CVE-2025-40251
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: devlink: rate: Unset parent pointer in devl_rate_nodes_destroy The function devl_rate_nodes_destroy is documented to "Unset parent for all rate objects". However, it was only calling the driver-specific `rate_leaf_parent_set` or `rate_node_parent_set` ops and decrementing the parent's refcount, without actually setting the `devlink_rate->parent` pointer to NULL. This leaves a dangling pointer in the `devlink_rate` struct, which cause refcount error in netdevsim[1] and mlx5[2]. In addition, this is inconsistent with the behavior of `devlink_nl_rate_parent_node_set`, where the parent pointer is correctly cleared. This patch fixes the issue by explicitly setting `devlink_rate->parent` to NULL after notifying the driver, thus fulfilling the function's documented behavior for all rate objects. [1] repro steps: echo 1 > /sys/bus/netdevsim/new_device devlink dev eswitch set netdevsim/netdevsim1 mode switchdev echo 1 > /sys/bus/netdevsim/devices/netdevsim1/sriov_numvfs devlink port function rate add netdevsim/netdevsim1/test_node devlink port function rate set netdevsim/netdevsim1/128 parent test_node echo 1 > /sys/bus/netdevsim/del_device dmesg: refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 8 PID: 1530 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0 CPU: 8 UID: 0 PID: 1530 Comm: bash Not tainted 6.18.0-rc4+ #1 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:refcount_warn_saturate+0x42/0xe0 Call Trace: <TASK> devl_rate_leaf_destroy+0x8d/0x90 __nsim_dev_port_del+0x6c/0x70 [netdevsim] nsim_dev_reload_destroy+0x11c/0x140 [netdevsim] nsim_drv_remove+0x2b/0xb0 [netdevsim] device_release_driver_internal+0x194/0x1f0 bus_remove_device+0xc6/0x130 device_del+0x159/0x3c0 device_unregister+0x1a/0x60 del_device_store+0x111/0x170 [netdevsim] kernfs_fop_write_iter+0x12e/0x1e0 vfs_write+0x215/0x3d0 ksys_write+0x5f/0xd0 do_syscall_64+0x55/0x10f0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [2] devlink dev eswitch set pci/0000:08:00.0 mode switchdev devlink port add pci/0000:08:00.0 flavour pcisf pfnum 0 sfnum 1000 devlink port function rate add pci/0000:08:00.0/group1 devlink port function rate set pci/0000:08:00.0/32768 parent group1 modprobe -r mlx5_ib mlx5_fwctl mlx5_core dmesg: refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 7 PID: 16151 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0 CPU: 7 UID: 0 PID: 16151 Comm: bash Not tainted 6.17.0-rc7_for_upstream_min_debug_2025_10_02_12_44 #1 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 RIP: 0010:refcount_warn_saturate+0x42/0xe0 Call Trace: <TASK> devl_rate_leaf_destroy+0x8d/0x90 mlx5_esw_offloads_devlink_port_unregister+0x33/0x60 [mlx5_core] mlx5_esw_offloads_unload_rep+0x3f/0x50 [mlx5_core] mlx5_eswitch_unload_sf_vport+0x40/0x90 [mlx5_core] mlx5_sf_esw_event+0xc4/0x120 [mlx5_core] notifier_call_chain+0x33/0xa0 blocking_notifier_call_chain+0x3b/0x50 mlx5_eswitch_disable_locked+0x50/0x110 [mlx5_core] mlx5_eswitch_disable+0x63/0x90 [mlx5_core] mlx5_unload+0x1d/0x170 [mlx5_core] mlx5_uninit_one+0xa2/0x130 [mlx5_core] remove_one+0x78/0xd0 [mlx5_core] pci_device_remove+0x39/0xa0 device_release_driver_internal+0x194/0x1f0 unbind_store+0x99/0xa0 kernfs_fop_write_iter+0x12e/0x1e0 vfs_write+0x215/0x3d0 ksys_write+0x5f/0xd0 do_syscall_64+0x53/0x1f0 entry_SYSCALL_64_after_hwframe+0x4b/0x53
View original CVE JSON
{
"id": "CVE-2025-40251",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-12-04T16:16:18.663",
"lastModified": "2026-10-19T19:10:00.130",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndevlink: rate: Unset parent pointer in devl_rate_nodes_destroy\n\nThe function devl_rate_nodes_destroy is documented to \"Unset parent for\nall rate objects\". However, it was only calling the driver-specific\n`rate_leaf_parent_set` or `rate_node_parent_set` ops and decrementing\nthe parent's refcount, without actually setting the\n`devlink_rate->parent` pointer to NULL.\n\nThis leaves a dangling pointer in the `devlink_rate` struct, which cause\nrefcount error in netdevsim[1] and mlx5[2]. In addition, this is\ninconsistent with the behavior of `devlink_nl_rate_parent_node_set`,\nwhere the parent pointer is correctly cleared.\n\nThis patch fixes the issue by explicitly setting `devlink_rate->parent`\nto NULL after notifying the driver, thus fulfilling the function's\ndocumented behavior for all rate objects.\n\n[1]\nrepro steps:\necho 1 > /sys/bus/netdevsim/new_device\ndevlink dev eswitch set netdevsim/netdevsim1 mode switchdev\necho 1 > /sys/bus/netdevsim/devices/netdevsim1/sriov_numvfs\ndevlink port function rate add netdevsim/netdevsim1/test_node\ndevlink port function rate set netdevsim/netdevsim1/128 parent test_node\necho 1 > /sys/bus/netdevsim/del_device\n\ndmesg:\nrefcount_t: decrement hit 0; leaking memory.\nWARNING: CPU: 8 PID: 1530 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0\nCPU: 8 UID: 0 PID: 1530 Comm: bash Not tainted 6.18.0-rc4+ #1 NONE\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014\nRIP: 0010:refcount_warn_saturate+0x42/0xe0\nCall Trace:\n <TASK>\n devl_rate_leaf_destroy+0x8d/0x90\n __nsim_dev_port_del+0x6c/0x70 [netdevsim]\n nsim_dev_reload_destroy+0x11c/0x140 [netdevsim]\n nsim_drv_remove+0x2b/0xb0 [netdevsim]\n device_release_driver_internal+0x194/0x1f0\n bus_remove_device+0xc6/0x130\n device_del+0x159/0x3c0\n device_unregister+0x1a/0x60\n del_device_store+0x111/0x170 [netdevsim]\n kernfs_fop_write_iter+0x12e/0x1e0\n vfs_write+0x215/0x3d0\n ksys_write+0x5f/0xd0\n do_syscall_64+0x55/0x10f0\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\n[2]\ndevlink dev eswitch set pci/0000:08:00.0 mode switchdev\ndevlink port add pci/0000:08:00.0 flavour pcisf pfnum 0 sfnum 1000\ndevlink port function rate add pci/0000:08:00.0/group1\ndevlink port function rate set pci/0000:08:00.0/32768 parent group1\nmodprobe -r mlx5_ib mlx5_fwctl mlx5_core\n\ndmesg:\nrefcount_t: decrement hit 0; leaking memory.\nWARNING: CPU: 7 PID: 16151 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0\nCPU: 7 UID: 0 PID: 16151 Comm: bash Not tainted 6.17.0-rc7_for_upstream_min_debug_2025_10_02_12_44 #1 NONE\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\nRIP: 0010:refcount_warn_saturate+0x42/0xe0\nCall Trace:\n <TASK>\n devl_rate_leaf_destroy+0x8d/0x90\n mlx5_esw_offloads_devlink_port_unregister+0x33/0x60 [mlx5_core]\n mlx5_esw_offloads_unload_rep+0x3f/0x50 [mlx5_core]\n mlx5_eswitch_unload_sf_vport+0x40/0x90 [mlx5_core]\n mlx5_sf_esw_event+0xc4/0x120 [mlx5_core]\n notifier_call_chain+0x33/0xa0\n blocking_notifier_call_chain+0x3b/0x50\n mlx5_eswitch_disable_locked+0x50/0x110 [mlx5_core]\n mlx5_eswitch_disable+0x63/0x90 [mlx5_core]\n mlx5_unload+0x1d/0x170 [mlx5_core]\n mlx5_uninit_one+0xa2/0x130 [mlx5_core]\n remove_one+0x78/0xd0 [mlx5_core]\n pci_device_remove+0x39/0xa0\n device_release_driver_internal+0x194/0x1f0\n unbind_store+0x99/0xa0\n kernfs_fop_write_iter+0x12e/0x1e0\n vfs_write+0x215/0x3d0\n ksys_write+0x5f/0xd0\n do_syscall_64+0x53/0x1f0\n entry_SYSCALL_64_after_hwframe+0x4b/0x53"
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ndevlink: rate: Unset parent pointer in devl_rate_nodes_destroy\n\nLa función devl_rate_nodes_destroy está documentada para 'desestablecer el padre para todos los objetos de tasa'. Sin embargo, solo estaba llamando a las operaciones específicas del controlador 'rate_leaf_parent_set' o 'rate_node_parent_set' y decrementando el contador de referencias del padre, sin realmente establecer el puntero 'devlink_rate -> parent' a NULL.\n\nEsto deja un puntero colgante en la estructura 'devlink_rate', lo que causa un error de contador de referencias en netdevsim[1] y mlx5[2]. Además, esto es inconsistente con el comportamiento de 'devlink_nl_rate_parent_node_set', donde el puntero padre se borra correctamente.\n\nEste parche soluciona el problema al establecer explícitamente 'devlink_rate -> parent' a NULL después de notificar al controlador, cumpliendo así el comportamiento documentado de la función para todos los objetos de tasa.\n\n[1]\npasos de reproducción:\necho 1 > /sys/bus/netdevsim/new_device\ndevlink dev eswitch set netdevsim/netdevsim1 mode switchdev\necho 1 > /sys/bus/netdevsim/devices/netdevsim1/sriov_numvfs\ndevlink port function rate add netdevsim/netdevsim1/test_node\ndevlink port function rate set netdevsim/netdevsim1/128 parent test_node\necho 1 > /sys/bus/netdevsim/del_device\n\ndmesg:\nrefcount_t: decrement hit 0; leaking memory.\nWARNING: CPU: 8 PID: 1530 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0\nCPU: 8 UID: 0 PID: 1530 Comm: bash Not tainted 6.18.0-rc4+ #1 NONE\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014\nRIP: 0010:refcount_warn_saturate+0x42/0xe0\nCall Trace:\n <TASK>\n devl_rate_leaf_destroy+0x8d/0x90\n __nsim_dev_port_del+0x6c/0x70 [netdevsim]\n nsim_dev_reload_destroy+0x11c/0x140 [netdevsim]\n nsim_drv_remove+0x2b/0xb0 [netdevsim]\n device_release_driver_internal+0x194/0x1f0\n bus_remove_device+0xc6/0x130\n device_del+0x159/0x3c0\n device_unregister+0x1a/0x60\n del_device_store+0x111/0x170 [netdevsim]\n kernfs_fop_write_iter+0x12e/0x1e0\n vfs_write+0x215/0x3d0\n ksys_write+0x5f/0xd0\n do_syscall_64+0x55/0x10f0\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\n[2]\ndevlink dev eswitch set pci/0000:08:00.0 mode switchdev\ndevlink port add pci/0000:08:00.0 flavour pcisf pfnum 0 sfnum 1000\ndevlink port function rate add pci/0000:08:00.0/group1\ndevlink port function rate set pci/0000:08:00.0/32768 parent group1\nmodprobe -r mlx5_ib mlx5_fwctl mlx5_core\n\ndmesg:\nrefcount_t: decrement hit 0; leaking memory.\nWARNING: CPU: 7 PID: 16151 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0\nCPU: 7 UID: 0 PID: 16151 Comm: bash Not tainted 6.17.0-rc7_for_upstream_min_debug_2025_10_02_12_44 #1 NONE\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\nRIP: 0010:refcount_warn_saturate+0x42/0xe0\nCall Trace:\n <TASK>\n devl_rate_leaf_destroy+0x8d/0x90\n mlx5_esw_offloads_devlink_port_unregister+0x33/0x60 [mlx5_core]\n mlx5_esw_offloads_unload_rep+0x3f/0x50 [mlx5_core]\n mlx5_eswitch_unload_sf_vport+0x40/0x90 [mlx5_core]\n mlx5_sf_esw_event+0xc4/0x120 [mlx5_core]\n notifier_call_chain+0x33/0xa0\n blocking_notifier_call_chain+0x3b/0x50\n mlx5_eswitch_disable_locked+0x50/0x110 [mlx5_core]\n mlx5_eswitch_disable+0x63/0x90 [mlx5_core]\n mlx5_unload+0x1d/0x170 [mlx5_core]\n mlx5_uninit_one+0xa2/0x130 [mlx5_core]\n remove_one+0x78/0xd0 [mlx5_core]\n pci_device_remove+0x39/0xa0\n device_release_driver_internal+0x194/0x1f0\n unbind_store+0x99/0xa0\n kernfs_fop_write_iter+0x12e/0x1e0\n vfs_write+0x215/0x3d0\n ksys_write+0x5f/0xd0\n do_syscall_64+0x53/0x1f0\n entry_SYSCALL_64_after_hwframe+0x4b/0x53"
}
],
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{
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},
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},
{
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"defaultStatus": "affected",
"programFiles": [
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],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
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"status": "affected"
},
{
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"lessThan": "5.14",
"versionType": "semver",
"status": "unaffected"
},
{
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"lessThanOrEqual": "6.1.*",
"versionType": "semver",
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},
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},
{
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},
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},
{
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"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
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}
]
}
]
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"affectedData": [
{
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"product": "RUGGEDCOM RST2428P",
"defaultStatus": "unknown",
"versions": [
{
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"lessThan": "V4.0",
"versionType": "custom",
"status": "affected"
}
]
}
]
}
],
"metrics": {
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{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
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"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9
},
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-06-10T20:41:14.789338Z",
"id": "CVE-2025-40251",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-476"
}
]
}
],
"configurations": [
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{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-253495.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
]
}