| From bippy-1.1.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49894: cxl/region: Fix region HPA ordering validation |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| cxl/region: Fix region HPA ordering validation |
| |
| Some regions may not have any address space allocated. Skip them when |
| validating HPA order otherwise a crash like the following may result: |
| |
| devm_cxl_add_region: cxl_acpi cxl_acpi.0: decoder3.4: created region9 |
| BUG: kernel NULL pointer dereference, address: 0000000000000000 |
| [..] |
| RIP: 0010:store_targetN+0x655/0x1740 [cxl_core] |
| [..] |
| Call Trace: |
| <TASK> |
| kernfs_fop_write_iter+0x144/0x200 |
| vfs_write+0x24a/0x4d0 |
| ksys_write+0x69/0xf0 |
| do_syscall_64+0x3a/0x90 |
| |
| store_targetN+0x655/0x1740: |
| alloc_region_ref at drivers/cxl/core/region.c:676 |
| (inlined by) cxl_port_attach_region at drivers/cxl/core/region.c:850 |
| (inlined by) cxl_region_attach at drivers/cxl/core/region.c:1290 |
| (inlined by) attach_target at drivers/cxl/core/region.c:1410 |
| (inlined by) store_targetN at drivers/cxl/core/region.c:1453 |
| |
| The Linux kernel CVE team has assigned CVE-2022-49894 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.0 with commit 384e624bb211b406db40edc900bb51af8bb267d0 and fixed in 6.0.8 with commit 12316b9f7c18138ae656050cfd716728e27b7e2f |
| Issue introduced in 6.0 with commit 384e624bb211b406db40edc900bb51af8bb267d0 and fixed in 6.1 with commit a90accb358ae33ea982a35595573f7a045993f8b |
| |
| 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-2022-49894 |
| 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: |
| drivers/cxl/core/region.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/12316b9f7c18138ae656050cfd716728e27b7e2f |
| https://git.kernel.org/stable/c/a90accb358ae33ea982a35595573f7a045993f8b |
