================================================================== BUG: KASAN: slab-use-after-free in handle_mm_fault+0x14f0/0x19a0 mm/memory.c:5835 Read of size 8 at addr ffff88807c445210 by task syz.2.819/8879 CPU: 0 UID: 0 PID: 8879 Comm: syz.2.819 Not tainted 6.10.0-next-20240717-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 handle_mm_fault+0x14f0/0x19a0 mm/memory.c:5835 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f5e1e4393aa Code: 90 8b 45 04 ba 03 00 00 00 c1 e0 04 03 45 64 39 c6 48 0f 42 f0 45 31 c9 31 ff e8 21 c7 13 00 8b 75 00 ba 03 00 00 00 45 89 e0 <49> 89 45 00 41 b9 00 00 00 10 b9 01 80 00 00 31 ff c1 e6 06 e8 fd RSP: 002b:00007f5e1f360fe0 EFLAGS: 00010217 RAX: ffffffffffffffff RBX: 00007f5e1e704038 RCX: 00007f5e1e575ad3 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000020000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000008001 R11: 0000000000000246 R12: ffffffffffffffff R13: 0000000020c57000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 5114: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044 vm_area_dup+0x27/0x290 kernel/fork.c:487 dup_mmap kernel/fork.c:696 [inline] dup_mm kernel/fork.c:1674 [inline] copy_mm+0xc7b/0x1f30 kernel/fork.c:1723 copy_process+0x186b/0x3d90 kernel/fork.c:2376 kernel_clone+0x226/0x8f0 kernel/fork.c:2788 __do_sys_clone kernel/fork.c:2931 [inline] __se_sys_clone kernel/fork.c:2915 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2915 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 0: 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:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4548 rcu_do_batch kernel/rcu/tree.c:2569 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2843 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:3106 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210 vma_complete+0x98a/0xb60 mm/mmap.c:609 vma_merge+0x1d9b/0x2690 mm/mmap.c:1079 vma_modify+0xb8/0x350 mm/mmap.c:2565 vma_modify_flags_uffd include/linux/mm.h:3352 [inline] userfaultfd_release+0x413/0x900 fs/userfaultfd.c:907 __fput+0x24a/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:222 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807c4451f0 which belongs to the cache vm_area_struct of size 184 The buggy address is located 32 bytes inside of freed 184-byte region [ffff88807c4451f0, ffff88807c4452a8) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c445 memcg:ffff88801e421901 ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xfdffffff(slab) raw: 00fff00000000000 ffff888015eefb40 ffffea0000b3bd40 dead000000000007 raw: 0000000000000000 0000000000100010 00000001fdffffff ffff88801e421901 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4557, tgid 4557 (udevd), ts 34732711255, free_ts 34428255013 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1492 prep_new_page mm/page_alloc.c:1500 [inline] get_page_from_freelist+0x2ccb/0x2d80 mm/page_alloc.c:3473 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4731 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2321 allocate_slab+0x5a/0x2f0 mm/slub.c:2484 new_slab mm/slub.c:2537 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3723 __slab_alloc+0x58/0xa0 mm/slub.c:3813 __slab_alloc_node mm/slub.c:3866 [inline] slab_alloc_node mm/slub.c:4025 [inline] kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4044 vm_area_dup+0x27/0x290 kernel/fork.c:487 dup_mmap kernel/fork.c:696 [inline] dup_mm kernel/fork.c:1674 [inline] copy_mm+0xc7b/0x1f30 kernel/fork.c:1723 copy_process+0x186b/0x3d90 kernel/fork.c:2376 kernel_clone+0x226/0x8f0 kernel/fork.c:2788 __do_sys_clone kernel/fork.c:2931 [inline] __se_sys_clone kernel/fork.c:2915 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2915 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 page last free pid 4555 tgid 4555 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1093 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2643 discard_slab mm/slub.c:2583 [inline] __put_partials+0xeb/0x130 mm/slub.c:3051 put_cpu_partial+0x17c/0x250 mm/slub.c:3126 __slab_free+0x2ea/0x3d0 mm/slub.c:4343 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:664 netlink_sendmsg+0x638/0xcb0 net/netlink/af_netlink.c:1876 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680 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 Memory state around the buggy address: ffff88807c445100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807c445180: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fa fb >ffff88807c445200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c445280: fb fb fb fb fb fc fc fc fc fc fc fc fc 00 00 00 ffff88807c445300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================