 +718,7 @@ static int try_to_lock_encrypted_files(struct super_block *sb,
* For more details, see the "Removing keys" section of
* Documentation/filesystems/fscrypt.rst.
*/
-int fscrypt_ioctl_remove_key(struct file *filp, void __user *_uarg)
+static int do_remove_key(struct file *filp, void __user *_uarg, bool all_users)
{
struct super_block *sb = file_inode(filp)->i_sb;
struct fscrypt_remove_key_arg __user *uarg = _uarg;
@@ -751,9 +754,12 @@ int fscrypt_ioctl_remove_key(struct file *filp, void __user *_uarg)
down_write(&key->sem);
- /* If relevant, remove current user's claim to the key */
+ /* If relevant, remove current user's (or all users) claim to the key */
if (mk->mk_users && mk->mk_users->keys.nr_leaves_on_tree != 0) {
- err = remove_master_key_user(mk);
+ if (all_users)
+ err = keyring_clear(mk->mk_users);
+ else
+ err = remove_master_key_user(mk);
if (err) {
up_write(&key->sem);
goto out_put_key;
@@ -809,8 +815,21 @@ out_put_key:
err = put_user(status_flags, &uarg->removal_status_flags);
return err;
}
+
+int fscrypt_ioctl_remove_key(struct file *filp, void __user *uarg)
+{
+ return do_remove_key(filp, uarg, false);
+}
EXPORT_SYMBOL_GPL(fscrypt_ioctl_remove_key);
+int fscrypt_ioctl_remove_key_all_users(struct file *filp, void __user *uarg)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+ return do_remove_key(filp, uarg, true);
+}
+EXPORT_SYMBOL_GPL(fscrypt_ioctl_remove_key_all_users);
+
/*
* Retrieve the status of an fscrypt master encryption key.
*
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 8b8ff0484042..f622f7460ed8 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -143,6 +143,8 @@ extern int fscrypt_inherit_context(struct inode *, struct inode *,
extern void fscrypt_sb_free(struct super_block *sb);
extern int fscrypt_ioctl_add_key(struct file *filp, void __user *arg);
extern int fscrypt_ioctl_remove_key(struct file *filp, void __user *arg);
+extern int fscrypt_ioctl_remove_key_all_users(struct file *filp,
+ void __user *arg);
extern int fscrypt_ioctl_get_key_status(struct file *filp, void __user *arg);
/* keysetup.c */
@@ -396,6 +398,12 @@ static inline int fscrypt_ioctl_remove_key(struct file *filp, void __user *arg)
return -EOPNOTSUPP;
}
+static inline int fscrypt_ioctl_remove_key_all_users(struct file *filp,
+ void __user *arg)
+{
+ return -EOPNOTSUPP;
+}
+
static inline int fscrypt_ioctl_get_key_status(struct file *filp,
void __user *arg)
{
diff --git a/include/uapi/linux/fscrypt.h b/include/uapi/linux/fscrypt.h
index b9fb775e3db8..39ccfe9311c3 100644
--- a/include/uapi/linux/fscrypt.h
+++ b/include/uapi/linux/fscrypt.h
@@ -148,6 +148,7 @@ struct fscrypt_get_key_status_arg {
#define FS_IOC_GET_ENCRYPTION_POLICY_EX _IOWR('f', 22, __u8[9]) /* size + version */
#define FS_IOC_ADD_ENCRYPTION_KEY _IOWR('f', 23, struct fscrypt_add_key_arg)
#define FS_IOC_REMOVE_ENCRYPTION_KEY _IOWR('f', 24, struct fscrypt_remove_key_arg)
+#define FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS _IOWR('f', 25, struct fscrypt_remove_key_arg)
#define FS_IOC_GET_ENCRYPTION_KEY_STATUS _IOWR('f', 26, struct fscrypt_get_key_status_arg)
/**********************************************************************/