CVE-2024-53208

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

Bluetooth: MGMT: Fix slab-use-after-free Read in set_powered_sync

This fixes the following crash:

================================================================== BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353 Read of size 8 at addr ffff888029b4dd18 by task kworker/u9:0/54

CPU: 1 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.11.0-rc6-syzkaller-01155-gf723224742fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: hci0 hci_cmd_sync_work Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 q kasan_report+0x143/0x180 mm/kasan/report.c:601 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:328 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Allocated by task 5247: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4193 kmalloc_noprof include/linux/slab.h:681 [inline] kzalloc_noprof include/linux/slab.h:807 [inline] mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1394 hci_mgmt_cmd+0xc47/0x11d0 net/bluetooth/hci_sock.c:1712 hci_sock_sendmsg+0x7b8/0x11c0 net/bluetooth/hci_sock.c:1832 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5246: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2256 [inline] slab_free mm/slub.c:4477 [inline] kfree+0x149/0x360 mm/slub.c:4598 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1443 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259 __mgmt_power_off+0x112/0x420 net/bluetooth/mgmt.c:9455 hci_dev_close_sync+0x665/0x11a0 net/bluetooth/hci_sync.c:5191 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_dev_close+0x112/0x210 net/bluetooth/hci_core.c:508 sock_do_ioctl+0x158/0x460 net/socket.c:1222 sock_ioctl+0x629/0x8e0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83gv entry_SYSCALL_64_after_hwframe+0x77/0x7f

Weakness

Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.

Affected Software

Extended Description

The use of previously-freed memory can have any number of adverse consequences, ranging from the corruption of valid data to the execution of arbitrary code, depending on the instantiation and timing of the flaw. The simplest way data corruption may occur involves the system’s reuse of the freed memory. Use-after-free errors have two common and sometimes overlapping causes:

In this scenario, the memory in question is allocated to another pointer validly at some point after it has been freed. The original pointer to the freed memory is used again and points to somewhere within the new allocation. As the data is changed, it corrupts the validly used memory; this induces undefined behavior in the process. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.

Potential Mitigations

References

• https://git.kernel.org/stable/c/0b882940665ca2849386ee459d4331aa2f8c4e7d
• https://git.kernel.org/stable/c/6b75f32bce90c085c89c45761373d940fdcff68c
• https://git.kernel.org/stable/c/87819234aa1d2a0cb0f962fabb335e798f5ec8b2
• https://git.kernel.org/stable/c/95f7a972194ad20696c36523b54c19a3567e0697
• https://git.kernel.org/stable/c/cdfc818ffdfeb8266351ed59b6d884056009a095