From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E866C3BCD0B for ; Tue, 6 Oct 2026 08:48:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791276490; cv=none; b=bNKAekYEpFHYL6mmfVEHdC/yN0H3p5X8v9e3+/J87PTVS5C/H55Ya90uFJjjjvJ3CCWROT8s1EIBfTXcY4Y1pWHJnjg6XH2DLhwkhS9UtK4axTdm446EZ34bnCd6NxnqEYOpV6pNAujRpdn1gRTsiFQo2HxkOJRpZx3u3HLHer4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791276490; c=relaxed/simple; bh=3QkWBPK4a/KNiV9NKuR40Dda9ohZVr4YyuJXtWeqEHc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=uU/iaifgAtPMbN9IhId/cJ3qDvkDRMruy4xCTA+IxuP0ICdWK6FqzXCEcYjMJjEESLeuOw/v7C3h3Pdew+VKHUk/naaIe9Y98VPGFlf81rIVLUPNHuSVintJcxXIjyXcLQadH8X8uIVC07FicXnwSBjkLSrcXY7FpXCDJvA07Dg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=W29ZzVaY; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="W29ZzVaY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D33D71F000FF; Tue, 6 Oct 2026 08:48:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791276488; bh=asi6WLP9C1VldhVjGcKs/pn5u9B9IkoBtAKviOOxudI=; h=From:To:Cc:Subject:Date:Reply-To; b=W29ZzVaYZNkiVmhUiySPYqGS++rI1wMA2QsUaQct6SFB2qFIWPEY8Jxl4GpK6kpb4 7Pny+icTydDTZwpzZzq5AcCU35RZKAS5KGc9Bw6BSUntKcNyey/PFJ6fYvleg9J50N q4AQsj2cdgZ52xnsSUP0QKHyoRZAHYMXg2hu6oL0= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-98216: IB/hfi1: Fix the PIO_CRED credit-return mmap Date: Tue, 6 Oct 2026 10:45:17 +0200 Message-ID: <2026100640-CVE-2026-98216-e3b4@gregkh> X-Mailer: git-send-email 2.56.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=4941; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=9ZbBbyWQ1nWsDjGGeaG8J/xw6eKovw9SKl5Br9XYyZs=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlHtvy4rjmX0fb9mWWxx4oqCtbb6NkEScn+ueex+UaW9 zab3R1FHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjCREh2GBauZ1t3OPx++RPZp 2No5pfudLp95X8wwz+CQ+eI+5hvan9SUpmYF9jVUSZ7VBwA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: IB/hfi1: Fix the PIO_CRED credit-return mmap hfi1_file_mmap()'s PIO_CRED case must hand user space the single credit-return page that holds this context's entry. That page is the second or third page of the per-node credit-return allocation once the hardware send context index reaches 64 or 128, so the failure below is intermittent: when the entry lands on the first page the offset is zero and everything works. Two things are wrong. First, cr_page_offset is a byte offset but .va is a struct credit_return *, so adding it is pointer arithmetic and scales the offset by sizeof(struct credit_return) == 64. memvirt then lands 256 KiB or 512 KiB past a 10240-byte allocation. With an IOMMU translating, that address is inside the vmalloc range but in no vm_area, so dma_mmap_coherent() -> iommu_dma_mmap() finds no pages, vmalloc_to_pfn() returns page_to_pfn(NULL), and remap_pfn_range() installs a frame above MAXPHYADDR. The first user read then takes: psm2_ep_open_pr: Corrupted page table at address 7a14d007e000 PGD 800000013886a067 P4D 800000013886a067 PUD 13886b067 PMD 13886c067 PTE 800049168e911235 Oops: Bad pagetable: 000d [#1] SMP PTI Second, and still wrong once the arithmetic is corrected, dma_mmap_coherent() describes a whole coherent buffer and selects the page within it with vma->vm_pgoff. Offsetting cpu_addr has no effect: for a vmap'd allocation iommu_dma_mmap() uses cpu_addr only to locate the vm_area and then maps pages[vm_pgoff], which hfi1_file_mmap() has just set to 0. User space therefore always receives the first credit-return page, every credit read is for the wrong context, and send PIO stalls forever. Use the DMA API as intended: pass the base of the allocation with its full length and select the page with vm_pgoff. A separate length is needed because memlen must keep describing the VMA for the existing size check. The dma-direct path stays correct as well, since dma_direct_mmap() adds the same vm_pgoff to the base pfn. Tested on a Dell T7610 (Xeon E5-2650 v2, Intel IOMMU in DMA-FQ mode) against a Threadripper PRO 3995WX peer, both Omni-Path 100. Before this change psm2_ep_open() Oopses the kernel; with only the arithmetic corrected psm2_ep_open() succeeds but any transfer that uses send PIO hangs, PSM2_SDMA=2 (send PIO disabled) completing normally while PSM2_SDMA=0 (send PIO only) hangs every time. With this change send PIO, send DMA and the default mixed mode all work. The Linux kernel CVE team has assigned CVE-2026-98216 to this issue. Affected and fixed versions =========================== Issue introduced in 6.3 with commit 1ec82317a1daac78c04b0c15af89018ccf9fa2b7 and fixed in 6.6.158 with commit 535530bb2ea5254e1e9f55280143d262dd065204 Issue introduced in 6.3 with commit 1ec82317a1daac78c04b0c15af89018ccf9fa2b7 and fixed in 6.12.112 with commit dcebe0b0bb080a25fe08011fd6b6e741f7912f01 Issue introduced in 6.3 with commit 1ec82317a1daac78c04b0c15af89018ccf9fa2b7 and fixed in 6.18.54 with commit 180752deb7270ad37394ab6ef7cf4978fad040b3 Issue introduced in 6.3 with commit 1ec82317a1daac78c04b0c15af89018ccf9fa2b7 and fixed in 7.2.8 with commit bafeac9ce5d1ce5256bcf7e5702e831e9aaf419b Issue introduced in 6.3 with commit 1ec82317a1daac78c04b0c15af89018ccf9fa2b7 and fixed in 7.3-rc4 with commit 62f0f34fbd2b2d5653d33d3b9d42fdcabb1c0101 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-2026-98216 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/infiniband/hw/hfi1/file_ops.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/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