================================================================== BUG: KASAN: slab-use-after-free in bpf_link_free+0x234/0x2d0 kernel/bpf/syscall.c:3078 Read of size 8 at addr ffff88802d8c6210 by task syz-executor.2/8184 CPU: 0 PID: 8184 Comm: syz-executor.2 Not tainted 6.9.0-rc7-syzkaller-02060-g5c1672705a1a #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 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 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] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0033:0x7f0e880301a6 Code: Unable to access opcode bytes at 0x7f0e8803017c. RSP: 002b:00007f0e88e100f0 EFLAGS: 00000246 RAX: 0000000000000042 RBX: 00007f0e881abf80 RCX: 00007f0e880c949e RDX: 0000000000000000 RSI: 0000000020000600 RDI: 0000000000000011 RBP: 00007f0e880c949e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f0e881abf80 R15: 00007fff1cf95158 Allocated by task 8184: 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:4003 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:5724 __do_sys_bpf kernel/bpf/syscall.c:5789 [inline] __se_sys_bpf kernel/bpf/syscall.c:5787 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5787 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 15: 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:2111 [inline] slab_free mm/slub.c:4286 [inline] kfree+0x153/0x3b0 mm/slub.c:4396 rcu_do_batch kernel/rcu/tree.c:2196 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2471 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:388 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:2734 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:2838 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 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 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] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 The buggy address belongs to the object at ffff88802d8c6200 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 16 bytes inside of freed 128-byte region [ffff88802d8c6200, ffff88802d8c6280) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2d8c6 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff8880150418c0 dead000000000100 dead000000000122 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 0x12820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY), pid 138, tgid 784088163 (kworker/u8:5), ts 138, free_ts 73586070297 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:2180 allocate_slab mm/slub.c:2343 [inline] new_slab+0x84/0x2f0 mm/slub.c:2396 ___slab_alloc+0xc73/0x1260 mm/slub.c:3530 __slab_alloc mm/slub.c:3615 [inline] __slab_alloc_node mm/slub.c:3668 [inline] slab_alloc_node mm/slub.c:3841 [inline] kmalloc_trace+0x269/0x370 mm/slub.c:3998 kmalloc include/linux/slab.h:628 [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:3267 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 page last free pid 5107 tgid 5107 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_page+0x37/0x3f0 mm/page_alloc.c:2487 __slab_free+0x31b/0x3d0 mm/slub.c:4198 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x5e/0xc0 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:3804 [inline] slab_alloc_node mm/slub.c:3851 [inline] kmalloc_trace+0x16f/0x370 mm/slub.c:3998 kmalloc include/linux/slab.h:628 [inline] rtnl_newlink+0xf2/0x20a0 net/core/rtnetlink.c:3739 rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6595 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8e1/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2199 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 Memory state around the buggy address: ffff88802d8c6100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc ffff88802d8c6180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802d8c6200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802d8c6280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802d8c6300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================