{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98216","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-25T10:25:14.326Z","datePublished":"2026-10-06T08:44:52.288Z","dateUpdated":"2026-10-07T06:49:30.564Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-10-07T06:49:30.564Z"},"descriptions":[{"lang":"en","value":"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."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The bad mapping is created by hfi1_file_mmap() PIO_CRED case, reached by a local process via open() of the /dev/hfi1_N user cdev, the ASSIGN_CTXT ioctl and mmap() of the PIO_CRED token; no remote peer supplies any data to this path.\nAC:L - With IOMMU DMA translation (common on x86 servers), the pointer-scaled cr_page_offset deterministically sends memvirt 256/512 KiB past the credit-return buffer for send context index >=64, and the attacker can raise the index by opening more contexts; the commit's reproducer oopses every time.\nPR:L - hfi1_user_devnode() creates the user device node with mode 0666 and hfi1_file_open() has no capability check, so any unprivileged local user on an Omni-Path node (e.g. a shared HPC node) can assign a context and issue the mmap.\nUI:N - The attacker triggers the faulty mapping and the faulting read entirely from their own process; no other user or administrator has to do anything.\nS:U - Both impacts stay within the host kernel's own authority: a kernel page or bogus PFN is mapped into a local process and the kernel oopses; no VM, IOMMU or sandbox boundary is crossed.\nC:H - If the out-of-range vmalloc address lands in a non-DMA-coherent vm_area, iommu_dma_mmap() falls back to vmalloc_to_pfn() and remap_pfn_range() exposes that kernel page to userspace read-only with no reference held, so the user can read unrelated kernel memory, even after it is freed and reused.\nI:N - The PIO_CRED VMA is read-only: VM_WRITE is rejected with -EPERM and VM_MAYWRITE is cleared, so the mis-mapped page cannot be written from userspace, and the bug gives no kernel write primitive.\nA:H - When the address falls in a vmalloc hole, page_to_pfn(NULL) installs a PTE for a frame above MAXPHYADDR and the first user read causes an 'Oops: Bad pagetable' kernel crash; even with the arithmetic fixed, mapping the wrong page leaves send PIO hung forever."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/hfi1/file_ops.c"],"versions":[{"version":"1ec82317a1daac78c04b0c15af89018ccf9fa2b7","lessThan":"535530bb2ea5254e1e9f55280143d262dd065204","status":"affected","versionType":"git"},{"version":"1ec82317a1daac78c04b0c15af89018ccf9fa2b7","lessThan":"dcebe0b0bb080a25fe08011fd6b6e741f7912f01","status":"affected","versionType":"git"},{"version":"1ec82317a1daac78c04b0c15af89018ccf9fa2b7","lessThan":"180752deb7270ad37394ab6ef7cf4978fad040b3","status":"affected","versionType":"git"},{"version":"1ec82317a1daac78c04b0c15af89018ccf9fa2b7","lessThan":"bafeac9ce5d1ce5256bcf7e5702e831e9aaf419b","status":"affected","versionType":"git"},{"version":"1ec82317a1daac78c04b0c15af89018ccf9fa2b7","lessThan":"62f0f34fbd2b2d5653d33d3b9d42fdcabb1c0101","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/hfi1/file_ops.c"],"versions":[{"version":"6.3","status":"affected"},{"version":"0","lessThan":"6.3","status":"unaffected","versionType":"semver"},{"version":"6.6.158","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.54","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.8","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc4","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"6.6.158"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"6.12.112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"6.18.54"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"7.2.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"7.3-rc4"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/535530bb2ea5254e1e9f55280143d262dd065204"},{"url":"https://git.kernel.org/stable/c/dcebe0b0bb080a25fe08011fd6b6e741f7912f01"},{"url":"https://git.kernel.org/stable/c/180752deb7270ad37394ab6ef7cf4978fad040b3"},{"url":"https://git.kernel.org/stable/c/bafeac9ce5d1ce5256bcf7e5702e831e9aaf419b"},{"url":"https://git.kernel.org/stable/c/62f0f34fbd2b2d5653d33d3b9d42fdcabb1c0101"}],"title":"IB/hfi1: Fix the PIO_CRED credit-return mmap","x_generator":{"engine":"bippy-1.2.0"}}}}