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CVE-2026-80917

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: PCI: host-generic: Fix NULL pointer dereference on 32-bit CAM systems On 32-bit systems the config space is too large to ioremap in one go, so pci_ecam_create() maps each bus segment separately and relies on the ->add_bus callback (pci_ecam_add_bus) to populate the per-bus mapping in cfg->winp[]. pci_ecam_map_bus() then uses that mapping as the base for every config access. The generic ECAM ops (pci_generic_ecam_ops) already provide the ->add_bus and ->remove_bus callbacks, but the CAM (legacy) ops in pci-host-generic.c do not. As a result, on a 32-bit host using "pci-host-cam-generic" the per-bus mapping is never set up and the first config read dereferences a NULL base, crashing during bus enumeration: Unable to handle kernel NULL pointer dereference at virtual address 00000800 Oops [#1] CPU: 0 PID: 1 Comm: swapper Not tainted 6.9.7+ #43 Hardware name: Digilent Nexys-Video-A7 RV32 (DT) epc : pci_generic_config_read+0x40/0xb0 ra : pci_generic_config_read+0x2c/0xb0 [<c038db9c>] pci_generic_config_read+0x40/0xb0 [<c038da04>] pci_bus_read_config_dword+0x50/0xb0 [<c0391e94>] pci_bus_generic_read_dev_vendor_id+0x3c/0x1ec [<c039245c>] pci_scan_single_device+0xa4/0x11c [<c0392570>] pci_scan_slot+0x9c/0x23c [<c039388c>] pci_scan_child_bus_extend+0x58/0x2f4 [<c0393db0>] pci_scan_root_bus_bridge+0x64/0xe8 [<c0393e54>] pci_host_probe+0x20/0xc8 [<c03bc6f4>] pci_host_common_probe+0x144/0x1e4 Fix this by giving the CAM ops the same ->add_bus/->remove_bus callbacks. Since pci_ecam_add_bus() and pci_ecam_remove_bus() are static to ecam.c, move the CAM ops definition there as pci_generic_cam_ops (mirroring pci_generic_ecam_ops) and export it for pci-host-generic.c to reference. [mani: removed timestamp from log]

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-09 17:17:46.680000
Last modified
2026-10-19 09:17:22.563000
View original CVE JSON
{
  "id": "CVE-2026-80917",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-09T17:17:46.680",
  "lastModified": "2026-10-19T09:17:22.563",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nPCI: host-generic: Fix NULL pointer dereference on 32-bit CAM systems\n\nOn 32-bit systems the config space is too large to ioremap in one go, so\npci_ecam_create() maps each bus segment separately and relies on the\n->add_bus callback (pci_ecam_add_bus) to populate the per-bus mapping in\ncfg->winp[]. pci_ecam_map_bus() then uses that mapping as the base for\nevery config access.\n\nThe generic ECAM ops (pci_generic_ecam_ops) already provide the ->add_bus\nand ->remove_bus callbacks, but the CAM (legacy) ops in pci-host-generic.c\ndo not. As a result, on a 32-bit host using \"pci-host-cam-generic\" the\nper-bus mapping is never set up and the first config read dereferences a\nNULL base, crashing during bus enumeration:\n\n Unable to handle kernel NULL pointer dereference at virtual address 00000800\n Oops [#1]\n CPU: 0 PID: 1 Comm: swapper Not tainted 6.9.7+ #43\n Hardware name: Digilent Nexys-Video-A7 RV32 (DT)\n epc : pci_generic_config_read+0x40/0xb0\n  ra : pci_generic_config_read+0x2c/0xb0\n [<c038db9c>] pci_generic_config_read+0x40/0xb0\n [<c038da04>] pci_bus_read_config_dword+0x50/0xb0\n [<c0391e94>] pci_bus_generic_read_dev_vendor_id+0x3c/0x1ec\n [<c039245c>] pci_scan_single_device+0xa4/0x11c\n [<c0392570>] pci_scan_slot+0x9c/0x23c\n [<c039388c>] pci_scan_child_bus_extend+0x58/0x2f4\n [<c0393db0>] pci_scan_root_bus_bridge+0x64/0xe8\n [<c0393e54>] pci_host_probe+0x20/0xc8\n [<c03bc6f4>] pci_host_common_probe+0x144/0x1e4\n\nFix this by giving the CAM ops the same ->add_bus/->remove_bus callbacks.\nSince pci_ecam_add_bus() and pci_ecam_remove_bus() are static to ecam.c,\nmove the CAM ops definition there as pci_generic_cam_ops (mirroring\npci_generic_ecam_ops) and export it for pci-host-generic.c to reference.\n\n[mani: removed timestamp from log]"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/pci/controller/pci-host-generic.c",
            "drivers/pci/ecam.c",
            "include/linux/pci-ecam.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "5e52eb0290f66ba0732956dcb1e365b5ca3c5108",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "baf9b0383ff770fdff123d3a832f3a99641d96dd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "8d08713ec83a18526d1ed1fd5f0d2b901d103a10",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "74456843f18ba7f3045974d7e8b88ab993152b8c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "0c55707bd5d0d7670704cfd0dda933809b052f67",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "a199293f3038db8d31d47aa60f1e18272cd82354",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "0916948026f623844acd08888f7cbedbf1c48d6b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fe55ef23387ce3c7488375b1fd539420d7654bb",
              "lessThan": "008cb88edb41f3c7c8e0ed763ff9f26719830984",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "0b5877a1aeacdbf32b3bea91326592004ec7806f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "a037ebbe72a4f98495b193112e2b2000e5e09eb5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5.12.19",
              "lessThan": "5.13",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "5.13.4",
              "lessThan": "5.14",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/pci/controller/pci-host-generic.c",
            "drivers/pci/ecam.c",
            "include/linux/pci-ecam.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.14",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.14",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.218",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.185",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.154",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.106",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.47",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.11",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.1",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/008cb88edb41f3c7c8e0ed763ff9f26719830984",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
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      "url": "https://git.kernel.org/stable/c/0916948026f623844acd08888f7cbedbf1c48d6b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/0c55707bd5d0d7670704cfd0dda933809b052f67",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5e52eb0290f66ba0732956dcb1e365b5ca3c5108",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/74456843f18ba7f3045974d7e8b88ab993152b8c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8d08713ec83a18526d1ed1fd5f0d2b901d103a10",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a199293f3038db8d31d47aa60f1e18272cd82354",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/baf9b0383ff770fdff123d3a832f3a99641d96dd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}