CVEvulnerability
CVE-2026-93098
- Status
- Received
- Published
- 2026-09-17
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
rpmsg: glink: fix deadlock in endpoint destroy during driver detach
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.
References
- https://git.kernel.org/stable/c/48f55b90f0d713e477e26b85d7327d9592d016f9 git.kernel.org
- https://git.kernel.org/stable/c/5a5a48e788e02fd8a8eb7188ce440572d6c12418 git.kernel.org
- https://git.kernel.org/stable/c/73092c2292aa65515671e54abbcda2166d3827ed git.kernel.org
- https://git.kernel.org/stable/c/8597f669a5268e0dcf243e2b2d6ca00370117057 git.kernel.org
- https://git.kernel.org/stable/c/bbc236357876d35a624030e5c50eedbc380be98e git.kernel.org
- https://git.kernel.org/stable/c/cbcdf96e1c87bc07055d04264018ded1f3bafffb git.kernel.org
- https://git.kernel.org/stable/c/e559626bee8a6632aafc08eedcdb4bf26ca245c5 git.kernel.org
- https://git.kernel.org/stable/c/ecad679e2b92c419cc22cc8f257cd457d5192647 git.kernel.org