FKIE_CVE-2025-39831
Vulnerability from fkie_nvd - Published: 2025-09-16 14:15 - Updated: 2026-10-19 21:10
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5 (Medium) - CVSS:3.1/
Summary
In the Linux kernel, the following vulnerability has been resolved:
fbnic: Move phylink resume out of service_task and into open/close
The fbnic driver was presenting with the following locking assert coming
out of a PM resume:
[ 42.208116][ T164] RTNL: assertion failed at drivers/net/phy/phylink.c (2611)
[ 42.208492][ T164] WARNING: CPU: 1 PID: 164 at drivers/net/phy/phylink.c:2611 phylink_resume+0x190/0x1e0
[ 42.208872][ T164] Modules linked in:
[ 42.209140][ T164] CPU: 1 UID: 0 PID: 164 Comm: bash Not tainted 6.17.0-rc2-virtme #134 PREEMPT(full)
[ 42.209496][ T164] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-5.fc42 04/01/2014
[ 42.209861][ T164] RIP: 0010:phylink_resume+0x190/0x1e0
[ 42.210057][ T164] Code: 83 e5 01 0f 85 b0 fe ff ff c6 05 1c cd 3e 02 01 90 ba 33 0a 00 00 48 c7 c6 20 3a 1d a5 48 c7 c7 e0 3e 1d a5 e8 21 b8 90 fe 90 <0f> 0b 90 90 e9 86 fe ff ff e8 42 ea 1f ff e9 e2 fe ff ff 48 89 ef
[ 42.210708][ T164] RSP: 0018:ffffc90000affbd8 EFLAGS: 00010296
[ 42.210983][ T164] RAX: 0000000000000000 RBX: ffff8880078d8400 RCX: 0000000000000000
[ 42.211235][ T164] RDX: 0000000000000000 RSI: 1ffffffff4f10938 RDI: 0000000000000001
[ 42.211466][ T164] RBP: 0000000000000000 R08: ffffffffa2ae79ea R09: fffffbfff4b3eb84
[ 42.211707][ T164] R10: 0000000000000003 R11: 0000000000000000 R12: ffff888007ad8000
[ 42.211997][ T164] R13: 0000000000000002 R14: ffff888006a18800 R15: ffffffffa34c59e0
[ 42.212234][ T164] FS: 00007f0dc8e39740(0000) GS:ffff88808f51f000(0000) knlGS:0000000000000000
[ 42.212505][ T164] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 42.212704][ T164] CR2: 00007f0dc8e9fe10 CR3: 000000000b56d003 CR4: 0000000000772ef0
[ 42.213227][ T164] PKRU: 55555554
[ 42.213366][ T164] Call Trace:
[ 42.213483][ T164] <TASK>
[ 42.213565][ T164] __fbnic_pm_attach.isra.0+0x8e/0xa0
[ 42.213725][ T164] pci_reset_function+0x116/0x1d0
[ 42.213895][ T164] reset_store+0xa0/0x100
[ 42.214025][ T164] ? pci_dev_reset_attr_is_visible+0x50/0x50
[ 42.214221][ T164] ? sysfs_file_kobj+0xc1/0x1e0
[ 42.214374][ T164] ? sysfs_kf_write+0x65/0x160
[ 42.214526][ T164] kernfs_fop_write_iter+0x2f8/0x4c0
[ 42.214677][ T164] ? kernfs_vma_page_mkwrite+0x1f0/0x1f0
[ 42.214836][ T164] new_sync_write+0x308/0x6f0
[ 42.214987][ T164] ? __lock_acquire+0x34c/0x740
[ 42.215135][ T164] ? new_sync_read+0x6f0/0x6f0
[ 42.215288][ T164] ? lock_acquire.part.0+0xbc/0x260
[ 42.215440][ T164] ? ksys_write+0xff/0x200
[ 42.215590][ T164] ? perf_trace_sched_switch+0x6d0/0x6d0
[ 42.215742][ T164] vfs_write+0x65e/0xbb0
[ 42.215876][ T164] ksys_write+0xff/0x200
[ 42.215994][ T164] ? __ia32_sys_read+0xc0/0xc0
[ 42.216141][ T164] ? do_user_addr_fault+0x269/0x9f0
[ 42.216292][ T164] ? rcu_is_watching+0x15/0xd0
[ 42.216442][ T164] do_syscall_64+0xbb/0x360
[ 42.216591][ T164] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 42.216784][ T164] RIP: 0033:0x7f0dc8ea9986
A bit of digging showed that we were invoking the phylink_resume as a part
of the fbnic_up path when we were enabling the service task while not
holding the RTNL lock. We should be enabling this sooner as a part of the
ndo_open path and then just letting the service task come online later.
This will help to enforce the correct locking and brings the phylink
interface online at the same time as the network interface, instead of at a
later time.
I tested this on QEMU to verify this was working by putting the system to
sleep using "echo mem > /sys/power/state" to put the system to sleep in the
guest and then using the command "system_wakeup" in the QEMU monitor.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | 6.17 | |
| linux | linux_kernel | 6.17 | |
| linux | linux_kernel | 6.17 |
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/net/ethernet/meta/fbnic/fbnic_netdev.c",
"drivers/net/ethernet/meta/fbnic/fbnic_pci.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "7aab65c62a8a8b48c02e600fe9367b2af662fcb6",
"status": "affected",
"version": "69684376eed517817251ea6a768cfc315350d5c1",
"versionType": "git"
},
{
"lessThan": "3ac5f54e47eb348a4bc26e600c63b4d778a22e23",
"status": "affected",
"version": "69684376eed517817251ea6a768cfc315350d5c1",
"versionType": "git"
},
{
"lessThan": "6ede14a2c6365e7e5d855643c7c8390b5268c467",
"status": "affected",
"version": "69684376eed517817251ea6a768cfc315350d5c1",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/net/ethernet/meta/fbnic/fbnic_netdev.c",
"drivers/net/ethernet/meta/fbnic/fbnic_pci.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.11"
},
{
"lessThan": "6.11",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.45",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.16.*",
"status": "unaffected",
"version": "6.16.5",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "E85AB024-3CA8-4477-92B3-E99DB29C1EA2",
"versionEndExcluding": "6.12.45",
"versionStartIncluding": "6.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "EB781080-7001-4FA1-B388-517FFEFBC73E",
"versionEndExcluding": "6.16.5",
"versionStartIncluding": "6.13",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
"matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
"matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*",
"matchCriteriaId": "39982C4B-716E-4B2F-8196-FA301F47807D",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfbnic: Move phylink resume out of service_task and into open/close\n\nThe fbnic driver was presenting with the following locking assert coming\nout of a PM resume:\n[ 42.208116][ T164] RTNL: assertion failed at drivers/net/phy/phylink.c (2611)\n[ 42.208492][ T164] WARNING: CPU: 1 PID: 164 at drivers/net/phy/phylink.c:2611 phylink_resume+0x190/0x1e0\n[ 42.208872][ T164] Modules linked in:\n[ 42.209140][ T164] CPU: 1 UID: 0 PID: 164 Comm: bash Not tainted 6.17.0-rc2-virtme #134 PREEMPT(full)\n[ 42.209496][ T164] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-5.fc42 04/01/2014\n[ 42.209861][ T164] RIP: 0010:phylink_resume+0x190/0x1e0\n[ 42.210057][ T164] Code: 83 e5 01 0f 85 b0 fe ff ff c6 05 1c cd 3e 02 01 90 ba 33 0a 00 00 48 c7 c6 20 3a 1d a5 48 c7 c7 e0 3e 1d a5 e8 21 b8 90 fe 90 \u003c0f\u003e 0b 90 90 e9 86 fe ff ff e8 42 ea 1f ff e9 e2 fe ff ff 48 89 ef\n[ 42.210708][ T164] RSP: 0018:ffffc90000affbd8 EFLAGS: 00010296\n[ 42.210983][ T164] RAX: 0000000000000000 RBX: ffff8880078d8400 RCX: 0000000000000000\n[ 42.211235][ T164] RDX: 0000000000000000 RSI: 1ffffffff4f10938 RDI: 0000000000000001\n[ 42.211466][ T164] RBP: 0000000000000000 R08: ffffffffa2ae79ea R09: fffffbfff4b3eb84\n[ 42.211707][ T164] R10: 0000000000000003 R11: 0000000000000000 R12: ffff888007ad8000\n[ 42.211997][ T164] R13: 0000000000000002 R14: ffff888006a18800 R15: ffffffffa34c59e0\n[ 42.212234][ T164] FS: 00007f0dc8e39740(0000) GS:ffff88808f51f000(0000) knlGS:0000000000000000\n[ 42.212505][ T164] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 42.212704][ T164] CR2: 00007f0dc8e9fe10 CR3: 000000000b56d003 CR4: 0000000000772ef0\n[ 42.213227][ T164] PKRU: 55555554\n[ 42.213366][ T164] Call Trace:\n[ 42.213483][ T164] \u003cTASK\u003e\n[ 42.213565][ T164] __fbnic_pm_attach.isra.0+0x8e/0xa0\n[ 42.213725][ T164] pci_reset_function+0x116/0x1d0\n[ 42.213895][ T164] reset_store+0xa0/0x100\n[ 42.214025][ T164] ? pci_dev_reset_attr_is_visible+0x50/0x50\n[ 42.214221][ T164] ? sysfs_file_kobj+0xc1/0x1e0\n[ 42.214374][ T164] ? sysfs_kf_write+0x65/0x160\n[ 42.214526][ T164] kernfs_fop_write_iter+0x2f8/0x4c0\n[ 42.214677][ T164] ? kernfs_vma_page_mkwrite+0x1f0/0x1f0\n[ 42.214836][ T164] new_sync_write+0x308/0x6f0\n[ 42.214987][ T164] ? __lock_acquire+0x34c/0x740\n[ 42.215135][ T164] ? new_sync_read+0x6f0/0x6f0\n[ 42.215288][ T164] ? lock_acquire.part.0+0xbc/0x260\n[ 42.215440][ T164] ? ksys_write+0xff/0x200\n[ 42.215590][ T164] ? perf_trace_sched_switch+0x6d0/0x6d0\n[ 42.215742][ T164] vfs_write+0x65e/0xbb0\n[ 42.215876][ T164] ksys_write+0xff/0x200\n[ 42.215994][ T164] ? __ia32_sys_read+0xc0/0xc0\n[ 42.216141][ T164] ? do_user_addr_fault+0x269/0x9f0\n[ 42.216292][ T164] ? rcu_is_watching+0x15/0xd0\n[ 42.216442][ T164] do_syscall_64+0xbb/0x360\n[ 42.216591][ T164] entry_SYSCALL_64_after_hwframe+0x4b/0x53\n[ 42.216784][ T164] RIP: 0033:0x7f0dc8ea9986\n\nA bit of digging showed that we were invoking the phylink_resume as a part\nof the fbnic_up path when we were enabling the service task while not\nholding the RTNL lock. We should be enabling this sooner as a part of the\nndo_open path and then just letting the service task come online later.\nThis will help to enforce the correct locking and brings the phylink\ninterface online at the same time as the network interface, instead of at a\nlater time.\n\nI tested this on QEMU to verify this was working by putting the system to\nsleep using \"echo mem \u003e /sys/power/state\" to put the system to sleep in the\nguest and then using the command \"system_wakeup\" in the QEMU monitor."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nfbnic: Mover la reanudaci\u00f3n de phylink fuera de service_task y hacia open/close\n\nEl controlador fbnic estaba presentando la siguiente aserci\u00f3n de bloqueo saliendo de una reanudaci\u00f3n de PM:\n[ 42.208116][ T164] RTNL: aserci\u00f3n fallida en drivers/net/phy/phylink.c (2611)\n[ 42.208492][ T164] ADVERTENCIA: CPU: 1 PID: 164 en drivers/net/phy/phylink.c:2611 phylink_resume+0x190/0x1e0\n[ 42.208872][ T164] M\u00f3dulos enlazados:\n[ 42.209140][ T164] CPU: 1 UID: 0 PID: 164 Comm: bash No contaminado 6.17.0-rc2-virtme #134 PREEMPT(full)\n[ 42.209496][ T164] Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-5.fc42 04/01/2014\n[ 42.209861][ T164] RIP: 0010:phylink_resume+0x190/0x1e0\n[ 42.210057][ T164] C\u00f3digo: 83 e5 01 0f 85 b0 fe ff ff c6 05 1c cd 3e 02 01 90 ba 33 0a 00 00 48 c7 c6 20 3a 1d a5 48 c7 c7 e0 3e 1d a5 e8 21 b8 90 fe 90 \u003c0f\u003e 0b 90 90 e9 86 fe ff ff e8 42 ea 1f ff e9 e2 fe ff ff 48 89 ef\n[ 42.210708][ T164] RSP: 0018:ffffc90000affbd8 EFLAGS: 00010296\n[ 42.210983][ T164] RAX: 0000000000000000 RBX: ffff8880078d8400 RCX: 0000000000000000\n[ 42.211235][ T164] RDX: 0000000000000000 RSI: 1ffffffff4f10938 RDI: 0000000000000001\n[ 42.211466][ T164] RBP: 0000000000000000 R08: ffffffffa2ae79ea R09: fffffbfff4b3eb84\n[ 42.211707][ T164] R10: 0000000000000003 R11: 0000000000000000 R12: ffff888007ad8000\n[ 42.211997][ T164] R13: 0000000000000002 R14: ffff888006a18800 R15: ffffffffa34c59e0\n[ 42.212234][ T164] FS: 00007f0dc8e39740(0000) GS:ffff88808f51f000(0000) knlGS:0000000000000000\n[ 42.212505][ T164] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 42.212704][ T164] CR2: 00007f0dc8e9fe10 CR3: 000000000b56d003 CR4: 0000000000772ef0\n[ 42.213227][ T164] PKRU: 55555554\n[ 42.213366][ T164] Traza de llamada:\n[ 42.213483][ T164] \u003cTAREA\u003e\n[ 42.213565][ T164] __fbnic_pm_attach.isra.0+0x8e/0xa0\n[ 42.213725][ T164] pci_reset_function+0x116/0x1d0\n[ 42.213895][ T164] reset_store+0xa0/0x100\n[ 42.214025][ T164] ? pci_dev_reset_attr_is_visible+0x50/0x50\n[ 42.214221][ T164] ? sysfs_file_kobj+0xc1/0x1e0\n[ 42.214374][ T164] ? sysfs_kf_write+0x65/0x160\n[ 42.214526][ T164] kernfs_fop_write_iter+0x2f8/0x4c0\n[ 42.214677][ T164] ? kernfs_vma_page_mkwrite+0x1f0/0x1f0\n[ 42.214836][ T164] new_sync_write+0x308/0x6f0\n[ 42.214987][ T164] ? __lock_acquire+0x34c/0x740\n[ 42.215135][ T164] ? new_sync_read+0x6f0/0x6f0\n[ 42.215288][ T164] ? lock_acquire.part.0+0xbc/0x260\n[ 42.215440][ T164] ? ksys_write+0xff/0x200\n[ 42.215590][ T164] ? perf_trace_sched_switch+0x6d0/0x6d0\n[ 42.215742][ T164] vfs_write+0x65e/0xbb0\n[ 42.215876][ T164] ksys_write+0xff/0x200\n[ 42.215994][ T164] ? __ia32_sys_read+0xc0/0xc0\n[ 42.216141][ T164] ? do_user_addr_fault+0x269/0x9f0\n[ 42.216292][ T164] ? rcu_is_watching+0x15/0xd0\n[ 42.216442][ T164] do_syscall_64+0xbb/0x360\n[ 42.216591][ T164] entry_SYSCALL_64_after_hwframe+0x4b/0x53\n[ 42.216784][ T164] RIP: 0033:0x7f0dc8ea9986\n\nUn poco de investigaci\u00f3n mostr\u00f3 que est\u00e1bamos invocando phylink_resume como parte de la ruta fbnic_up cuando est\u00e1bamos habilitando la tarea de servicio sin mantener el bloqueo RTNL. Deber\u00edamos habilitar esto antes como parte de la ruta ndo_open y luego simplemente dejar que la tarea de servicio se conecte m\u00e1s tarde. Esto ayudar\u00e1 a hacer cumplir el bloqueo correcto y pone la interfaz phylink en"
}
],
"id": "CVE-2025-39831",
"lastModified": "2026-10-19T21:10:00.160",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6,
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2025-39831",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-14T18:17:53.506262Z",
"version": "2.0.3"
}
}
]
},
"published": "2025-09-16T14:15:51.320",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/3ac5f54e47eb348a4bc26e600c63b4d778a22e23"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/6ede14a2c6365e7e5d855643c7c8390b5268c467"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/7aab65c62a8a8b48c02e600fe9367b2af662fcb6"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
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