================================================================== BUG: KASAN: slab-use-after-free in bpf_link_free+0x234/0x2d0 kernel/bpf/syscall.c:3078 Read of size 8 at addr ffff88802bdb4f10 by task syz-executor.3/6647 CPU: 1 PID: 6647 Comm: syz-executor.3 Not tainted 6.9.0-rc7-syzkaller-01813-gb9d5f5711dd8 #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: 0033:0x7f30ef47cc5a 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:00007ffc56d320b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007f30ef47cc5a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000b RBP: 00007ffc56d32188 R08: 00007f30ef400000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000293 R12: 000000000001e650 R13: 00007f30ef5abf8c R14: 00007f30ef5abf80 R15: 0000000000000032 Allocated by task 6648: 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:5719 __do_sys_bpf kernel/bpf/syscall.c:5784 [inline] __se_sys_bpf kernel/bpf/syscall.c:5782 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5782 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 23: 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 __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 ffff88802bdb4f00 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 16 bytes inside of freed 128-byte region [ffff88802bdb4f00, ffff88802bdb4f80) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2bdb4 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff8880150418c0 dead000000000122 0000000000000000 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5083, tgid -1425155955 (syz-fuzzer), ts 5099, free_ts 122945403949 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] __do_kmalloc_node mm/slub.c:3971 [inline] __kmalloc+0x2e5/0x4a0 mm/slub.c:3985 kmalloc include/linux/slab.h:632 [inline] kzalloc include/linux/slab.h:749 [inline] task_numa_fault+0x3837/0x46d0 kernel/sched/fair.c:3107 do_numa_page mm/memory.c:5153 [inline] handle_pte_fault mm/memory.c:5306 [inline] __handle_mm_fault+0x36c6/0x7250 mm/memory.c:5441 handle_mm_fault+0x3c2/0x8a0 mm/memory.c:5606 do_user_addr_fault arch/x86/mm/fault.c:1382 [inline] handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x2a8/0x8a0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 page last free pid 955 tgid 955 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 bpf_ringbuf_free kernel/bpf/ringbuf.c:223 [inline] ringbuf_map_free+0xc2/0x120 kernel/bpf/ringbuf.c:232 bpf_map_free_deferred+0xe6/0x110 kernel/bpf/syscall.c:746 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 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff88802bdb4e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802bdb4e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802bdb4f00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802bdb4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802bdb5000: fa fb fb fb fb fb fb fb fb fb fc fc fc fc fa fb ==================================================================