CVE-2024-46788

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> tracing/osnoise: Use a cpumask to know what threads are kthreads<br /> <br /> The start_kthread() and stop_thread() code was not always called with the<br /> interface_lock held. This means that the kthread variable could be<br /> unexpectedly changed causing the kthread_stop() to be called on it when it<br /> should not have been, leading to:<br /> <br /> while true; do<br /> rtla timerlat top -u -q &amp; PID=$!;<br /> sleep 5;<br /> kill -INT $PID;<br /> sleep 0.001;<br /> kill -TERM $PID;<br /> wait $PID;<br /> done<br /> <br /> Causing the following OOPS:<br /> <br /> Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN PTI<br /> KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]<br /> CPU: 5 UID: 0 PID: 885 Comm: timerlatu/5 Not tainted 6.11.0-rc4-test-00002-gbc754cc76d1b-dirty #125 a533010b71dab205ad2f507188ce8c82203b0254<br /> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014<br /> RIP: 0010:hrtimer_active+0x58/0x300<br /> Code: 48 c1 ee 03 41 54 48 01 d1 48 01 d6 55 53 48 83 ec 20 80 39 00 0f 85 30 02 00 00 49 8b 6f 30 4c 8d 75 10 4c 89 f0 48 c1 e8 03 b6 3c 10 4c 89 f0 83 e0 07 83 c0 03 40 38 f8 7c 09 40 84 ff 0f<br /> RSP: 0018:ffff88811d97f940 EFLAGS: 00010202<br /> RAX: 0000000000000002 RBX: ffff88823c6b5b28 RCX: ffffed10478d6b6b<br /> RDX: dffffc0000000000 RSI: ffffed10478d6b6c RDI: ffff88823c6b5b28<br /> RBP: 0000000000000000 R08: ffff88823c6b5b58 R09: ffff88823c6b5b60<br /> R10: ffff88811d97f957 R11: 0000000000000010 R12: 00000000000a801d<br /> R13: ffff88810d8b35d8 R14: 0000000000000010 R15: ffff88823c6b5b28<br /> FS: 0000000000000000(0000) GS:ffff88823c680000(0000) knlGS:0000000000000000<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 0000561858ad7258 CR3: 000000007729e001 CR4: 0000000000170ef0<br /> Call Trace:<br /> <br /> ? die_addr+0x40/0xa0<br /> ? exc_general_protection+0x154/0x230<br /> ? asm_exc_general_protection+0x26/0x30<br /> ? hrtimer_active+0x58/0x300<br /> ? __pfx_mutex_lock+0x10/0x10<br /> ? __pfx_locks_remove_file+0x10/0x10<br /> hrtimer_cancel+0x15/0x40<br /> timerlat_fd_release+0x8e/0x1f0<br /> ? security_file_release+0x43/0x80<br /> __fput+0x372/0xb10<br /> task_work_run+0x11e/0x1f0<br /> ? _raw_spin_lock+0x85/0xe0<br /> ? __pfx_task_work_run+0x10/0x10<br /> ? poison_slab_object+0x109/0x170<br /> ? do_exit+0x7a0/0x24b0<br /> do_exit+0x7bd/0x24b0<br /> ? __pfx_migrate_enable+0x10/0x10<br /> ? __pfx_do_exit+0x10/0x10<br /> ? __pfx_read_tsc+0x10/0x10<br /> ? ktime_get+0x64/0x140<br /> ? _raw_spin_lock_irq+0x86/0xe0<br /> do_group_exit+0xb0/0x220<br /> get_signal+0x17ba/0x1b50<br /> ? vfs_read+0x179/0xa40<br /> ? timerlat_fd_read+0x30b/0x9d0<br /> ? __pfx_get_signal+0x10/0x10<br /> ? __pfx_timerlat_fd_read+0x10/0x10<br /> arch_do_signal_or_restart+0x8c/0x570<br /> ? __pfx_arch_do_signal_or_restart+0x10/0x10<br /> ? vfs_read+0x179/0xa40<br /> ? ksys_read+0xfe/0x1d0<br /> ? __pfx_ksys_read+0x10/0x10<br /> syscall_exit_to_user_mode+0xbc/0x130<br /> do_syscall_64+0x74/0x110<br /> ? __pfx___rseq_handle_notify_resume+0x10/0x10<br /> ? __pfx_ksys_read+0x10/0x10<br /> ? fpregs_restore_userregs+0xdb/0x1e0<br /> ? fpregs_restore_userregs+0xdb/0x1e0<br /> ? syscall_exit_to_user_mode+0x116/0x130<br /> ? do_syscall_64+0x74/0x110<br /> ? do_syscall_64+0x74/0x110<br /> ? do_syscall_64+0x74/0x110<br /> entry_SYSCALL_64_after_hwframe+0x71/0x79<br /> RIP: 0033:0x7ff0070eca9c<br /> Code: Unable to access opcode bytes at 0x7ff0070eca72.<br /> RSP: 002b:00007ff006dff8c0 EFLAGS: 00000246 ORIG_RAX: 0000000000000000<br /> RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007ff0070eca9c<br /> RDX: 0000000000000400 RSI: 00007ff006dff9a0 RDI: 0000000000000003<br /> RBP: 00007ff006dffde0 R08: 0000000000000000 R09: 00007ff000000ba0<br /> R10: 00007ff007004b08 R11: 0000000000000246 R12: 0000000000000003<br /> R13: 00007ff006dff9a0 R14: 0000000000000007 R15: 0000000000000008<br /> <br /> Modules linked in: snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hwdep snd_hda_core<br /> ---[ end trace 0000000000000000 ]---<br /> <br /> This is because it would mistakenly call kthread_stop() on a user space<br /> thread making it "exit" before it actually exits.<br /> <br /> Since kthread<br /> ---truncated---