On Mon, May 13, 2019 at 01:39:12PM +1000, Tobin C. Harding wrote: > A failed call to kobject_init_and_add() must be followed by a call to > kobject_put(). Currently in the error path when adding fs_devices we > are missing this call. This could be fixed by calling > btrfs_sysfs_remove_fsid() if btrfs_sysfs_add_fsid() returns an error or > by adding a call to kobject_put() directly in btrfs_sysfs_add_fsid(). > Here we choose the second option because it prevents the slightly > unusual error path handling requirements of kobject from leaking out > into btrfs functions. > > Add a call to kobject_put() in the error path of kobject_add_and_init(). > This causes the release method to be called if kobject_init_and_add() > fails. open_tree() is the function that calls btrfs_sysfs_add_fsid() > and the error code in this function is already written with the > assumption that the release method is called during the error path of > open_tree() (as seen by the call to btrfs_sysfs_remove_fsid() under the > fail_fsdev_sysfs label). > > Signed-off-by: Tobin C. Harding <[email protected]> > --- > fs/btrfs/sysfs.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c > index 5a5930e3d32b..2f078b77fe14 100644 > --- a/fs/btrfs/sysfs.c > +++ b/fs/btrfs/sysfs.c > @@ -825,7 +825,12 @@ int btrfs_sysfs_add_fsid(struct btrfs_fs_devices > *fs_devs, > fs_devs->fsid_kobj.kset = btrfs_kset; > error = kobject_init_and_add(&fs_devs->fsid_kobj, > &btrfs_ktype, parent, "%pU", fs_devs->fsid); > - return error; > + if (error) { > + kobject_put(&fs_devs->fsid_kobj); > + return error; > + } > + > + return 0; > } > > int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
Reviewed-by: Greg Kroah-Hartman <[email protected]>
