diff options
Diffstat (limited to 'fs/btrfs/volumes.c')
| -rw-r--r-- | fs/btrfs/volumes.c | 38 |
1 files changed, 37 insertions, 1 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 8c7e74499ed1..9779ab410f8f 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -671,6 +671,42 @@ u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb) return has_metadata_uuid ? sb->metadata_uuid : sb->fsid; } +static bool is_same_device(struct btrfs_device *device, const char *new_path) +{ + struct path old = { .mnt = NULL, .dentry = NULL }; + struct path new = { .mnt = NULL, .dentry = NULL }; + char *old_path = NULL; + bool is_same = false; + int ret; + + if (!device->name) + goto out; + + old_path = kzalloc(PATH_MAX, GFP_NOFS); + if (!old_path) + goto out; + + rcu_read_lock(); + ret = strscpy(old_path, rcu_str_deref(device->name), PATH_MAX); + rcu_read_unlock(); + if (ret < 0) + goto out; + + ret = kern_path(old_path, LOOKUP_FOLLOW, &old); + if (ret) + goto out; + ret = kern_path(new_path, LOOKUP_FOLLOW, &new); + if (ret) + goto out; + if (path_equal(&old, &new)) + is_same = true; +out: + kfree(old_path); + path_put(&old); + path_put(&new); + return is_same; +} + /* * Handle scanned device having its CHANGING_FSID_V2 flag set and the fs_devices * being created with a disk that has already completed its fsid change. Such @@ -889,7 +925,7 @@ static noinline struct btrfs_device *device_list_add(const char *path, disk_super->fsid, devid, found_transid, path, current->comm, task_pid_nr(current)); - } else if (!device->name || strcmp(device->name->str, path)) { + } else if (!device->name || !is_same_device(device, path)) { /* * When FS is already mounted. * 1. If you are here and if the device->name is NULL that |