================================================================== BUG: KASAN: slab-use-after-free in bpf_link_free+0x234/0x2d0 kernel/bpf/syscall.c:3078 Read of size 8 at addr ffff88802b715510 by task syz-executor.1/8139 CPU: 1 PID: 8139 Comm: syz-executor.1 Not tainted 6.9.0-syzkaller-08544-g4b377b4868ef #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+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f448aa7bdda Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24 RSP: 002b:00007fff580e8b20 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 000000000000000e RCX: 00007f448aa7bdda RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000d RBP: 00007f448abad980 R08: 0000001b2d620000 R09: 0000000000000316 R10: 00000000819d7a38 R11: 0000000000000293 R12: 000000000005d750 R13: 00007f448abac12c R14: 00007f448abac120 R15: 0000000000000032 Allocated by task 8141: 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+0x1db/0x370 mm/slub.c:4070 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [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+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 24: 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+0xa6/0xe0 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:2121 [inline] slab_free mm/slub.c:4353 [inline] kfree+0x153/0x3b0 mm/slub.c:4463 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2809 handle_softirqs+0x2d6/0x990 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:928 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802b715500 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 16 bytes inside of freed 128-byte region [ffff88802b715500, ffff88802b715580) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b715 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888015041a00 ffffea0000908900 dead000000000004 raw: 0000000000000000 0000000000100010 00000001ffffffff 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 0x152cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5215, tgid 5210 (syz-executor.2), ts 66425657240, free_ts 66339922481 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2353 [inline] new_slab+0x84/0x2f0 mm/slub.c:2406 ___slab_alloc+0xb07/0x12e0 mm/slub.c:3592 __slab_alloc mm/slub.c:3682 [inline] __slab_alloc_node mm/slub.c:3735 [inline] slab_alloc_node mm/slub.c:3908 [inline] __do_kmalloc_node mm/slub.c:4038 [inline] __kmalloc+0x2e5/0x4a0 mm/slub.c:4052 kmalloc include/linux/slab.h:632 [inline] kzalloc include/linux/slab.h:749 [inline] tnode_alloc net/ipv4/fib_trie.c:333 [inline] tnode_new+0xcd/0x340 net/ipv4/fib_trie.c:386 inflate net/ipv4/fib_trie.c:597 [inline] resize+0x820/0x2740 net/ipv4/fib_trie.c:870 trie_rebalance net/ipv4/fib_trie.c:1107 [inline] fib_insert_node net/ipv4/fib_trie.c:1151 [inline] fib_insert_alias+0xd2b/0x1290 net/ipv4/fib_trie.c:1165 fib_trie_unmerge+0x417/0xee0 net/ipv4/fib_trie.c:1938 fib_unmerge+0xc5/0x370 net/ipv4/fib_frontend.c:161 fib4_rule_configure+0x1a3/0xba0 net/ipv4/fib_rules.c:242 fib_nl_newrule+0x116b/0x1c50 net/core/fib_rules.c:812 rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6595 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 page last free pid 5203 tgid 5200 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347 free_unref_folios+0x1f2/0xc10 mm/page_alloc.c:2536 folios_put_refs+0x93a/0xa60 mm/swap.c:1034 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:329 __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+0x4bb/0xd60 mm/mmap.c:3282 __mmput+0x115/0x3c0 kernel/fork.c:1346 exit_mm+0x220/0x310 kernel/exit.c:568 do_exit+0x99e/0x27e0 kernel/exit.c:864 do_group_exit+0x207/0x2c0 kernel/exit.c:1026 get_signal+0x16a1/0x1740 kernel/signal.c:2911 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+0x102/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802b715400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802b715480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802b715500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802b715580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802b715600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================