CVE-2026-98020 affecting package kernel 6.6.157.1-1
In the Linux kernel, the following vulnerability has been resolved: pds_core: fix cmd_regs access racing BAR unmap on reset pdsc_reset_prepare() and pdsc_reset_done()'s pdsc_map_bars() error path clear/iounmap cmd_regs without devcmd_lock, and pdsc_legacy_firmware_update()'s download loop derefs cmd_regs after dropping and retaking the lock without re-checking. An FLR concurrent with a devlink flash can unmap cmd_regs under an in-flight devcmd, causing a NULL deref or a write to unmapped MMIO. Take devcmd_lock across the BAR unmap/remap, and re-check cmd_regs in the download loop. Only the PF maps cmd_regs and runs devcmd, so skip the unmap on a VF, as pdsc_remove() and pdsc_reset_done() already do. A reset that completes entirely within the unlocked window is not a correctness problem for the image: the device clears its update session, so a resumed download is rejected, and it verifies the staged image before writing a flash slot, reporting PDS_RC_BAD_FW rather than activating it. pdsc_unmap_bars() also clears info_regs, intr_status and intr_ctrl. The interrupt and start/stop readers of those are quiesced before the unmap by pdsc_fw_down(), which frees the interrupts and tears down the queues. The debugfs readers are not, since those files outlive a reset; that is pre-existing and out of scope here.
- Products
- kernel
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-98020
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 17:42 UTC · Revision 1
Source evidence
CVE-2026-98020 affecting package kernel 6.6.157.1-1
core-osv · Original sourcePublished 25 Sept 2026, 11:17 UTC
In the Linux kernel, the following vulnerability has been resolved: pds_core: fix cmd_regs access racing BAR unmap on reset pdsc_reset_prepare() and pdsc_reset_done()'s pdsc_map_bars() error path clear/iounmap cmd_regs without devcmd_lock, and pdsc_legacy_firmware_update()'s download loop derefs cmd_regs after dropping and retaking the lock without re-checking. An FLR concurrent with a devlink flash can unmap cmd_regs under an in-flight devcmd, causing a NULL deref or a write to unmapped MMIO. Take devcmd_lock across the BAR unmap/remap, and re-check cmd_regs in the download loop. Only the PF maps cmd_regs and runs devcmd, so skip the unmap on a VF, as pdsc_remove() and pdsc_reset_done() already do. A reset that completes entirely within the unlocked window is not a correctness problem for the image: the device clears its update session, so a resumed download is rejected, and it verifies the staged image before writing a flash slot, reporting PDS_RC_BAD_FW rather than activating it. pdsc_unmap_bars() also clears info_regs, intr_status and intr_ctrl. The interrupt and start/stop readers of those are quiesced before the unmap by pdsc_fw_down(), which frees the interrupts and tears down the queues. The debugfs readers are not, since those files outlive a reset; that is pre-existing and out of scope here.
osv:AZL-104229
kernel
Fixed versions: Not specified
Complete source record
{
"id": "368f426cb25b7f226fbf28fe4fa8388f783bd5616316151f5ce11b13fc9e029c",
"url": "https://osv.dev/vulnerability/AZL-104229",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2026-98020 affecting package kernel 6.6.157.1-1",
"summary": "In the Linux kernel, the following vulnerability has been resolved: pds_core: fix cmd_regs access racing BAR unmap on reset pdsc_reset_prepare() and pdsc_reset_done()'s pdsc_map_bars() error path clear/iounmap cmd_regs without devcmd_lock, and pdsc_legacy_firmware_update()'s download loop derefs cmd_regs after dropping and retaking the lock without re-checking. An FLR concurrent with a devlink flash can unmap cmd_regs under an in-flight devcmd, causing a NULL deref or a write to unmapped MMIO. Take devcmd_lock across the BAR unmap/remap, and re-check cmd_regs in the download loop. Only the PF maps cmd_regs and runs devcmd, so skip the unmap on a VF, as pdsc_remove() and pdsc_reset_done() already do. A reset that completes entirely within the unlocked window is not a correctness problem for the image: the device clears its update session, so a resumed download is rejected, and it verifies the staged image before writing a flash slot, reporting PDS_RC_BAD_FW rather than activating it. pdsc_unmap_bars() also clears info_regs, intr_status and intr_ctrl. The interrupt and start/stop readers of those are quiesced before the unmap by pdsc_fw_down(), which frees the interrupts and tears down the queues. The debugfs readers are not, since those files outlive a reset; that is pre-existing and out of scope here.",
"evidence": "osv:AZL-104229",
"products": [
{
"name": {
"value": "kernel",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "AZL-104229",
"aliases": [
"AZL-104229"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"last_affected": "6.6.157.1-1"
}
]
}
],
"package": {
"name": "kernel",
"purl": "pkg:rpm/azure-linux/kernel",
"ecosystem": "Azure Linux:3"
},
"database_specific": {
"source": "https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-104229.json"
}
}
],
"modified": "2026-10-22T05:35:55Z",
"provider": "osv",
"upstream": [
"CVE-2026-98020"
],
"references": [
"https://nvd.nist.gov/vuln/detail/CVE-2026-98020"
]
},
"related_cves": [
{
"value": "CVE-2026-98020",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 404420,
"published_at": "2026-09-25T11:17:30+00:00"
}