================================================================== BUG: KASAN: slab-use-after-free in __bpf_trace_run kernel/trace/bpf_trace.c:2376 [inline] BUG: KASAN: slab-use-after-free in bpf_trace_run1+0xcb/0x510 kernel/trace/bpf_trace.c:2430 Read of size 8 at addr ffff888037bb2d18 by task syz-executor.4/17239 CPU: 1 PID: 17239 Comm: syz-executor.4 Not tainted 6.8.0-syzkaller-05234-gcc9b22dfa735 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 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_trace_run kernel/trace/bpf_trace.c:2376 [inline] bpf_trace_run1+0xcb/0x510 kernel/trace/bpf_trace.c:2430 __traceiter_rcu_utilization+0x74/0xb0 include/trace/events/rcu.h:27 trace_rcu_utilization+0x194/0x1c0 include/trace/events/rcu.h:27 rcu_note_context_switch+0xc7c/0xff0 kernel/rcu/tree_plugin.h:360 __schedule+0x345/0x4a20 kernel/sched/core.c:6635 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7058 irqentry_exit+0x5e/0x90 kernel/entry/common.c:348 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:jbd_lock_bh_journal_head+0x0/0x120 include/linux/jbd2.h:342 Code: 46 f2 25 ff 90 0f 0b e8 3e f2 25 ff 90 0f 0b e8 36 f2 25 ff 90 0f 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <55> 41 57 41 56 41 54 53 49 89 fc e8 10 f2 25 ff bf 01 00 00 00 e8 RSP: 0018:ffffc900041bf7c8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff944bf403 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff888038226658 RBP: dffffc0000000000 R08: ffff888039ec3f37 R09: 0000000000000000 R10: ffff888039ec3f28 R11: ffffed10073d87e7 R12: 1ffff11007044ccb R13: ffff888038226658 R14: ffff8880382266b8 R15: ffff888039ec3f00 jbd2_journal_add_journal_head+0x108/0x480 fs/jbd2/journal.c:2922 jbd2_journal_get_create_access+0x49/0x460 fs/jbd2/transaction.c:1289 __ext4_journal_get_create_access+0xb3/0x560 fs/ext4/ext4_jbd2.c:328 ext4_getblk+0x514/0x850 fs/ext4/inode.c:860 ext4_bread+0x2e/0x180 fs/ext4/inode.c:889 ext4_append+0x327/0x5c0 fs/ext4/namei.c:83 ext4_init_new_dir+0x33e/0xa30 fs/ext4/namei.c:2977 ext4_mkdir+0x4f7/0xcf0 fs/ext4/namei.c:3023 vfs_mkdir+0x2f9/0x4b0 fs/namei.c:4124 do_mkdirat+0x264/0x3a0 fs/namei.c:4147 __do_sys_mkdirat fs/namei.c:4162 [inline] __se_sys_mkdirat fs/namei.c:4160 [inline] __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4160 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f3a3c27c8a7 Code: 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 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:00007ffc8988d608 EFLAGS: 00000202 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007ffc8988d690 RCX: 00007f3a3c27c8a7 RDX: 00000000000001ff RSI: 00007ffc8988d690 RDI: 00000000ffffff9c RBP: 00007ffc8988d66c R08: 0000000000000004 R09: 00007ffc8988d3a6 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000032 R13: 000000000006ee70 R14: 000000000006eda1 R15: 0000000000000003 Allocated by task 18821: 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+0x1d9/0x360 mm/slub.c:4012 kmalloc include/linux/slab.h:590 [inline] kzalloc include/linux/slab.h:711 [inline] bpf_raw_tp_link_attach+0x2a0/0x6e0 kernel/bpf/syscall.c:3816 bpf_raw_tracepoint_open+0x1c2/0x240 kernel/bpf/syscall.c:3863 __sys_bpf+0x3c0/0x810 kernel/bpf/syscall.c:5673 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Freed by task 18822: 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:589 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:4299 [inline] kfree+0x14a/0x380 mm/slub.c:4409 bpf_link_release+0x3b/0x50 kernel/bpf/syscall.c:3071 __fput+0x429/0x8a0 fs/file_table.c:423 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+0x176e/0x1850 kernel/signal.c:2907 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 The buggy address belongs to the object at ffff888037bb2d00 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 24 bytes inside of freed 128-byte region [ffff888037bb2d00, ffff888037bb2d80) The buggy address belongs to the physical page: page:ffffea0000deec80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x37bb2 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888014c418c0 ffffea0000cd1dc0 dead000000000002 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5090, tgid 5090 (syz-executor.3), ts 76427141203, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311 __alloc_pages+0x256/0x680 mm/page_alloc.c:4569 __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:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd1b/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] __do_kmalloc_node mm/slub.c:3980 [inline] __kmalloc+0x2e3/0x4a0 mm/slub.c:3994 kmalloc include/linux/slab.h:594 [inline] kzalloc include/linux/slab.h:711 [inline] udp_tunnel_nic_alloc net/ipv4/udp_tunnel_nic.c:728 [inline] udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:804 [inline] udp_tunnel_nic_netdevice_event+0x5b6/0x12f0 net/ipv4/udp_tunnel_nic.c:893 notifier_call_chain+0x18f/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline] call_netdevice_notifiers net/core/dev.c:2002 [inline] register_netdevice+0x15b2/0x1a20 net/core/dev.c:10307 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:376 [inline] nsim_create+0x39c/0x480 drivers/net/netdevsim/netdev.c:434 __nsim_dev_port_add+0x6c0/0xae0 drivers/net/netdevsim/dev.c:1390 nsim_dev_port_add_all+0x33/0xf0 drivers/net/netdevsim/dev.c:1446 nsim_drv_probe+0x85f/0xb80 drivers/net/netdevsim/dev.c:1604 really_probe+0x29e/0xc50 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x3e0 drivers/base/dd.c:800 page_owner free stack trace missing Memory state around the buggy address: ffff888037bb2c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc ffff888037bb2c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888037bb2d00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888037bb2d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888037bb2e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 46 rex.RX 1: f2 25 ff 90 0f 0b repnz and $0xb0f90ff,%eax 7: e8 3e f2 25 ff call 0xff25f24a c: 90 nop d: 0f 0b ud2 f: e8 36 f2 25 ff call 0xff25f24a 14: 90 nop 15: 0f 0b ud2 17: 0f 1f 00 nopl (%rax) 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: 55 push %rbp <-- trapping instruction 2b: 41 57 push %r15 2d: 41 56 push %r14 2f: 41 54 push %r12 31: 53 push %rbx 32: 49 89 fc mov %rdi,%r12 35: e8 10 f2 25 ff call 0xff25f24a 3a: bf 01 00 00 00 mov $0x1,%edi 3f: e8 .byte 0xe8