{"id":"CVE-2026-98640","title":"HID: amd_sfh: Validate PCI BAR size before mapping","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: amd_sfh: Validate PCI BAR size before mapping\n\nThe amd_sfh driver maps PCI BAR 2 using pcim_iomap_regions() and\nsubsequently accesses MMIO registers at offsets up …","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 92bf2883da0306ab9d1eb794acd1058fc5088ebc","Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 7b3747d77767f066ccf4a9e8e3a8381643ab5368","Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 5ff24aa7af0bca0780fe4e6effce902065f2c0a7","Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < dc687489131559ee52f447592f6d039a5a013061","Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 5f9e2ecb725adced013fbf5f94b9f185fad2e7d9","Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < ee25833f037fa22d23ffdbfeebabe3579e8a0346","Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 65bcc5f89704efe5b9d69d4ea2c1002d90c31382","Linux 5.11"],"published":"2026-10-18","updated":"2026-10-18","sourceUpdated":"2026-10-18T15:20:11.777Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98640","references":[{"url":"https://git.kernel.org/stable/c/92bf2883da0306ab9d1eb794acd1058fc5088ebc"},{"url":"https://git.kernel.org/stable/c/7b3747d77767f066ccf4a9e8e3a8381643ab5368"},{"url":"https://git.kernel.org/stable/c/5ff24aa7af0bca0780fe4e6effce902065f2c0a7"},{"url":"https://git.kernel.org/stable/c/dc687489131559ee52f447592f6d039a5a013061"},{"url":"https://git.kernel.org/stable/c/5f9e2ecb725adced013fbf5f94b9f185fad2e7d9"},{"url":"https://git.kernel.org/stable/c/ee25833f037fa22d23ffdbfeebabe3579e8a0346"},{"url":"https://git.kernel.org/stable/c/65bcc5f89704efe5b9d69d4ea2c1002d90c31382"}],"tags":["cve.org"],"ingestedAt":"2026-10-18T15:45:12.232Z","slug":"CVE-2026-98640","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nHID: amd_sfh: Validate PCI BAR size before mapping\n\nThe amd_sfh driver maps PCI BAR 2 using pcim_iomap_regions() and\nsubsequently accesses MMIO registers at offsets up to 0x10958 (e.g.,\nAMD_P2C_MSG3 at 0x1068C). However, the driver never validates that the BAR\nsize is large enough to cover these accesses. If the driver is bound to a\ndevice with a smaller BAR 2, this leads to an out-of-bounds memory access\nand a page fault during the probe function.\n\nFor example, a page fault can occur when reading from privdata->mmio +\nAMD_P2C_MSG3 in mp2_select_ops():\n\n  BUG: unable to handle page fault for address: ffffc9000390368c\n  PGD 100000067 P4D 100000067 PUD 1012c1067 PMD 105b64067 PTE 0\n  Oops: Oops: 0000 [#1] SMP KASAN NOPTI\n  RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline]\n  RIP: 0010:mp2_select_ops drivers/hid/amd-sfh-hid/amd_sfh_pcie.c:282\n  [inline]\n  RIP: 0010:amd_mp2_pci_probe+0x337/0x5f0\n  drivers/hid/amd-sfh-hid/amd_sfh_pcie.c:487\n  Call Trace:\n   <TASK>\n   local_pci_probe drivers/pci/pci-driver.c:332 [inline]\n   pci_call_probe drivers/pci/pci-driver.c:394 [inline]\n   __pci_device_probe drivers/pci/pci-driver.c:455 [inline]\n   pci_device_probe+0x431/0xc90 drivers/pci/pci-driver.c:489\n\nFix this by verifying that the length of BAR 2 is at least 128KB before\nattempting to map it. Since the maximum accessed offset is 0x10958, and PCI\nBAR sizes are powers of 2, any legitimate hardware will have a BAR size of\nat least 128KB.\n\n## Affected\n\n- `Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 92bf2883da0306ab9d1eb794acd1058fc5088ebc`\n- `Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 7b3747d77767f066ccf4a9e8e3a8381643ab5368`\n- `Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 5ff24aa7af0bca0780fe4e6effce902065f2c0a7`\n- `Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < dc687489131559ee52f447592f6d039a5a013061`\n- `Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 5f9e2ecb725adced013fbf5f94b9f185fad2e7d9`\n- `Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < ee25833f037fa22d23ffdbfeebabe3579e8a0346`\n- `Linux >= 4f567b9f8141a86c7d878fadf136e5d1408e3e61 < 65bcc5f89704efe5b9d69d4ea2c1002d90c31382`\n- `Linux 5.11`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}