ghsa-4mj4-9wgf-mxj5
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
PCI: Fix link speed calculation on retrain failure
When pcie_failed_link_retrain() fails to retrain, it tries to revert to the previous link speed. However it calculates that speed from the Link Control 2 register without masking out non-speed bits first.
PCIE_LNKCTL2_TLS2SPEED() converts such incorrect values to PCI_SPEED_UNKNOWN (0xff), which in turn causes a WARN splat in pcie_set_target_speed():
pci 0000:00:01.1: [1022:14ed] type 01 class 0x060400 PCIe Root Port pci 0000:00:01.1: broken device, retraining non-functional downstream link at 2.5GT/s pci 0000:00:01.1: retraining failed WARNING: CPU: 1 PID: 1 at drivers/pci/pcie/bwctrl.c:168 pcie_set_target_speed RDX: 0000000000000001 RSI: 00000000000000ff RDI: ffff9acd82efa000 pcie_failed_link_retrain pci_device_add pci_scan_single_device
Mask out the non-speed bits in PCIE_LNKCTL2_TLS2SPEED() and PCIE_LNKCAP_SLS2SPEED() so they don't incorrectly return PCI_SPEED_UNKNOWN.
[bhelgaas: commit log, add details from https://lore.kernel.org/r/1c92ef6bcb314ee6977839b46b393282e4f52e74.1750684771.git.lukas@wunner.de]
{
"affected": [],
"aliases": [
"CVE-2025-39784"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-11T17:15:44Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nPCI: Fix link speed calculation on retrain failure\n\nWhen pcie_failed_link_retrain() fails to retrain, it tries to revert to the\nprevious link speed. However it calculates that speed from the Link\nControl 2 register without masking out non-speed bits first.\n\nPCIE_LNKCTL2_TLS2SPEED() converts such incorrect values to\nPCI_SPEED_UNKNOWN (0xff), which in turn causes a WARN splat in\npcie_set_target_speed():\n\n pci 0000:00:01.1: [1022:14ed] type 01 class 0x060400 PCIe Root Port\n pci 0000:00:01.1: broken device, retraining non-functional downstream link at 2.5GT/s\n pci 0000:00:01.1: retraining failed\n WARNING: CPU: 1 PID: 1 at drivers/pci/pcie/bwctrl.c:168 pcie_set_target_speed\n RDX: 0000000000000001 RSI: 00000000000000ff RDI: ffff9acd82efa000\n pcie_failed_link_retrain\n pci_device_add\n pci_scan_single_device\n\nMask out the non-speed bits in PCIE_LNKCTL2_TLS2SPEED() and\nPCIE_LNKCAP_SLS2SPEED() so they don\u0027t incorrectly return PCI_SPEED_UNKNOWN.\n\n[bhelgaas: commit log, add details from https://lore.kernel.org/r/1c92ef6bcb314ee6977839b46b393282e4f52e74.1750684771.git.lukas@wunner.de]",
"id": "GHSA-4mj4-9wgf-mxj5",
"modified": "2025-09-11T18:35:52Z",
"published": "2025-09-11T18:35:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39784"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/16557320f378262b5c605b15edebd3642406992a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9989e0ca7462c62f93dbc62f684448aa2efb9226"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
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