Vulnerabilidad en kernel de Linux (CVE-2021-47341)

En el kernel de Linux se ha resuelto la siguiente vulnerabilidad: KVM: mmio: Arreglar use-after-free Leer en kvm_vm_ioctl_unregister_coalesced_mmio BUG: KASAN: use-after-free en kvm_vm_ioctl_unregister_coalesced_mmio+0x7c/0x1ec arch/arm64/kvm/../. ./../virt/kvm/coalesced_mmio.c:183 Lectura de tamaño 8 en la dirección ffff0000c03a2500 por tarea syz-executor083/4269 CPU: 5 PID: 4269 Comm: syz-executor083 Not tainted 5.10.0 #7 Nombre de hardware: linux ,dummy-virt (DT) Seguimiento de llamadas: dump_backtrace+0x0/0x2d0 arch/arm64/kernel/stacktrace.c:132 show_stack+0x28/0x34 arch/arm64/kernel/stacktrace.c:196 __dump_stack lib/dump_stack.c:77 [en línea] dump_stack+0x110/0x164 lib/dump_stack.c:118 print_address_description+0x78/0x5c8 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [en línea] kasan_report+0x148/0x1e4 mm/kasan /report.c:562 check_memory_region_inline mm/kasan/generic.c:183 [en línea] __asan_load8+0xb4/0xbc mm/kasan/generic.c:252 kvm_vm_ioctl_unregister_coalesced_mmio+0x7c/0x1ec arch/arm64/kvm/../../ ../virt/kvm/coalesced_mmio.c:183 kvm_vm_ioctl+0xe30/0x14c4 arch/arm64/kvm/../../../virt/kvm/kvm_main.c:3755 vfs_ioctl fs/ioctl.c:48 [ en línea] __do_sys_ioctl fs/ioctl.c:753 [en línea] __se_sys_ioctl fs/ioctl.c:739 [en línea] __arm64_sys_ioctl+0xf88/0x131c fs/ioctl.c:739 __invoke_syscall arch/arm64/kernel/syscall.c:36 [en línea ] invoke_syscall arch/arm64/kernel/syscall.c:48 [en línea] el0_svc_common arch/arm64/kernel/syscall.c:158 [en línea] do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:220 el0_svc+0x1c /0x28 arch/arm64/kernel/entry-common.c:367 el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383 el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 Asignado por tarea 4269: stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c:48 [en línea] kasan_set_track mm/kasan/common.c:56 [en línea] __kasan_kmalloc+0xdc/0x120 mm/kasan /common.c:461 kasan_kmalloc+0xc/0x14 mm/kasan/common.c:475 kmem_cache_alloc_trace include/linux/slab.h:450 [en línea] kmalloc include/linux/slab.h:552 [en línea] kzalloc include/linux /slab.h:664 [en línea] kvm_vm_ioctl_register_coalesced_mmio+0x78/0x1cc arch/arm64/kvm/../../../virt/kvm/coalesced_mmio.c:146 kvm_vm_ioctl+0x7e8/0x14c4 arch/arm64/kvm/. ./../../virt/kvm/kvm_main.c:3746 vfs_ioctl fs/ioctl.c:48 [en línea] __do_sys_ioctl fs/ioctl.c:753 [en línea] __se_sys_ioctl fs/ioctl.c:739 [en línea] __arm64_sys_ioctl+0xf88/0x131c fs/ioctl.c:739 __invoke_syscall arch/arm64/kernel/syscall.c:36 [en línea] invoke_syscall arch/arm64/kernel/syscall.c:48 [en línea] el0_svc_common arch/arm64/kernel/syscall .c:158 [en línea] do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:220 el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367 el0_sync_handler+0x98/0x170 arch/arm64/ kernel/entry-common.c:383 el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 Liberado por la tarea 4269: stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c :48 [en línea] kasan_set_track+0x38/0x6c mm/kasan/common.c:56 kasan_set_free_info+0x20/0x40 mm/kasan/generic.c:355 __kasan_slab_free+0x124/0x150 mm/kasan/common.c:422 kasan_slab_free+0x10 /0x1c mm/kasan/common.c:431 slab_free_hook mm/slub.c:1544 [en línea] slab_free_freelist_hook mm/slub.c:1577 [en línea] slab_free mm/slub.c:3142 [en línea] kfree+0x104/0x38c mm /slub.c:4124 coalesced_mmio_destructor+0x94/0xa4 arch/arm64/kvm/../../../virt/kvm/coalesced_mmio.c:102 kvm_iodevice_destructor include/kvm/iodev.h:61 [en línea] kvm_io_bus_unregister_dev+ 0x248/0x280 arch/arm64/kvm/../../../virt/kvm/kvm_main.c:4374 kvm_vm_ioctl_unregister_coalesced_mmio+0x158/0x1ec arch/arm64/kvm/../../../virt/kvm /coalesced_mmio.c:186 kvm_vm_ioctl+0xe30/0x14c4 arch/arm64/kvm/../../../virt/kvm/kvm_main.c:3755 vfs_ioctl fs/ioctl.c:48 [en línea] __do_sys_ioctl fs/ioctl .c:753 [en línea] __se_sys_ioctl fs/ioctl.c:739 ---truncado---