================================================================== BUG: KASAN: slab-use-after-free in vma_multi_allowed+0x172/0x1b0 Read of size 8 at addr ffff888033c15cd8 by task syz-executor.0/79727 CPU: 0 UID: 0 PID: 79727 Comm: syz-executor.0 Not tainted 6.17.0-rc1-next-20250813 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0xca/0x120 print_report+0xcb/0x610 kasan_report+0xca/0x100 vma_multi_allowed+0x172/0x1b0 __do_sys_mremap+0xcb7/0x1410 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8853aaeb19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8851024188 EFLAGS: 00000246 ORIG_RAX: 0000000000000019 RAX: ffffffffffffffda RBX: 00007f8853bc1f60 RCX: 00007f8853aaeb19 RDX: 0000000000002000 RSI: 0000000000002000 RDI: 0000000020cb7000 RBP: 00007f8853b08f6d R08: 0000000020eb3000 R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff8f7a562f R14: 00007f8851024300 R15: 0000000000022000 kernel write not supported for file /diskstats (pid: 62 comm: kworker/1:2) SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=79733 comm=syz-executor.2 Allocated by task 79727: SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=79733 comm=syz-executor.2 kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc_noprof+0x13c/0x3d0 vm_area_dup+0x25/0x6f0 __split_vma+0x179/0xde0 vms_gather_munmap_vmas+0x340/0xc70 do_vmi_align_munmap+0x25b/0x550 do_vmi_munmap+0x1eb/0x3c0 __vm_munmap+0x190/0x370 __x64_sys_munmap+0x59/0x80 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 79724: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 __kasan_save_free_info+0x3a/0x60 __kasan_slab_free+0x3f/0x50 slab_free_after_rcu_debug+0xd6/0x290 rcu_core+0x7c8/0x1800 handle_softirqs+0x1b1/0x770 __irq_exit_rcu+0xc4/0x100 irq_exit_rcu+0x9/0x20 sysvec_apic_timer_interrupt+0x70/0x80 asm_sysvec_apic_timer_interrupt+0x1a/0x20 Last potentially related work creation: kasan_save_stack+0x24/0x50 kasan_record_aux_stack+0x89/0xa0 kmem_cache_free+0x145/0x460 vms_complete_munmap_vmas+0x549/0x9f0 do_vmi_align_munmap+0x3db/0x550 do_vmi_munmap+0x1eb/0x3c0 do_munmap+0xbd/0x100 mremap_to+0x242/0x450 __do_sys_mremap+0xca2/0x1410 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888033c15c80 which belongs to the cache vm_area_struct of size 256 The buggy address is located 88 bytes inside of freed 256-byte region [ffff888033c15c80, ffff888033c15d80) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33c15 memcg:ffff8880506c1381 flags: 0x100000000000000(node=0|zone=1) page_type: f5(slab) raw: 0100000000000000 ffff888008fffc80 dead000000000122 0000000000000000 raw: 0000000000000000 00000000000c000c 00000000f5000000 ffff8880506c1381 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888033c15b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888033c15c00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc >ffff888033c15c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888033c15d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888033c15d80: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ================================================================== kernel write not supported for file /diskstats (pid: 126 comm: kworker/0:3) kernel write not supported for file /diskstats (pid: 62 comm: kworker/1:2) SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=79747 comm=syz-executor.2 kernel write not supported for file /diskstats (pid: 59831 comm: kworker/0:1) kernel write not supported for file /diskstats (pid: 62 comm: kworker/1:2) SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=79759 comm=syz-executor.2 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=79773 comm=syz-executor.2 Bluetooth: hci3: command 0x0c1a tx timeout loop0: detected capacity change from 0 to 3520 loop0: detected capacity change from 0 to 3520 loop0: detected capacity change from 0 to 3520 loop0: detected capacity change from 0 to 3520 Bluetooth: hci3: command 0x0c1a tx timeout UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 misc raw-gadget: fail, usb_gadget_register_driver returned -16 audit: type=1400 audit(2000000318.520:83): avc: denied { watch_reads } for pid=82094 comm="syz-executor.0" path="/syzkaller-testdir462873427/syzkaller.xLU7d4/1094/file0" dev="sda" ino=16103 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=file permissive=1 UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy program syz-executor.4 is using a deprecated SCSI ioctl, please convert it to SG_IO misc raw-gadget: fail, usb_gadget_register_driver returned -16 program syz-executor.4 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.1 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.1 is using a deprecated SCSI ioctl, please convert it to SG_IO UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 program syz-executor.1 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.6 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.4 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.4 is using a deprecated SCSI ioctl, please convert it to SG_IO program syz-executor.6 is using a deprecated SCSI ioctl, please convert it to SG_IO