{"id":"CVE-2026-98216","revision":"f362d5f4efcd4986a34b24e5f21038c7","records":[{"revision":"f362d5f4efcd4986a34b24e5f21038c7","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98216","aliases":[],"title":"IB/hfi1: Fix the PIO_CRED credit-return mmap","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nIB/hfi1: Fix the PIO_CRED credit-return mmap\n\nhfi1_file_mmap()'s PIO_CRED case must hand user space the single\ncredit-return page that holds this context's entry.  That page is the\nsecond or third page of the per-node credit-return allocation once the\nhardware send context index reaches 64 or 128, so the failure below is\nintermittent: when the entry lands on the first page the offset is zero\nand everything works.\n\nTwo things are wrong.\n\nFirst, cr_page_offset is a byte offset but .va is a struct\ncredit_return *, so adding it is pointer arithmetic and scales the offset\nby sizeof(struct credit_return) == 64.  memvirt then lands 256 KiB or\n512 KiB past a 10240-byte allocation.  With an IOMMU translating, that\naddress is inside the vmalloc range but in no vm_area, so\ndma_mmap_coherent() -> iommu_dma_mmap() finds no pages, vmalloc_to_pfn()\nreturns page_to_pfn(NULL), and remap_pfn_range() installs a frame above\nMAXPHYADDR.  The first user read then takes:\n\n  psm2_ep_open_pr: Corrupted page table at address 7a14d007e000\n  PGD 800000013886a067 P4D 800000013886a067 PUD 13886b067 PMD 13886c067\n                                            PTE 800049168e911235\n  Oops: Bad pagetable: 000d [#1] SMP PTI\n\nSecond, and still wrong once the arithmetic is corrected,\ndma_mmap_coherent() describes a whole coherent buffer and selects the\npage within it with vma->vm_pgoff.  Offsetting cpu_addr has no effect:\nfor a vmap'd allocation iommu_dma_mmap() uses cpu_addr only to locate the\nvm_area and then maps pages[vm_pgoff], which hfi1_file_mmap() has just\nset to 0.  User space therefore always receives the first credit-return\npage, every credit read is for the wrong context, and send PIO stalls\nforever.\n\nUse the DMA API as intended: pass the base of the allocation with its\nfull length and select the page with vm_pgoff.  A separate length is\nneeded because memlen must keep describing the VMA for the existing size\ncheck.  The dma-direct path stays correct as well, since dma_direct_mmap()\nadds the same vm_pgoff to the base pfn.\n\nTested on a Dell T7610 (Xeon E5-2650 v2, Intel IOMMU in DMA-FQ mode)\nagainst a Threadripper PRO 3995WX peer, both Omni-Path 100.  Before this\nchange psm2_ep_open() Oopses the kernel; with only the arithmetic\ncorrected psm2_ep_open() succeeds but any transfer that uses send PIO\nhangs, PSM2_SDMA=2 (send PIO disabled) completing normally while\nPSM2_SDMA=0 (send PIO only) hangs every time.  With this change send PIO,\nsend DMA and the default mixed mode all work.","state":0,"publishedAt":"2026-10-06T08:44:52.288+00:00","modifiedAt":"2026-10-19T09:15:47.022+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/infiniband/hw/hfi1/file_ops.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"1ec82317a1daac78c04b0c15af89018ccf9fa2b7\",\n                            \"lessThan\": \"535530bb2ea5254e1e9f55280143d262dd065204\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1ec82317a1daac78c04b0c15af89018ccf9fa2b7\",\n                            \"lessThan\": \"dcebe0b0bb080a25fe08011fd6b6e741f7912f01\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1ec82317a1daac78c04b0c15af89018ccf9fa2b7\",\n                            \"lessThan\": \"180752deb7270ad37394ab6ef7cf4978fad040b3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1ec82317a1daac78c04b0c15af89018ccf9fa2b7\",\n                            \"lessThan\": \"bafeac9ce5d1ce5256bcf7e5702e831e9aaf419b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1ec82317a1daac78c04b0c15af89018ccf9fa2b7\",\n                            \"lessThan\": \"62f0f34fbd2b2d5653d33d3b9d42fdcabb1c0101\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/infiniband/hw/hfi1/file_ops.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.3\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.3\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.158\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.112\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.54\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.8\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":7.1,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/535530bb2ea5254e1e9f55280143d262dd065204","https://git.kernel.org/stable/c/dcebe0b0bb080a25fe08011fd6b6e741f7912f01","https://git.kernel.org/stable/c/180752deb7270ad37394ab6ef7cf4978fad040b3","https://git.kernel.org/stable/c/bafeac9ce5d1ce5256bcf7e5702e831e9aaf419b","https://git.kernel.org/stable/c/62f0f34fbd2b2d5653d33d3b9d42fdcabb1c0101"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98216","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98216","identifiers":["CVE-2026-98216"]},"retained":false,"historicalAffected":[]}],"coverage":[]}