CVE-2026-93098

What the bug is

During driver detach, the device core holds the device mutex throughout the driver's remove callback chain. When the rpmsg endpoint is destroyed as part of that teardown, the GLINK endpoint destroy implementation attempts to unregister the underlying rpmsg device. That unregistration calls device_del(), which tries to re-acquire the same device mutex already held higher up the stack, causing rmmod to hang indefinitely. The deadlock manifests with the following call chain: [<0>] device_del+0x44/0x414  <- tries to acquire same mutex [<0>] device_unregister+0x18/0x34 [<0>] rpmsg_unregister_device+0x28/0x4c [<0>] qcom_glink_remove_rpmsg_device+0x70/0xc0 [<0>] qcom_glink_destroy_ept+0x58/0xbc [<0>] rpmsg_dev_remove+0x50/0x60 [<0>] device_remove+0x4c/0x80 [<0>] device_release_driver_internal+0x1cc/0x228 <- acquires device mutex [<0>] driver_detach+0x4c/0x98 [<0>] bus_remove_driver+0x6c/0xbc [<0>] driver_unregister+0x30/0x60 [<0>] unregister_rpmsg_driver+0x10/0x1c [<0>] fastrpc_exit+0x28/0x38 [fastrpc] [<0>] __arm64_sys_delete_module+0x1b8/0x294 [<0>] invoke_syscall+0x48/0x10c [<0>] el0_svc_common.constprop.0+0xc0/0xe0 [<0>] do_el0_svc+0x1c/0x28 [<0>] el0_svc+0x34/0x108 [<0>] el0t_64_sync_handler+0xa0/0xe4 [<0>] el0t_64_sync+0x198/0x19c The rpmsg device unregistration inside endpoint destroy is redundant. In both contexts where endpoint destruction is triggered: - Driver detach path: the driver core already tears down the rpmsg device. - Channel close path: the rpmsg device is already unregistered before endpoint destruction is reached. Remove the redundant unregistration to fix the deadlock.

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/rpmsg/qcom_glink_native.c

What this is

ARM/QUALCOMM MAILING LISTMAINTAINERS section matched on drivers/*/qcom* · linux-arm-msm@vger.kernel.org

Kernel module

qcom_glink

Check it on the machine

grep -wE 'CONFIG_RPMSG|CONFIG_RPMSG_QCOM_GLINK' /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.

lsmod | grep -w qcom_glink

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookwormMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, i386/686, i386/686-pae, i386/rt/686-pae, ppc64el/powerpc64le
• trixieMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armel/rpi, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, riscv64/riscv64, s390x/s390x
• forky, sidYnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt-amd64, arm64/cloud-arm64, armhf/armmp, armhf/armmp-lpae, loong64/loong64, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, riscv64/riscv64, s390x/s390x
• bookworm · linux-6.12Mnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, ppc64el/powerpc64le, ppc64el/powerpc64le-64k

M

a module where it is built at all; some flavours do not build it

Y

built in where it is built at all; some flavours do not build it

Build switches

CONFIG_RPMSG, CONFIG_RPMSG_QCOM_GLINK

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 10.6% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/rpmsg

Upstream fixes

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

Introduced	Fixed in	Commit
5.10.248	5.10.270	73092c2292aa
5.15.198	5.15.221	bbc236357876
6.1.160	6.1.188	8597f669a526
6.6.120	6.6.157	48f55b90f0d7
6.12.64	6.12.110	cbcdf96e1c87
6.18.3	6.18.52	ecad679e2b92
6.19	7.2.6	e559626bee8a
6.19	7.3	5a5a48e788e0

Debian advisories