CVE-2022-49436

Summary

In the Linux kernel, the following vulnerability has been resolved:

powerpc/papr_scm: Fix leaking nvdimm_events_map elements

Right now 'char *' elements allocated for individual 'stat_id' in 'papr_scm_priv.nvdimm_events_map[]' during papr_scm_pmu_check_events(), get leaked in papr_scm_remove() and papr_scm_pmu_register(), papr_scm_pmu_check_events() error paths.

Also individual 'stat_id' arent NULL terminated 'char *' instead they are fixed 8-byte sized identifiers. However papr_scm_pmu_register() assumes it to be a NULL terminated 'char *' and at other places it assumes it to be a 'papr_scm_perf_stat.stat_id' sized string which is 8-byes in size.

Fix this by allocating the memory for papr_scm_priv.nvdimm_events_map to also include space for 'stat_id' entries. This is possible since number of available events/stat_ids are known upfront. This saves some memory and one extra level of indirection from 'nvdimm_events_map' to 'stat_id'. Also rest of the code can continue to call 'kfree(papr_scm_priv.nvdimm_events_map)' without needing to iterate over the array and free up individual elements.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux4c08d4bbc089a95f3f38389c2b79dbc6ab24f10b < b073096df4dec70d0436321b7093bad27ae91f9eaffected
LinuxLinux4c08d4bbc089a95f3f38389c2b79dbc6ab24f10b < 0e0946e22f3665d27325d389ff45ade6e93f3678affected
LinuxLinux5.18affected
LinuxLinux0 < 5.18unaffected
LinuxLinux5.18.3 <= 5.18.*unaffected
LinuxLinux5.19 <= *unaffected

Weaknesses

References