| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49436: powerpc/papr_scm: Fix leaking nvdimm_events_map elements |
| |
| Description |
| =========== |
| |
| 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. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49436 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.18 with commit 4c08d4bbc089a95f3f38389c2b79dbc6ab24f10b and fixed in 5.18.3 with commit b073096df4dec70d0436321b7093bad27ae91f9e |
| Issue introduced in 5.18 with commit 4c08d4bbc089a95f3f38389c2b79dbc6ab24f10b and fixed in 5.19 with commit 0e0946e22f3665d27325d389ff45ade6e93f3678 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2022-49436 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| arch/powerpc/platforms/pseries/papr_scm.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/b073096df4dec70d0436321b7093bad27ae91f9e |
| https://git.kernel.org/stable/c/0e0946e22f3665d27325d389ff45ade6e93f3678 |
