Description
In the Linux kernel, the following vulnerability has been resolved:
accel/rocket: search every core slot when a core is removed
rocket_remove() decrements rdev->num_cores for each core it removes,
while find_core_for_dev() searches slots 0 to num_cores - 1. Unbinding
the cores in the order they were bound therefore loses the last one: by
the time it is removed the search range has already shrunk past its
slot, so find_core_for_dev() returns -1 and rocket_remove() gives up
without doing anything.
num_cores never reaches zero, rocket_device_fini() never runs, and the
file-scoped rdev keeps pointing at a device that is going away. Binding
the cores again starts from that stale count, because rocket_probe()
takes rdev->num_cores as the slot to fill. On an RK3588, which describes
three cores, the second round lands on slots 1, 2 and 3 while rdev->cores
was allocated with room for three:
rocket fdab0000.npu: Rockchip NPU core 1 version: 1179210309
rocket fdac0000.npu: Rockchip NPU core 2 version: 1179210309
rocket fdad0000.npu: Rockchip NPU core 3 version: 1179210309
The write to rdev->cores[3] is past the end of the array.
Nothing in tree reads the core array often enough to notice, so the
overrun is silent today. It turned up while testing a devfreq series on
top of this, where a worker walks every core a few times a second, and
UBSAN caught the first bool it read out of the overrun entry:
UBSAN: invalid-load in drivers/accel/rocket/rocket_devfreq.c:47:10
load of value 5 is not a valid value for type '_Bool'
Workqueue: devfreq_wq devfreq_monitor
Record how many slots were allocated and search all of them. Every core
is then found on removal, num_cores reaches zero, the device is torn down
and a later bind starts from a clean rdev.
This does not make unbinding a single core out of several work. probe
still takes num_cores as the slot to fill, so rebinding one core while
its siblings stay bound would write over a slot that is already in use,
and rocket_open() still reaches for cores[0] whether or not anything is
there. Both of those want more thought than a fix should carry.
Found by unbinding and rebinding all three cores on an Orange Pi 5 Plus.
With this applied, 25 unbind/rebind rounds and 5 module unload/reload
rounds run clean there: the cores land in slots 0, 1 and 2 every time,
whichever order they are bound in, and the shared supply goes back to a
single user after each round.
accel/rocket: search every core slot when a core is removed
rocket_remove() decrements rdev->num_cores for each core it removes,
while find_core_for_dev() searches slots 0 to num_cores - 1. Unbinding
the cores in the order they were bound therefore loses the last one: by
the time it is removed the search range has already shrunk past its
slot, so find_core_for_dev() returns -1 and rocket_remove() gives up
without doing anything.
num_cores never reaches zero, rocket_device_fini() never runs, and the
file-scoped rdev keeps pointing at a device that is going away. Binding
the cores again starts from that stale count, because rocket_probe()
takes rdev->num_cores as the slot to fill. On an RK3588, which describes
three cores, the second round lands on slots 1, 2 and 3 while rdev->cores
was allocated with room for three:
rocket fdab0000.npu: Rockchip NPU core 1 version: 1179210309
rocket fdac0000.npu: Rockchip NPU core 2 version: 1179210309
rocket fdad0000.npu: Rockchip NPU core 3 version: 1179210309
The write to rdev->cores[3] is past the end of the array.
Nothing in tree reads the core array often enough to notice, so the
overrun is silent today. It turned up while testing a devfreq series on
top of this, where a worker walks every core a few times a second, and
UBSAN caught the first bool it read out of the overrun entry:
UBSAN: invalid-load in drivers/accel/rocket/rocket_devfreq.c:47:10
load of value 5 is not a valid value for type '_Bool'
Workqueue: devfreq_wq devfreq_monitor
Record how many slots were allocated and search all of them. Every core
is then found on removal, num_cores reaches zero, the device is torn down
and a later bind starts from a clean rdev.
This does not make unbinding a single core out of several work. probe
still takes num_cores as the slot to fill, so rebinding one core while
its siblings stay bound would write over a slot that is already in use,
and rocket_open() still reaches for cores[0] whether or not anything is
there. Both of those want more thought than a fix should carry.
Found by unbinding and rebinding all three cores on an Orange Pi 5 Plus.
With this applied, 25 unbind/rebind rounds and 5 module unload/reload
rounds run clean there: the cores land in slots 0, 1 and 2 every time,
whichever order they are bound in, and the shared supply goes back to a
single user after each round.
Published:
2026-10-28
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
No analysis available yet.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
No advisories yet.
References
History
Wed, 28 Oct 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: accel/rocket: search every core slot when a core is removed rocket_remove() decrements rdev->num_cores for each core it removes, while find_core_for_dev() searches slots 0 to num_cores - 1. Unbinding the cores in the order they were bound therefore loses the last one: by the time it is removed the search range has already shrunk past its slot, so find_core_for_dev() returns -1 and rocket_remove() gives up without doing anything. num_cores never reaches zero, rocket_device_fini() never runs, and the file-scoped rdev keeps pointing at a device that is going away. Binding the cores again starts from that stale count, because rocket_probe() takes rdev->num_cores as the slot to fill. On an RK3588, which describes three cores, the second round lands on slots 1, 2 and 3 while rdev->cores was allocated with room for three: rocket fdab0000.npu: Rockchip NPU core 1 version: 1179210309 rocket fdac0000.npu: Rockchip NPU core 2 version: 1179210309 rocket fdad0000.npu: Rockchip NPU core 3 version: 1179210309 The write to rdev->cores[3] is past the end of the array. Nothing in tree reads the core array often enough to notice, so the overrun is silent today. It turned up while testing a devfreq series on top of this, where a worker walks every core a few times a second, and UBSAN caught the first bool it read out of the overrun entry: UBSAN: invalid-load in drivers/accel/rocket/rocket_devfreq.c:47:10 load of value 5 is not a valid value for type '_Bool' Workqueue: devfreq_wq devfreq_monitor Record how many slots were allocated and search all of them. Every core is then found on removal, num_cores reaches zero, the device is torn down and a later bind starts from a clean rdev. This does not make unbinding a single core out of several work. probe still takes num_cores as the slot to fill, so rebinding one core while its siblings stay bound would write over a slot that is already in use, and rocket_open() still reaches for cores[0] whether or not anything is there. Both of those want more thought than a fix should carry. Found by unbinding and rebinding all three cores on an Orange Pi 5 Plus. With this applied, 25 unbind/rebind rounds and 5 module unload/reload rounds run clean there: the cores land in slots 0, 1 and 2 every time, whichever order they are bound in, and the shared supply goes back to a single user after each round. | |
| Title | accel/rocket: search every core slot when a core is removed | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-28T10:35:42.469Z
Reserved: 2026-09-25T10:25:14.399Z
Link: CVE-2026-99184
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-28T11:17:39.243
Modified: 2026-10-28T11:17:39.243
Link: CVE-2026-99184
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.