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.
Affected products
linux: linux kernel
References6
- git.kernel.org/stable/c/14b22be1dd844383eb03af9b1ee3b6b25d32aeaf Patch
- git.kernel.org/stable/c/259af6857a1b4f1e9ef8b780353f9d11c26a22bd Patch
- git.kernel.org/stable/c/a7449edf96143f192606ec8647e3167e1ecbd728 Patch
- git.kernel.org/stable/c/d2a675f2e238ec96c8e91e2718c1f910c9c8fb21 Patch
- git.kernel.org/stable/c/dfd05a16b5c9d1d98b47905f37f2fccda52173d1 Patch
- git.kernel.org/stable/c/c2d59527cba6d59f0d77a75c1101ab4e69758bea
Metrics
- CVSS 3.1
-
7.0
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 3 · as of 15 November 2026
- CWE
- CWE-415
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