Subject: CVE-2024-26959: Bluetooth: btnxpuart: Fix btnxpuart_close

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

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

Bluetooth: btnxpuart: Fix btnxpuart_close

Fix scheduling while atomic BUG in btnxpuart_close(), properly
purge the transmit queue and free the receive skb.

[   10.973809] BUG: scheduling while atomic: kworker/u9:0/80/0x00000002
...
[   10.980740] CPU: 3 PID: 80 Comm: kworker/u9:0 Not tainted 6.8.0-rc7-0.0.0-devel-00005-g61fdfceacf09 #1
[   10.980751] Hardware name: Toradex Verdin AM62 WB on Dahlia Board (DT)
[   10.980760] Workqueue: hci0 hci_power_off [bluetooth]
[   10.981169] Call trace:
...
[   10.981363]  uart_update_mctrl+0x58/0x78
[   10.981373]  uart_dtr_rts+0x104/0x114
[   10.981381]  tty_port_shutdown+0xd4/0xdc
[   10.981396]  tty_port_close+0x40/0xbc
[   10.981407]  uart_close+0x34/0x9c
[   10.981414]  ttyport_close+0x50/0x94
[   10.981430]  serdev_device_close+0x40/0x50
[   10.981442]  btnxpuart_close+0x24/0x98 [btnxpuart]
[   10.981469]  hci_dev_close_sync+0x2d8/0x718 [bluetooth]
[   10.981728]  hci_dev_do_close+0x2c/0x70 [bluetooth]
[   10.981862]  hci_power_off+0x20/0x64 [bluetooth]

The Linux kernel CVE team has assigned CVE-2024-26959 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 6.4 with commit 689ca16e5232 and fixed in 6.6.24 with commit d4e2365b07f1
	Issue introduced in 6.4 with commit 689ca16e5232 and fixed in 6.7.12 with commit 586e099c93fe
	Issue introduced in 6.4 with commit 689ca16e5232 and fixed in 6.8.3 with commit 74bcf708775c
	Issue introduced in 6.4 with commit 689ca16e5232 and fixed in 6.9 with commit 664130c0b030

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-26959
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	drivers/bluetooth/btnxpuart.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/d4e2365b07f1ae1f811a915b514caef5b2d6581e
	https://git.kernel.org/stable/c/586e099c93fe26b7bd40593979532f507ed9f6a4
	https://git.kernel.org/stable/c/74bcf708775c405f7fb6ed776ccd3e1957f38a52
	https://git.kernel.org/stable/c/664130c0b0309b360bc5bdd40a30604a9387bde8