btrfs: fix double free in create_space_info_sub_group() error path
En bref
Sévérité
HIGH 7.0
EPSS
EPSS 0.14 % · centile 3 (2026-10-27)
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
Linux
Statut NVD
Modified
Description
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix double free in create_space_info_sub_group() error path
When kobject_init_and_add() fails, the call chain is:
create_space_info_sub_group()
-> btrfs_sysfs_add_space_info_type()
-> kobject_init_and_add()
-> failure
-> kobject_put(&sub_group->kobj)
-> space_info_release()
-> kfree(sub_group)
Then control returns to create_space_info_sub_group(), where:
btrfs_sysfs_add_space_info_type() returns error
-> kfree(sub_group)
Thus, sub_group is freed twice.
Keep parent->sub_group[index] = NULL for the failure path, but after
btrfs_sysfs_add_space_info_type() has called kobject_put(), let the
kobject release callback handle the cleanup.
