================================================================== BUG: KASAN: use-after-free in dev_map_enqueue+0x40/0x340 kernel/bpf/devmap.c:532 Read of size 8 at addr ffff8881196a0000 by task syz.5.5799/13727 CPU: 1 PID: 13727 Comm: syz.5.5799 Not tainted 6.1.128-syzkaller-00029-g5145d157731f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0x158/0x4e0 mm/kasan/report.c:427 kasan_report+0x13c/0x170 mm/kasan/report.c:531 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351 dev_map_enqueue+0x40/0x340 kernel/bpf/devmap.c:532 __xdp_do_redirect_frame net/core/filter.c:4319 [inline] xdp_do_redirect+0x5ed/0xc60 net/core/filter.c:4367 tun_xdp_act+0xdb/0xc00 drivers/net/tun.c:1625 tun_build_skb drivers/net/tun.c:1715 [inline] tun_get_user+0xb35/0x3a90 drivers/net/tun.c:1818 tun_chr_write_iter+0x129/0x210 drivers/net/tun.c:2044 call_write_iter include/linux/fs.h:2274 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0xaf6/0xed0 fs/read_write.c:584 ksys_write+0x199/0x2c0 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4d1778bc1f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007f4d18673000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f4d179a5fa0 RCX: 00007f4d1778bc1f RDX: 000000000000007e RSI: 0000200000000300 RDI: 00000000000000c8 RBP: 00007f4d1780e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000007e R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4d179a5fa0 R15: 00007ffe3c68b0e8 Allocated by task 12590: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x9c/0xb0 mm/kasan/common.c:388 kasan_kmalloc include/linux/kasan.h:212 [inline] kmalloc_trace+0x44/0xa0 mm/slab_common.c:1033 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] bpf_raw_tp_link_attach+0x1c1/0x6b0 kernel/bpf/syscall.c:3357 bpf_raw_tracepoint_open+0x22d/0x4a0 kernel/bpf/syscall.c:3399 __sys_bpf+0x4f5/0x7f0 kernel/bpf/syscall.c:5049 __do_sys_bpf kernel/bpf/syscall.c:5111 [inline] __se_sys_bpf kernel/bpf/syscall.c:5109 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5109 x64_sys_call+0x87f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 12589: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0x131/0x180 mm/kasan/common.c:241 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249 kasan_slab_free include/linux/kasan.h:178 [inline] slab_free_hook mm/slub.c:1745 [inline] slab_free_freelist_hook mm/slub.c:1771 [inline] slab_free mm/slub.c:3686 [inline] __kmem_cache_free+0x21d/0x410 mm/slub.c:3702 kfree+0x7a/0xf0 mm/slab_common.c:990 bpf_raw_tp_link_dealloc+0x15/0x20 kernel/bpf/syscall.c:3184 bpf_link_free+0x394/0x3f0 kernel/bpf/syscall.c:2748 bpf_link_put kernel/bpf/syscall.c:2770 [inline] bpf_link_release+0x170/0x180 kernel/bpf/syscall.c:2779 __fput+0x1e5/0x870 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x24d/0x2e0 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x94/0xa0 kernel/entry/common.c:177 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x26/0x130 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb4/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 kvfree_call_rcu+0x9f/0x800 kernel/rcu/tree.c:3445 kernfs_unlink_open_file+0x327/0x3d0 fs/kernfs/file.c:635 kernfs_fop_release+0x253/0x310 fs/kernfs/file.c:807 __fput+0x1e5/0x870 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x24d/0x2e0 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x94/0xa0 kernel/entry/common.c:177 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x26/0x130 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb4/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 kvfree_call_rcu+0x9f/0x800 kernel/rcu/tree.c:3445 kernfs_unlink_open_file+0x327/0x3d0 fs/kernfs/file.c:635 kernfs_fop_release+0x253/0x310 fs/kernfs/file.c:807 __fput+0x1e5/0x870 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x24d/0x2e0 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x94/0xa0 kernel/entry/common.c:177 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x26/0x130 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff8881196a0000 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff8881196a0000, ffff8881196a0060) The buggy address belongs to the physical page: page:ffffea000465a800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1196a0 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea00044085c0 dead000000000002 ffff888100042900 raw: 0000000000000000 0000000000200020 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 102, tgid 102 (udevd), ts 5592613562, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x213/0x220 mm/page_alloc.c:2637 prep_new_page+0x1b/0x110 mm/page_alloc.c:2644 get_page_from_freelist+0x3a98/0x3b10 mm/page_alloc.c:4539 __alloc_pages+0x234/0x610 mm/page_alloc.c:5837 alloc_slab_page+0x6c/0xf0 allocate_slab mm/slub.c:1962 [inline] new_slab+0x90/0x3e0 mm/slub.c:2015 ___slab_alloc+0x6f9/0xb80 mm/slub.c:3203 __slab_alloc+0x5d/0xa0 mm/slub.c:3302 slab_alloc_node mm/slub.c:3387 [inline] __kmem_cache_alloc_node+0x207/0x2a0 mm/slub.c:3462 kmalloc_trace+0x2a/0xa0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] kernfs_get_open_node fs/kernfs/file.c:574 [inline] kernfs_fop_open+0x70e/0xb10 fs/kernfs/file.c:742 do_dentry_open+0x891/0x1250 fs/open.c:884 vfs_open+0x73/0x80 fs/open.c:1015 do_open fs/namei.c:3625 [inline] path_openat+0x2532/0x2d60 fs/namei.c:3782 do_filp_open+0x230/0x480 fs/namei.c:3809 do_sys_openat2+0x151/0x870 fs/open.c:1341 page_owner free stack trace missing Memory state around the buggy address: ffff88811969ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88811969ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881196a0000: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8881196a0080: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8881196a0100: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ================================================================== general protection fault, probably for non-canonical address 0xe0f39c2900000669: 0000 [#1] PREEMPT SMP KASAN KASAN: maybe wild-memory-access in range [0x079d014800003348-0x079d01480000334f] CPU: 1 PID: 13727 Comm: syz.5.5799 Tainted: G B 6.1.128-syzkaller-00029-g5145d157731f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:__xdp_enqueue kernel/bpf/devmap.c:481 [inline] RIP: 0010:dev_map_enqueue+0x91/0x340 kernel/bpf/devmap.c:534 Code: d0 00 00 00 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 ef 9c 25 00 bb 20 02 00 00 49 03 5d 00 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 d0 9c 25 00 48 83 3b 00 0f 84 eb RSP: 0018:ffffc9000106f7a0 EFLAGS: 00010207 RAX: 00f3a02900000669 RBX: 079d01480000334e RCX: ffffffff8197a311 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888116bcefb0 RBP: ffffc9000106f7e0 R08: ffffffff8144b2d3 R09: fffffbfff0f6e8fd R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff888116bcefb0 R14: ffff888116bceee0 R15: ffff88812cdd8000 FS: 00007f4d186736c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2869eb CR3: 0000000115c46000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __xdp_do_redirect_frame net/core/filter.c:4319 [inline] xdp_do_redirect+0x5ed/0xc60 net/core/filter.c:4367 tun_xdp_act+0xdb/0xc00 drivers/net/tun.c:1625 tun_build_skb drivers/net/tun.c:1715 [inline] tun_get_user+0xb35/0x3a90 drivers/net/tun.c:1818 tun_chr_write_iter+0x129/0x210 drivers/net/tun.c:2044 call_write_iter include/linux/fs.h:2274 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0xaf6/0xed0 fs/read_write.c:584 ksys_write+0x199/0x2c0 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4d1778bc1f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007f4d18673000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f4d179a5fa0 RCX: 00007f4d1778bc1f RDX: 000000000000007e RSI: 0000200000000300 RDI: 00000000000000c8 RBP: 00007f4d1780e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000007e R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4d179a5fa0 R15: 00007ffe3c68b0e8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__xdp_enqueue kernel/bpf/devmap.c:481 [inline] RIP: 0010:dev_map_enqueue+0x91/0x340 kernel/bpf/devmap.c:534 Code: d0 00 00 00 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 ef 9c 25 00 bb 20 02 00 00 49 03 5d 00 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 d0 9c 25 00 48 83 3b 00 0f 84 eb RSP: 0018:ffffc9000106f7a0 EFLAGS: 00010207 RAX: 00f3a02900000669 RBX: 079d01480000334e RCX: ffffffff8197a311 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888116bcefb0 RBP: ffffc9000106f7e0 R08: ffffffff8144b2d3 R09: fffffbfff0f6e8fd R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff888116bcefb0 R14: ffff888116bceee0 R15: ffff88812cdd8000 FS: 00007f4d186736c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2869eb CR3: 0000000115c46000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: d0 00 rolb (%rax) 2: 00 00 add %al,(%rax) 4: 4c 89 e8 mov %r13,%rax 7: 48 c1 e8 03 shr $0x3,%rax b: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 10: 74 08 je 0x1a 12: 4c 89 ef mov %r13,%rdi 15: e8 ef 9c 25 00 call 0x259d09 1a: bb 20 02 00 00 mov $0x220,%ebx 1f: 49 03 5d 00 add 0x0(%r13),%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 df mov %rbx,%rdi 34: e8 d0 9c 25 00 call 0x259d09 39: 48 83 3b 00 cmpq $0x0,(%rbx) 3d: 0f .byte 0xf 3e: 84 eb test %ch,%bl