================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_write include/linux/instrumented.h:82 [inline] BUG: KASAN: slab-use-after-free in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] BUG: KASAN: slab-use-after-free in cpumask_clear_cpu include/linux/cpumask.h:628 [inline] BUG: KASAN: slab-use-after-free in flush_tlb_func+0x23d/0x6c0 arch/x86/mm/tlb.c:1132 Write of size 8 at addr ffff88807ed44a80 by task pool_workqueue_/3 CPU: 1 UID: 0 PID: 3 Comm: pool_workqueue_ Not tainted 6.16.0-rc4-next-20250702-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189 instrument_atomic_write include/linux/instrumented.h:82 [inline] clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] cpumask_clear_cpu include/linux/cpumask.h:628 [inline] flush_tlb_func+0x23d/0x6c0 arch/x86/mm/tlb.c:1132 csd_do_func kernel/smp.c:134 [inline] __flush_smp_call_function_queue+0x370/0xaa0 kernel/smp.c:540 __sysvec_call_function_single+0xa8/0x3d0 arch/x86/kernel/smp.c:271 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline] sysvec_call_function_single+0x9e/0xc0 arch/x86/kernel/smp.c:266 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709 RIP: 0010:preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:7019 Code: 24 20 f6 44 24 21 02 74 0c 90 0f 0b 48 f7 03 08 00 00 00 74 64 bf 01 00 00 00 e8 cb bf 18 f6 e8 f6 f0 4f f6 fb bf 01 00 00 00 1b ab ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24 RSP: 0018:ffffc90000087aa0 EFLAGS: 00000286 RAX: c1589c4b05ffda00 RBX: 0000000000000000 RCX: c1589c4b05ffda00 RDX: 0000000000000000 RSI: ffffffff8da6993f RDI: 0000000000000001 RBP: ffffc90000087b40 R08: ffffffff8fc29e37 R09: 1ffffffff1f853c6 R10: dffffc0000000000 R11: fffffbfff1f853c7 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000010f54 irqentry_exit+0x6f/0x90 kernel/entry/common.c:196 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lockdep_unregister_key+0x2c5/0x310 kernel/locking/lockdep.c:6619 Code: 65 48 8b 05 1d a3 25 11 48 3b 44 24 10 0f 84 26 fe ff ff e8 4d 8e d8 09 e8 78 8f d8 09 41 f7 c7 00 02 00 00 74 bd fb 40 84 ed <75> bc eb cd 90 0f 0b 90 e9 19 ff ff ff 90 0f 0b 90 e9 2a ff ff ff RSP: 0018:ffffc90000087c00 EFLAGS: 00000246 RAX: c1589c4b05ffda00 RBX: ffff8880434f7138 RCX: c1589c4b05ffda00 RDX: ffffffff93876358 RSI: ffffffff8da7d37d RDI: ffffffff8be4b100 RBP: ffff8880434f7100 R08: 0000000000000000 R09: ffffffff81aafe18 R10: dffffc0000000000 R11: fffffbfff1f853c7 R12: 0000000000000000 R13: 0000000000001000 R14: 0000000000000001 R15: 0000000000000203 wq_unregister_lockdep kernel/workqueue.c:4819 [inline] pwq_release_workfn+0x6d5/0x870 kernel/workqueue.c:5115 kthread_worker_fn+0x507/0xb60 kernel/kthread.c:1009 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 14651: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 dup_mm kernel/fork.c:1466 [inline] copy_mm+0xdb/0x4b0 kernel/fork.c:1528 copy_process+0x1706/0x3c00 kernel/fork.c:2168 kernel_clone+0x21e/0x870 kernel/fork.c:2598 __do_sys_clone kernel/fork.c:2741 [inline] __se_sys_clone kernel/fork.c:2725 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2725 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 18299: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4782 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 __do_sys_exit_group kernel/exit.c:1111 [inline] __se_sys_exit_group kernel/exit.c:1109 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1109 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807ed44080 which belongs to the cache mm_struct of size 2584 The buggy address is located 2560 bytes inside of freed 2584-byte region [ffff88807ed44080, ffff88807ed44a98) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807ed40000 pfn:0x7ed40 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff8880786e0001 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a84bb40 ffffea000086a400 dead000000000003 raw: ffff88807ed40000 00000000800b000a 00000000f5000000 ffff8880786e0001 head: 00fff00000000040 ffff88801a84bb40 ffffea000086a400 dead000000000003 head: ffff88807ed40000 00000000800b000a 00000000f5000000 ffff8880786e0001 head: 00fff00000000003 ffffea0001fb5001 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5499, tgid 5499 (dhcpcd), ts 71194135877, free_ts 71080745850 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1848 prep_new_page mm/page_alloc.c:1856 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3855 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5145 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4236 dup_mm kernel/fork.c:1466 [inline] copy_mm+0xdb/0x4b0 kernel/fork.c:1528 copy_process+0x1706/0x3c00 kernel/fork.c:2168 kernel_clone+0x21e/0x870 kernel/fork.c:2598 __do_sys_clone kernel/fork.c:2741 [inline] __se_sys_clone kernel/fork.c:2725 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2725 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5759 tgid 5759 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1392 [inline] __free_frozen_pages+0xb80/0xd80 mm/page_alloc.c:2892 __folio_put+0x21b/0x2c0 mm/swap.c:112 put_netmem net/core/skbuff.c:7372 [inline] skb_page_unref include/linux/skbuff_ref.h:43 [inline] __skb_frag_unref include/linux/skbuff_ref.h:56 [inline] skb_release_data+0x49a/0x7c0 net/core/skbuff.c:1081 skb_release_all net/core/skbuff.c:1152 [inline] __napi_kfree_skb net/core/skbuff.c:1442 [inline] kfree_skb_napi_cache net/core/skbuff.c:7168 [inline] skb_attempt_defer_free+0x422/0x5c0 net/core/skbuff.c:7190 tcp_eat_recv_skb net/ipv4/tcp.c:1565 [inline] tcp_recvmsg_locked+0x249d/0x3660 net/ipv4/tcp.c:2862 tcp_recvmsg+0x216/0x810 net/ipv4/tcp.c:2908 inet_recvmsg+0x147/0x250 net/ipv4/af_inet.c:883 sock_recvmsg_nosec net/socket.c:1065 [inline] sock_recvmsg+0x1a8/0x270 net/socket.c:1087 sock_read_iter+0x231/0x2f0 net/socket.c:1157 new_sync_read fs/read_write.c:491 [inline] vfs_read+0x4d0/0x980 fs/read_write.c:572 ksys_read+0x145/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88807ed44980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807ed44a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807ed44a80: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88807ed44b00: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff88807ed44b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 24 20 and $0x20,%al 2: f6 44 24 21 02 testb $0x2,0x21(%rsp) 7: 74 0c je 0x15 9: 90 nop a: 0f 0b ud2 c: 48 f7 03 08 00 00 00 testq $0x8,(%rbx) 13: 74 64 je 0x79 15: bf 01 00 00 00 mov $0x1,%edi 1a: e8 cb bf 18 f6 call 0xf618bfea 1f: e8 f6 f0 4f f6 call 0xf64ff11a 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 1b ab ff ff call 0xffffab4a <-- trapping instruction 2f: 48 c7 44 24 40 00 00 movq $0x0,0x40(%rsp) 36: 00 00 38: 9c pushf 39: 8f 44 24 40 pop 0x40(%rsp) 3d: 8b .byte 0x8b 3e: 44 rex.R 3f: 24 .byte 0x24