================================================================== BUG: KASAN: slab-use-after-free in bpf_link_free+0x234/0x2d0 kernel/bpf/syscall.c:3078 Read of size 8 at addr ffff888011469b10 by task syz-executor.1/6398 CPU: 0 PID: 6398 Comm: syz-executor.1 Not tainted 6.9.0-syzkaller-12400-g6fbf71854e2d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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 bpf_link_free+0x234/0x2d0 kernel/bpf/syscall.c:3078 bpf_link_put_direct kernel/bpf/syscall.c:3106 [inline] bpf_link_release+0x7b/0x90 kernel/bpf/syscall.c:3113 __fput+0x408/0x8b0 fs/file_table.c:422 task_work_run+0x251/0x310 kernel/task_work.c:180 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 RIP: 0033:0x7fe75847cee9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe75916f0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fe7585ac120 RCX: 00007fe75847cee9 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000004 RBP: 00007fe7584c949e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fe7585ac120 R15: 00007ffe4ae3abc8 Allocated by task 6385: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace_noprof+0x19c/0x2c0 mm/slub.c:4152 kmalloc_noprof include/linux/slab.h:660 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] bpf_raw_tp_link_attach+0x2a0/0x6e0 kernel/bpf/syscall.c:3858 bpf_raw_tracepoint_open+0x1c2/0x240 kernel/bpf/syscall.c:3905 __sys_bpf+0x3c0/0x810 kernel/bpf/syscall.c:5729 __do_sys_bpf kernel/bpf/syscall.c:5794 [inline] __se_sys_bpf kernel/bpf/syscall.c:5792 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5792 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 6399: 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:2195 [inline] slab_free mm/slub.c:4436 [inline] kfree+0x149/0x360 mm/slub.c:4557 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0xaff/0x1830 kernel/rcu/tree.c:2809 handle_softirqs+0x2c6/0x970 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:3072 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3176 bpf_link_free+0x1f8/0x2d0 kernel/bpf/syscall.c:3076 bpf_link_put_direct kernel/bpf/syscall.c:3106 [inline] bpf_link_release+0x7b/0x90 kernel/bpf/syscall.c:3113 __fput+0x408/0x8b0 fs/file_table.c:422 task_work_run+0x251/0x310 kernel/task_work.c:180 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 ffff888011469b00 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 16 bytes inside of freed 128-byte region [ffff888011469b00, ffff888011469b80) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11469 anon flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000000 ffff888015041a00 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080100010 00000001ffffefff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 2897, tgid 2897 (kworker/u8:8), ts 84640710621, free_ts 84523372123 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x2e2d/0x2ee0 mm/page_alloc.c:3402 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4660 __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:2264 allocate_slab+0x5a/0x2e0 mm/slub.c:2427 new_slab mm/slub.c:2480 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3666 __slab_alloc+0x58/0xa0 mm/slub.c:3756 __slab_alloc_node mm/slub.c:3809 [inline] slab_alloc_node mm/slub.c:3988 [inline] kmalloc_trace_noprof+0x1d5/0x2c0 mm/slub.c:4147 kmalloc_noprof include/linux/slab.h:660 [inline] __hw_addr_create net/core/dev_addr_lists.c:60 [inline] __hw_addr_add_ex+0x1a8/0x610 net/core/dev_addr_lists.c:118 __dev_mc_add net/core/dev_addr_lists.c:867 [inline] dev_mc_add+0xa3/0x110 net/core/dev_addr_lists.c:885 igmp6_group_added+0x1a4/0x710 net/ipv6/mcast.c:680 __ipv6_dev_mc_inc+0x8b8/0xa90 net/ipv6/mcast.c:949 addrconf_join_solict net/ipv6/addrconf.c:2240 [inline] addrconf_dad_begin net/ipv6/addrconf.c:4101 [inline] addrconf_dad_work+0x448/0x16f0 net/ipv6/addrconf.c:4226 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f2/0x390 kernel/kthread.c:389 page last free pid 5243 tgid 5242 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1088 [inline] free_unref_folios+0xf23/0x19e0 mm/page_alloc.c:2614 folios_put_refs+0x93a/0xa60 mm/swap.c:1024 free_pages_and_swap_cache+0x5c8/0x690 mm/swap_state.c:332 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465 exit_mmap+0x44f/0xc80 mm/mmap.c:3354 __mmput+0x115/0x3c0 kernel/fork.c:1346 exit_mm+0x220/0x310 kernel/exit.c:565 do_exit+0x9aa/0x27e0 kernel/exit.c:861 do_group_exit+0x207/0x2c0 kernel/exit.c:1023 get_signal+0x16a1/0x1740 kernel/signal.c:2909 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888011469a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc ffff888011469a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888011469b00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888011469b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888011469c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================