CVE-2026-90433

What the bug is

The controller is allocated with the non-managed spi_alloc_host() while the interrupt is registered with devm_request_irq(). During removal, spi_bitbang_stop() only unregisters the controller; the subsequent spi_controller_put() then frees the controller together with its embedded driver-private devdata, which is the IRQ handler's dev_id. The devm_request_irq() release action (free_irq()), which drains the handler, does not run until after .remove() returns. A late or latched interrupt can therefore reach tiny_spi_irq() and dereference already-freed memory (e.g. hw->base). Switch to devm_spi_alloc_host() so that the devres LIFO order releases the controller only after free_irq() has drained the handler, and drop the now-redundant spi_controller_put() from .remove(). The probe error path is simplified to direct returns. This issue was found by an in-house static analysis tool.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

drivers/spi/spi-oc-tiny.c

What this is

SPI SUBSYSTEMMAINTAINERS section matched on drivers/spi/ · linux-spi@vger.kernel.org · Maintained

Kernel module

none to look for. The file would have gone into spi_oc_tiny, and Debian does not compile it into that module, so finding spi_oc_tiny in lsmod would say nothing about this CVE.

Check it on the machine

grep -wE 'CONFIG_SPI|CONFIG_SPI_OC_TINY' /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

Show whether Debian builds this, per release

Debian does not build this code. In 5 releases below, every kernel flavour Debian publishes has the switch off, so the vulnerable file is compiled into no kernel binary Debian ships.

• bookworm, trixie, forky, sid, bookworm · linux-6.12n

n

not enabled on any flavour - this release does not build the code

Build switches

CONFIG_SPI, CONFIG_SPI_OC_TINY

Reads as

all on means the file is compiled; any one off means it is not.

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-09-17 (31 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.3% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/spi

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
2.6.39	6.12.110	0260c94453a0
2.6.39	6.18.52	ef5cc4a8c088
2.6.39	7.2.6	1cd16c8d68f5
2.6.39	7.3	d710f43ce309

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