CVE-2024-54460

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

Bluetooth: iso: Fix circular lock in isolistenbis

This fixes the circular locking dependency warning below, by releasing the socket lock before enterning isolistenbis, to avoid any potential deadlock with hdev lock.

[ 75.307983] ====================================================== [ 75.307984] WARNING: possible circular locking dependency detected [ 75.307985] 6.12.0-rc6+ #22 Not tainted [ 75.307987] ------------------------------------------------------ [ 75.307987] kworker/u81:2/2623 is trying to acquire lock: [ 75.307988] ffff8fde1769da58 (sklock-AFBLUETOOTH-BTPROTOISO) at: isoconnectcfm+0x253/0x840 [bluetooth] [ 75.308021] but task is already holding lock: [ 75.308022] ffff8fdd61a10078 (&hdev->lock) at: hcileperadvreportevt+0x47/0x2f0 [bluetooth] [ 75.308053] which lock already depends on the new lock.

[ 75.308054] the existing dependency chain (in reverse order) is: [ 75.308055] -> #1 (&hdev->lock){+.+.}-{3:3}: [ 75.308057] __mutexlock+0xad/0xc50 [ 75.308061] mutexlock_nested+0x1b/0x30 [ 75.308063] isosocklisten+0x143/0x5c0 [bluetooth] [ 75.308085] __syslistensocket+0x49/0x60 [ 75.308088] __x64syslisten+0x4c/0x90 [ 75.308090] x64syscall+0x2517/0x25f0 [ 75.308092] dosyscall64+0x87/0x150 [ 75.308095] entrySYSCALL64afterhwframe+0x76/0x7e [ 75.308098] -> #0 (sklock-AFBLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}: [ 75.308100] __lockacquire+0x155e/0x25f0 [ 75.308103] lockacquire+0xc9/0x300 [ 75.308105] locksocknested+0x32/0x90 [ 75.308107] isoconnectcfm+0x253/0x840 [bluetooth] [ 75.308128] hciconnectcfm+0x6c/0x190 [bluetooth] [ 75.308155] hcileperadvreportevt+0x27b/0x2f0 [bluetooth] [ 75.308180] hcilemetaevt+0xe7/0x200 [bluetooth] [ 75.308206] hcieventpacket+0x21f/0x5c0 [bluetooth] [ 75.308230] hcirxwork+0x3ae/0xb10 [bluetooth] [ 75.308254] processonework+0x212/0x740 [ 75.308256] workerthread+0x1bd/0x3a0 [ 75.308258] kthread+0xe4/0x120 [ 75.308259] retfromfork+0x44/0x70 [ 75.308261] retfromforkasm+0x1a/0x30 [ 75.308263] other info that might help us debug this:

[ 75.308264] Possible unsafe locking scenario:

[ 75.308264] CPU0 CPU1 [ 75.308265] ---- ---- [ 75.308265] lock(&hdev->lock); [ 75.308267] lock(sklock- AFBLUETOOTH-BTPROTOISO); [ 75.308268] lock(&hdev->lock); [ 75.308269] lock(sklock-AFBLUETOOTH-BTPROTOISO); [ 75.308270] *** DEADLOCK ***

[ 75.308271] 4 locks held by kworker/u81:2/2623: [ 75.308272] #0: ffff8fdd66e52148 ((wqcompletion)hci0#2){+.+.}-{0:0}, at: processonework+0x443/0x740 [ 75.308276] #1: ffffafb488b7fe48 ((workcompletion)(&hdev->rxwork)), at: processonework+0x1ce/0x740 [ 75.308280] #2: ffff8fdd61a10078 (&hdev->lock){+.+.}-{3:3} at: hcileperadvreportevt+0x47/0x2f0 [bluetooth] [ 75.308304] #3: ffffffffb6ba4900 (rcureadlock){....}-{1:2}, at: hciconnectcfm+0x29/0x190 [bluetooth]