CVE-2026-74418

What the bug is

Trace_dma_fence_signaled, trace_dma_fence_wait_end and trace_dma_fence_destroy can all currently dereference a null fence->ops pointer after it has been reset on fence signalling. Lets use the safe string getters for most tracepoints to avoid this class of a problem, while for the signal tracepoint we move it to before ops are cleared to avoid losing the driver and timeline name information. Apart from moving it we also need to add a new tracepoint class to bypass the safe name getters since the signaled bit is already set. For dma_fence_init we also need to use the new tracepoint class since the rcu read lock is not held there, and we can do the same for the enable signaling since there we are certain the fence cannot be signaled while we are holding the lock and have even validated the fence->ops.

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/dma-buf/dma-fence.c
include/trace/events/dma_fence.h

What this is

SYNC FILE FRAMEWORKMAINTAINERS section matched on drivers/dma-buf/dma-fence* · linux-media@vger.kernel.org · Maintained

Check it on the machine

grep -w CONFIG_DMA_SHARED_BUFFER /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 builds this code. Every release below compiles the affected file into the kernels it ships.

• bookworm, trixie, forky, sidy

y

built into the kernel image on every flavour - only a patch removes it

Build switch

CONFIG_DMA_SHARED_BUFFER

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

2026-08-15 (2 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.5% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

drivers/dma-buf

Upstream fixes

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

Introduced	Fixed in	Commit
7.1	7.1.5	4e01fc9a5bc4
7.1	7.2	e94b9f01543c