CVE-2026-64468
Description
In the Linux kernel, the following vulnerability has been resolved:
binder: fix UAF in binder_free_transaction()
In binder_free_transaction(), the t->to_proc is read under the t->lock.
However, once the t->lock is dropped, the to_proc can die in parallel.
This leads to a use-after-free error when we attempt to acquire its
inner lock right afterwards:
==================================================================
BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x1a0
Write of size 4 at addr ffff00001125da70 by task B/672
CPU: 20 UID: 0 PID: 672 Comm: B Not tainted 7.1.0-rc6-00284-g8e65320d91cd #4 PREEMPT
Hardware name: linux,dummy-virt (DT)
Call trace:
_raw_spin_lock+0xe4/0x1a0
binder_free_transaction+0x8c/0x320
binder_send_failed_reply+0x21c/0x2f8
binder_thread_release+0x488/0x7e0
binder_ioctl+0x12c0/0x29a0
[...]
Allocated by task 675:
__kmalloc_cache_noprof+0x174/0x444
binder_open+0x118/0xb70
do_dentry_open+0x374/0x1040
vfs_open+0x58/0x3bc
[...]
Freed by task 212:
__kasan_slab_free+0x58/0x80
kfree+0x1a0/0x4a4
binder_proc_dec_tmpref+0x32c/0x5e0
binder_deferred_func+0xc48/0x104c
process_one_work+0x53c/0xbc0
[...]
==================================================================
To prevent this, pin the target thread (t->to_thread) to guarantee the
target process remains alive. Undelivered transactions without a target
thread are already safe, as the target process can only be the current
context in those paths.
Metadata
Severity & Metrics
No CVSS data available.
Affected products (2)
| Vendor | Product | Platform | Versions |
|---|---|---|---|
| Linux | Linux | — | a370003cc301d4361bae20c9ef615f89bf8d1e8a < 5602a43f251c3d75312df91a422675fc00ca3dce, a370003cc301d4361bae20c9ef615f89bf8d1e8a < 0be901ab1dcc4af59b88f2e324493bb283850167, a370003cc301d4361bae20c9ef615f89bf8d1e8a < 48aeda9f8039e4a6971d1804578efde7f2c01eda, a370003cc301d4361bae20c9ef615f89bf8d1e8a < 45df558c543bb5543bacc8065fd7c567740781e5 … |
| Linux | Linux | — | 5.2, 0 < 5.2, 5.10.261 ≤ 5.10.*, 5.15.212 ≤ 5.15.* … |
References (8)
- https://git.kernel.org/stable/c/5602a43f251c3d75312df91a422675fc00ca3dce
- https://git.kernel.org/stable/c/0be901ab1dcc4af59b88f2e324493bb283850167
- https://git.kernel.org/stable/c/48aeda9f8039e4a6971d1804578efde7f2c01eda
- https://git.kernel.org/stable/c/45df558c543bb5543bacc8065fd7c567740781e5
- https://git.kernel.org/stable/c/d45ef513eed1abebfec90c3cfb6ae50c2a4182db
- https://git.kernel.org/stable/c/328ccf32acb87e8bbb1fe2b065068c574e4db2bf
- https://git.kernel.org/stable/c/0f15f0f6ca5df566275ce517f257af2559528b41
- https://git.kernel.org/stable/c/f223d27a546c1e1f48d38fd67760e78f068fe8c4