Bug 2495944 (CVE-2026-53332)

Summary: CVE-2026-53332 kernel: slimbus: qcom-ngd-ctrl: Register callbacks after creating the ngd
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's Qualcomm NGD (Next Generation Display) controller (qcom-ngd-ctrl) component. This vulnerability arises from a race condition where callbacks are registered before the NGD device is fully initialized. This can lead to the callbacks operating on uninitialized data, potentially causing system instability, boot issues, and a denial of service on affected boards.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-07-01 14:02:40 UTC
In the Linux kernel, the following vulnerability has been resolved:

slimbus: qcom-ngd-ctrl: Register callbacks after creating the ngd

When the remoteproc starts in parallel with the NGD driver being probed,
or the remoteproc is already up when the PDR lookup is being registered,
or in the theoretical event that we get an interrupt from the hardware,
these callbacks will operate on uninitialized data. This result in
issues to boot the affected boards.

One such example can be seen in the following fault, where
qcom_slim_ngd_ssr_pdr_notify() schedules work on the NULL ngd_up_work.

[   21.858578] ------------[ cut here ]------------
[   21.858745] WARNING: kernel/workqueue.c:2338 at __queue_work+0x5e0/0x790, CPU#2: kworker/2:2/116
...
[   21.859251] Call trace:
[   21.859255]  __queue_work+0x5e0/0x790 (P)
[   21.859265]  queue_work_on+0x6c/0xf0
[   21.859273]  qcom_slim_ngd_ssr_pdr_notify+0x110/0x150 [slim_qcom_ngd_ctrl]
[   21.859304]  qcom_slim_ngd_ssr_notify+0x24/0x40 [slim_qcom_ngd_ctrl]
[   21.859318]  notifier_call_chain+0xa4/0x230
[   21.859329]  srcu_notifier_call_chain+0x64/0xb8
[   21.859338]  ssr_notify_start+0x40/0x78 [qcom_common]
[   21.859355]  rproc_start+0x130/0x230
[   21.859367]  rproc_boot+0x3d4/0x518
...

Move the enablement of interrupts, and the registration of SSR and PDR
until after the NGD device has been registered.

This could be further refined by moving initialization to the control
driver probe and by removing the platform driver model from the picture.

Comment 1 Mauro Matteo Cascella 2026-07-01 17:20:24 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026070142-CVE-2026-53332-639c@gregkh/T