CVE-2024-46680 Bluetooth: btnxpuart: Fix random crash seen while removing driver

High 7.8 Published 13 Sep 2024 Updated 5 Aug 2026

A use-after-free vulnerability in the Linux kernel btnxpuart Bluetooth driver causes a system crash when the driver is removed while power save work is scheduled.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2024-46680?

CVE-2024-46680 is a high-severity use after free vulnerability in Linux kernel, published on 13 Sep 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: btnxpuart: Fix random crash seen while removing driver

This fixes the random kernel crash seen while removing the driver, when running the load/unload test over multiple iterations.

1) modprobe btnxpuart 2) hciconfig hci0 reset 3) hciconfig (check hci0 interface up with valid BD address) 4) modprobe -r btnxpuart Repeat steps 1 to 4

The ps_wakeup() call in btnxpuart_close() schedules the psdata->work(), which gets scheduled after module is removed, causing a kernel crash.

This hidden issue got highlighted after enabling Power Save by default in 4183a7be7700 (Bluetooth: btnxpuart: Enable Power Save feature on startup)

The new ps_cleanup() deasserts UART break immediately while closing serdev device, cancels any scheduled ps_work and destroys the ps_lock mutex.

[ 85.884604] Unable to handle kernel paging request at virtual address ffffd4a61638f258 [ 85.884624] Mem abort info: [ 85.884625] ESR = 0x0000000086000007 [ 85.884628] EC = 0x21: IABT (current EL), IL = 32 bits [ 85.884633] SET = 0, FnV = 0 [ 85.884636] EA = 0, S1PTW = 0 [ 85.884638] FSC = 0x07: level 3 translation fault [ 85.884642] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000041dd0000 [ 85.884646] [ffffd4a61638f258] pgd=1000000095fff003, p4d=1000000095fff003, pud=100000004823d003, pmd=100000004823e003, pte=0000000000000000 [ 85.884662] Internal error: Oops: 0000000086000007 [#1] PREEMPT SMP [ 85.890932] Modules linked in: algif_hash algif_skcipher af_alg overlay fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine authenc libdes crct10dif_ce polyval_ce polyval_generic snd_soc_imx_spdif snd_soc_imx_card snd_soc_ak5558 snd_soc_ak4458 caam secvio error snd_soc_fsl_spdif snd_soc_fsl_micfil snd_soc_fsl_sai snd_soc_fsl_utils gpio_ir_recv rc_core fuse [last unloaded: btnxpuart(O)] [ 85.927297] CPU: 1 PID: 67 Comm: kworker/1:3 Tainted: G O 6.1.36+g937b1be4345a #1 [ 85.936176] Hardware name: FSL i.MX8MM EVK board (DT) [ 85.936182] Workqueue: events 0xffffd4a61638f380 [ 85.936198] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 85.952817] pc : 0xffffd4a61638f258 [ 85.952823] lr : 0xffffd4a61638f258 [ 85.952827] sp : ffff8000084fbd70 [ 85.952829] x29: ffff8000084fbd70 x28: 0000000000000000 x27: 0000000000000000 [ 85.963112] x26: ffffd4a69133f000 x25: ffff4bf1c8540990 x24: ffff4bf215b87305 [ 85.963119] x23: ffff4bf215b87300 x22: ffff4bf1c85409d0 x21: ffff4bf1c8540970 [ 85.977382] x20: 0000000000000000 x19: ffff4bf1c8540880 x18: 0000000000000000 [ 85.977391] x17: 0000000000000000 x16: 0000000000000133 x15: 0000ffffe2217090 [ 85.977399] x14: 0000000000000001 x13: 0000000000000133 x12: 0000000000000139 [ 85.977407] x11: 0000000000000001 x10: 0000000000000a60 x9 : ffff8000084fbc50 [ 85.977417] x8 : ffff4bf215b7d000 x7 : ffff4bf215b83b40 x6 : 00000000000003e8 [ 85.977424] x5 : 00000000410fd030 x4 : 0000000000000000 x3 : 0000000000000000 [ 85.977432] x2 : 0000000000000000 x1 : ffff4bf1c4265880 x0 : 0000000000000000 [ 85.977443] Call trace: [ 85.977446] 0xffffd4a61638f258 [ 85.977451] 0xffffd4a61638f3e8 [ 85.977455] process_one_work+0x1d4/0x330 [ 85.977464] worker_thread+0x6c/0x430 [ 85.977471] kthread+0x108/0x10c [ 85.977476] ret_from_fork+0x10/0x20 [ 85.977488] Code: bad PC value [ 85.977491] ---[ end trace 0000000000000000 ]---

Preset since v6.9.11

Which versions are affected by CVE-2024-46680?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2024-46680?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2024-46680 being exploited?

There is no known exploitation of CVE-2024-46680 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as BELL-CVE-2024-46680, DEBIAN-CVE-2024-46680, GHSA-6mh5-7p3w-gfg6, UBUNTU-CVE-2024-46680.