| 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-2024-26738: powerpc/pseries/iommu: DLPAR add doesn't completely initialize pci_controller |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| powerpc/pseries/iommu: DLPAR add doesn't completely initialize pci_controller |
| |
| When a PCI device is dynamically added, the kernel oopses with a NULL |
| pointer dereference: |
| |
| BUG: Kernel NULL pointer dereference on read at 0x00000030 |
| Faulting instruction address: 0xc0000000006bbe5c |
| Oops: Kernel access of bad area, sig: 11 [#1] |
| LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries |
| Modules linked in: rpadlpar_io rpaphp rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs xsk_diag bonding nft_compat nf_tables nfnetlink rfkill binfmt_misc dm_multipath rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_core_mod ib_umad ib_iser libiscsi scsi_transport_iscsi ib_ipoib rdma_cm iw_cm ib_cm mlx5_ib ib_uverbs ib_core pseries_rng drm drm_panel_orientation_quirks xfs libcrc32c mlx5_core mlxfw sd_mod t10_pi sg tls ibmvscsi ibmveth scsi_transport_srp vmx_crypto pseries_wdt psample dm_mirror dm_region_hash dm_log dm_mod fuse |
| CPU: 17 PID: 2685 Comm: drmgr Not tainted 6.7.0-203405+ #66 |
| Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries |
| NIP: c0000000006bbe5c LR: c000000000a13e68 CTR: c0000000000579f8 |
| REGS: c00000009924f240 TRAP: 0300 Not tainted (6.7.0-203405+) |
| MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 24002220 XER: 20040006 |
| CFAR: c000000000a13e64 DAR: 0000000000000030 DSISR: 40000000 IRQMASK: 0 |
| ... |
| NIP sysfs_add_link_to_group+0x34/0x94 |
| LR iommu_device_link+0x5c/0x118 |
| Call Trace: |
| iommu_init_device+0x26c/0x318 (unreliable) |
| iommu_device_link+0x5c/0x118 |
| iommu_init_device+0xa8/0x318 |
| iommu_probe_device+0xc0/0x134 |
| iommu_bus_notifier+0x44/0x104 |
| notifier_call_chain+0xb8/0x19c |
| blocking_notifier_call_chain+0x64/0x98 |
| bus_notify+0x50/0x7c |
| device_add+0x640/0x918 |
| pci_device_add+0x23c/0x298 |
| of_create_pci_dev+0x400/0x884 |
| of_scan_pci_dev+0x124/0x1b0 |
| __of_scan_bus+0x78/0x18c |
| pcibios_scan_phb+0x2a4/0x3b0 |
| init_phb_dynamic+0xb8/0x110 |
| dlpar_add_slot+0x170/0x3b8 [rpadlpar_io] |
| add_slot_store.part.0+0xb4/0x130 [rpadlpar_io] |
| kobj_attr_store+0x2c/0x48 |
| sysfs_kf_write+0x64/0x78 |
| kernfs_fop_write_iter+0x1b0/0x290 |
| vfs_write+0x350/0x4a0 |
| ksys_write+0x84/0x140 |
| system_call_exception+0x124/0x330 |
| system_call_vectored_common+0x15c/0x2ec |
| |
| Commit a940904443e4 ("powerpc/iommu: Add iommu_ops to report capabilities |
| and allow blocking domains") broke DLPAR add of PCI devices. |
| |
| The above added iommu_device structure to pci_controller. During |
| system boot, PCI devices are discovered and this newly added iommu_device |
| structure is initialized by a call to iommu_device_register(). |
| |
| During DLPAR add of a PCI device, a new pci_controller structure is |
| allocated but there are no calls made to iommu_device_register() |
| interface. |
| |
| Fix is to register the iommu device during DLPAR add as well. |
| |
| The Linux kernel CVE team has assigned CVE-2024-26738 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.4 with commit a940904443e432623579245babe63e2486ff327b and fixed in 6.6.19 with commit b8315b2e25b4e68e42fcb74630f824b9a5067765 |
| Issue introduced in 6.4 with commit a940904443e432623579245babe63e2486ff327b and fixed in 6.7.7 with commit 46e36ebd5e00a148b67ed77c1d31675996f77c25 |
| Issue introduced in 6.4 with commit a940904443e432623579245babe63e2486ff327b and fixed in 6.8 with commit a5c57fd2e9bd1c8ea8613a8f94fd0be5eccbf321 |
| |
| 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-2024-26738 |
| 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/include/asm/ppc-pci.h |
| arch/powerpc/kernel/iommu.c |
| arch/powerpc/platforms/pseries/pci_dlpar.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/b8315b2e25b4e68e42fcb74630f824b9a5067765 |
| https://git.kernel.org/stable/c/46e36ebd5e00a148b67ed77c1d31675996f77c25 |
| https://git.kernel.org/stable/c/a5c57fd2e9bd1c8ea8613a8f94fd0be5eccbf321 |
