Bug 2396500 (CVE-2023-53421)
| Summary: | CVE-2023-53421 kernel: blk-cgroup: Reinit blkg_iostat_set after clearing in blkcg_reset_stats() | ||
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| Product: | [Other] Security Response | Reporter: | OSIDB Bzimport <bzimport> |
| Component: | vulnerability | Assignee: | Product Security DevOps Team <prodsec-dev> |
| Status: | NEW --- | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | unspecified | Keywords: | Security |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | --- | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | Type: | --- | |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Reinit blkg_iostat_set after clearing in blkcg_reset_stats() When blkg_alloc() is called to allocate a blkcg_gq structure with the associated blkg_iostat_set's, there are 2 fields within blkg_iostat_set that requires proper initialization - blkg & sync. The former field was introduced by commit 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()") while the later one was introduced by commit f73316482977 ("blk-cgroup: reimplement basic IO stats using cgroup rstat"). Unfortunately those fields in the blkg_iostat_set's are not properly re-initialized when they are cleared in v1's blkcg_reset_stats(). This can lead to a kernel panic due to NULL pointer access of the blkg pointer. The missing initialization of sync is less problematic and can be a problem in a debug kernel due to missing lockdep initialization. Fix these problems by re-initializing them after memory clearing.