Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix leaks and online flag on radix_tree_insert failure When radix_tree_insert() fails in blkg_create(), the error path has two issues: 1. blkg->online is set to true unconditionally, even when the blkg was never fully inserted. Move the assignment inside the success block. 2. The error path calls blkg_put() without first calling percpu_ref_kill(). Because the refcount is still in percpu mode, percpu_ref_put() only does this_cpu_sub() without checking for zero, so blkg_release() is never triggered. This permanently leaks the blkg memory, its percpu iostat, policy data, the parent blkg reference, and the cgroup css reference — the latter preventing the cgroup from ever being destroyed. Fix by replacing blkg_put() with percpu_ref_kill(), matching the pattern used in blkg_destroy().
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 7fcf2b033b84e261dca283bc2911aaea4b07b525 before 0f840db042caee9d2f3dcdcf97d6674f6e4c1e30; affected 7fcf2b033b84e261dca283bc2911aaea4b07b525 before f53945d7c712efe63fadbcc5ffed6370871fd0d3; affected 7fcf2b033b84e261dca283bc2911aaea4b07b525 before ada8270ccdb6f212da5eb22614c28ea418746a4a; affected 7fcf2b033b84e261dca283bc2911aaea4b07b525 before c3650be82ef6e7af13b79b2d10a7363bdf54aa7f; affected 7fcf2b033b84e261dca283bc2911aaea4b07b525 before 6e85f02d45b5977c0326a8d854c6db878aa6b34a; affected 7fcf2b033b84e261dca283bc2911aaea4b07b525 before 4c0d150fb98ea40760611979f4e664c244b20966; affected 7fcf2b033b84e261dca283bc2911aaea4b07b525 before dbbca20764382b4d411ec2918f4e278ffe547acc |
| Linux / Linux | affected 5.0; unaffected 0 before 5.0; unaffected 5.10.271 through 5.10.*; unaffected 5.15.222 through 5.15.*; unaffected 6.1.189 through 6.1.*; unaffected 6.6.158 through 6.6.*; unaffected 6.12.111 through 6.12.*; unaffected 6.18.53 through 6.18.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/0f840db042caee9d2f3dcdcf97d6674f6e4c1e30
- https://git.kernel.org/stable/c/f53945d7c712efe63fadbcc5ffed6370871fd0d3
- https://git.kernel.org/stable/c/ada8270ccdb6f212da5eb22614c28ea418746a4a
- https://git.kernel.org/stable/c/c3650be82ef6e7af13b79b2d10a7363bdf54aa7f
- https://git.kernel.org/stable/c/6e85f02d45b5977c0326a8d854c6db878aa6b34a
- https://git.kernel.org/stable/c/4c0d150fb98ea40760611979f4e664c244b20966
- https://git.kernel.org/stable/c/dbbca20764382b4d411ec2918f4e278ffe547acc