Description

In the Linux kernel, the following vulnerability has been resolved: usb: typec: altmode should keep reference to parent The altmode device release refers to its parent device, but without keeping a reference to it. When registering the altmode, get a reference to the parent and put it in the release function. Before this fix, when using CONFIG_DEBUG_KOBJECT_RELEASE, we see issues like this: [ 43.572860] kobject: 'port0.0' (ffff8880057ba008): kobject_release, parent 0000000000000000 (delayed 3000) [ 43.573532] kobject: 'port0.1' (ffff8880057bd008): kobject_release, parent 0000000000000000 (delayed 1000) [ 43.574407] kobject: 'port0' (ffff8880057b9008): kobject_release, parent 0000000000000000 (delayed 3000) [ 43.575059] kobject: 'port1.0' (ffff8880057ca008): kobject_release, parent 0000000000000000 (delayed 4000) [ 43.575908] kobject: 'port1.1' (ffff8880057c9008): kobject_release, parent 0000000000000000 (delayed 4000) [ 43.576908] kobject: 'typec' (ffff8880062dbc00): kobject_release, parent 0000000000000000 (delayed 4000) [ 43.577769] kobject: 'port1' (ffff8880057bf008): kobject_release, parent 0000000000000000 (delayed 3000) [ 46.612867] ================================================================== [ 46.613402] BUG: KASAN: slab-use-after-free in typec_altmode_release+0x38/0x129 [ 46.614003] Read of size 8 at addr ffff8880057b9118 by task kworker/2:1/48 [ 46.614538] [ 46.614668] CPU: 2 UID: 0 PID: 48 Comm: kworker/2:1 Not tainted 6.12.0-rc1-00138-gedbae730ad31 #535 [ 46.615391] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 [ 46.616042] Workqueue: events kobject_delayed_cleanup [ 46.616446] Call Trace: [ 46.616648] <TASK> [ 46.616820] dump_stack_lvl+0x5b/0x7c [ 46.617112] ? typec_altmode_release+0x38/0x129 [ 46.617470] print_report+0x14c/0x49e [ 46.617769] ? rcu_read_unlock_sched+0x56/0x69 [ 46.618117] ? __virt_addr_valid+0x19a/0x1ab [ 46.618456] ? kmem_cache_debug_flags+0xc/0x1d [ 46.618807] ? typec_altmode_release+0x38/0x129 [ 46.619161] kasan_report+0x8d/0xb4 [ 46.619447] ? typec_altmode_release+0x38/0x129 [ 46.619809] ? process_scheduled_works+0x3cb/0x85f [ 46.620185] typec_altmode_release+0x38/0x129 [ 46.620537] ? process_scheduled_works+0x3cb/0x85f [ 46.620907] device_release+0xaf/0xf2 [ 46.621206] kobject_delayed_cleanup+0x13b/0x17a [ 46.621584] process_scheduled_works+0x4f6/0x85f [ 46.621955] ? __pfx_process_scheduled_works+0x10/0x10 [ 46.622353] ? hlock_class+0x31/0x9a [ 46.622647] ? lock_acquired+0x361/0x3c3 [ 46.622956] ? move_linked_works+0x46/0x7d [ 46.623277] worker_thread+0x1ce/0x291 [ 46.623582] ? __kthread_parkme+0xc8/0xdf [ 46.623900] ? __pfx_worker_thread+0x10/0x10 [ 46.624236] kthread+0x17e/0x190 [ 46.624501] ? kthread+0xfb/0x190 [ 46.624756] ? __pfx_kthread+0x10/0x10 [ 46.625015] ret_from_fork+0x20/0x40 [ 46.625268] ? __pfx_kthread+0x10/0x10 [ 46.625532] ret_from_fork_asm+0x1a/0x30 [ 46.625805] </TASK> [ 46.625953] [ 46.626056] Allocated by task 678: [ 46.626287] kasan_save_stack+0x24/0x44 [ 46.626555] kasan_save_track+0x14/0x2d [ 46.626811] __kasan_kmalloc+0x3f/0x4d [ 46.627049] __kmalloc_noprof+0x1bf/0x1f0 [ 46.627362] typec_register_port+0x23/0x491 [ 46.627698] cros_typec_probe+0x634/0xbb6 [ 46.628026] platform_probe+0x47/0x8c [ 46.628311] really_probe+0x20a/0x47d [ 46.628605] device_driver_attach+0x39/0x72 [ 46.628940] bind_store+0x87/0xd7 [ 46.629213] kernfs_fop_write_iter+0x1aa/0x218 [ 46.629574] vfs_write+0x1d6/0x29b [ 46.629856] ksys_write+0xcd/0x13b [ 46.630128] do_syscall_64+0xd4/0x139 [ 46.630420] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 46.630820] [ 46.630946] Freed by task 48: [ 46.631182] kasan_save_stack+0x24/0x44 [ 46.631493] kasan_save_track+0x14/0x2d [ 46.631799] kasan_save_free_info+0x3f/0x4d [ 46.632144] __kasan_slab_free+0x37/0x45 [ 46.632474] ---truncated---

Metrics

 

CVSS Version 4.0 CVSS Version 3.x CVSS Version 2.0

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.

CVSS 4.0 Severity and Vector Strings:

NIST: NVD

N/A

NVD assessment not yet provided.

CVSS 3.x Severity and Vector Strings:

NIST: NVD

Base Score:  N/A

NVD assessment not yet provided.

CVSS 2.0 Severity and Vector Strings:

NIST: NVD

Base Score: N/A

NVD assessment not yet provided.

kernel.org https://git.kernel.org/stable/c/2b0b33e8a58388fa9078f0fbe9af1900e6b08879 [No types assigned]

kernel.org https://git.kernel.org/stable/c/2c15c4133d00f5da632fce60ed013fc31aa9aa58 [No types assigned]

kernel.org https://git.kernel.org/stable/c/6af43ec3bf40f8b428d9134ffa7a291aecd60da8 [No types assigned]

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

usb: typec: altmode should keep reference to parent

The altmode device release refers to its parent device, but without keeping
a reference to it.

When registering the altmode, get a reference to the parent and put it in
the release function.

Before this fix, when using CONFIG_DEBUG_KOBJECT_RELEASE, we see issues
like this:

[   43.572860] kobject: 'port0.0' (ffff8880057ba008): kobject_release, parent 0000000000000000 (delay

kernel.org https://git.kernel.org/stable/c/1ded6b12499e6dee9b0e1ceac633be36538f6fc2 [No types assigned]

kernel.org https://git.kernel.org/stable/c/68a7c7fe322546be1464174c8d85874b8161deda [No types assigned]

kernel.org https://git.kernel.org/stable/c/87474406056891e4fdea0794e1f632b21b3dfa27 [No types assigned]

kernel.org https://git.kernel.org/stable/c/bee1b68cb8bcee4fd3a8bde3a4886e0b1375dc4d [No types assigned]

kernel.org https://git.kernel.org/stable/c/befab3a278c59db0cc88c8799638064f6d3fd6f8 [No types assigned]