File 0003-btrfs-progs-inspect-use-find_mount_fsroot-in-logical.patch of Package btrfsprogs.23274
From 4229af99a351c5fa0fe7ed4170258c6ac9db0562 Mon Sep 17 00:00:00 2001
From: Marcos Paulo de Souza <mpdesouza@suse.com>
Date: Wed, 13 Jan 2021 13:55:31 -0300
Subject: [PATCH 3/4] btrfs-progs: inspect: use find_mount_fsroot in
logical-resolve
By using find_mount_fsroot we ensure that we return a valid path to the
final user, by ensuring that even if we return a bind mount, the
pathname of btrfs used was the same from the original mount.
This for a case when bind mounts and normal mount -o subvol=/path are
mixed.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
cmds-inspect.c | 45 ++++++++++++++++++++++++++++++++++++---------
1 file changed, 36 insertions(+), 9 deletions(-)
--- a/cmds-inspect.c
+++ b/cmds-inspect.c
@@ -234,6 +234,7 @@ static int cmd_inspect_logical_resolve(i
DIR *dirs = NULL;
if (getpath) {
+ char mount_path[PATH_MAX];
name = btrfs_list_path_for_root(fd, root);
if (IS_ERR(name)) {
ret = PTR_ERR(name);
@@ -242,24 +243,50 @@ static int cmd_inspect_logical_resolve(i
if (!name) {
path_ptr[-1] = '\0';
path_fd = fd;
+ strncpy(mount_path, full_path, PATH_MAX);
} else {
- path_ptr[-1] = '/';
- ret = snprintf(path_ptr, bytes_left, "%s",
- name);
- free(name);
- if (ret >= bytes_left) {
- error("path buffer too small: %d bytes",
- bytes_left - ret);
+ char *mounted = NULL;
+ char subvol[PATH_MAX];
+ char subvolid[PATH_MAX];
+
+ /*
+ * btrfs_list_path_for_root returns the full
+ * path to the subvolume pointed by root, but the
+ * subvolume can be mounted in a directory name
+ * different from the subvolume name. In this
+ * case we need to find the correct mount point
+ * using same subvolume path and subvol id found
+ * before.
+ */
+
+ snprintf(subvol, PATH_MAX, "/%s", name);
+ snprintf(subvolid, PATH_MAX, "%llu", root);
+
+ ret = find_mount_fsroot(subvol, subvolid, &mounted);
+
+ if (ret) {
+ error("failed to parse mountinfo");
goto out;
}
- path_fd = btrfs_open_dir(full_path, &dirs, 1);
+
+ if (!mounted) {
+ printf(
+ "inode %llu subvol %s could not be accessed: not mounted\n",
+ inum, name);
+ continue;
+ }
+
+ strncpy(mount_path, mounted, PATH_MAX);
+ free(mounted);
+
+ path_fd = btrfs_open_dir(mount_path, &dirs, 1);
if (path_fd < 0) {
ret = -ENOENT;
goto out;
}
}
ret = __ino_to_path_fd(inum, path_fd, verbose,
- full_path);
+ mount_path);
if (path_fd != fd)
close_file_or_dir(path_fd, dirs);
} else {
