================================================================== BUG: KASAN: use-after-free in dev_map_generic_redirect+0x9f/0x7d0 kernel/bpf/devmap.c:668 Read of size 8 at addr ffff88812a5c7380 by task syz.0.11452/26908 CPU: 1 PID: 26908 Comm: syz.0.11452 Not tainted 6.1.115-syzkaller-00017-g22b7ded8b55b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 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_generic_redirect+0x9f/0x7d0 kernel/bpf/devmap.c:668 xdp_do_generic_redirect_map net/core/filter.c:4392 [inline] xdp_do_generic_redirect+0x42e/0xb40 net/core/filter.c:4451 do_xdp_generic+0x53e/0x800 net/core/dev.c:4966 tun_get_user+0x238a/0x3a90 drivers/net/tun.c:1920 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: 0033:0x7f9c6d1847cf 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:00007f9c6e034000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f9c6d375fa0 RCX: 00007f9c6d1847cf RDX: 0000000000000d41 RSI: 0000000020002a00 RDI: 00000000000000c8 RBP: 00007f9c6d201a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000d41 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9c6d375fa0 R15: 00007fff848a9258 Allocated by task 25028: 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] __do_kmalloc_node mm/slab_common.c:938 [inline] __kmalloc_node+0xb4/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:583 [inline] kvmalloc_node+0x221/0x640 mm/util.c:592 kvmalloc include/linux/slab.h:710 [inline] alloc_fdtable+0x163/0x2a0 fs/file.c:137 dup_fd+0x6a6/0x950 fs/file.c:336 copy_files+0x76/0xe0 kernel/fork.c:1736 copy_process+0x11e9/0x3530 kernel/fork.c:2355 kernel_clone+0x229/0x890 kernel/fork.c:2783 __do_sys_clone kernel/fork.c:2926 [inline] __se_sys_clone kernel/fork.c:2910 [inline] __x64_sys_clone+0x231/0x280 kernel/fork.c:2910 x64_sys_call+0x1b0/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:57 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 26456: 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 kvfree+0x35/0x40 mm/util.c:639 __free_fdtable fs/file.c:37 [inline] put_files_struct+0x2a8/0x320 fs/file.c:432 exit_files+0x80/0xa0 fs/file.c:445 do_exit+0xb9e/0x2b80 kernel/exit.c:872 do_group_exit+0x21a/0x2d0 kernel/exit.c:1027 get_signal+0x169d/0x1820 kernel/signal.c:2888 arch_do_signal_or_restart+0xb0/0x16f0 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x74/0xa0 kernel/entry/common.c:174 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 trie_update_elem+0x7f6/0xc10 kernel/bpf/lpm_trie.c:433 bpf_map_update_value+0x23a/0x410 kernel/bpf/syscall.c:228 generic_map_update_batch+0x595/0x8c0 kernel/bpf/syscall.c:1679 bpf_map_do_batch+0x4cc/0x630 __sys_bpf+0x66b/0x7f0 __do_sys_bpf kernel/bpf/syscall.c:5106 [inline] __se_sys_bpf kernel/bpf/syscall.c:5104 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5104 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 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 ffff88812a5c7380 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff88812a5c7380, ffff88812a5c73e0) The buggy address belongs to the physical page: page:ffffea0004a971c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12a5c7 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea00044db400 dead000000000004 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 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 355, tgid 355 (kworker/1:3), ts 342521944760, free_ts 342519038446 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x213/0x220 mm/page_alloc.c:2590 prep_new_page+0x1b/0x110 mm/page_alloc.c:2597 get_page_from_freelist+0x2980/0x2a10 mm/page_alloc.c:4439 __alloc_pages+0x234/0x610 mm/page_alloc.c:5728 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:557 [inline] dst_cow_metrics_generic+0x55/0x1c0 net/core/dst.c:199 dst_metrics_write_ptr include/net/dst.h:119 [inline] dst_metric_set include/net/dst.h:180 [inline] icmp6_dst_alloc+0x363/0x510 net/ipv6/route.c:3282 ndisc_send_skb+0x28b/0xdc0 net/ipv6/ndisc.c:491 ndisc_send_ns+0xc8/0x150 net/ipv6/ndisc.c:669 addrconf_dad_work+0xb1b/0x16b0 net/ipv6/addrconf.c:4225 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2299 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1498 [inline] free_pcp_prepare mm/page_alloc.c:1572 [inline] free_unref_page_prepare+0x83d/0x850 mm/page_alloc.c:3511 free_unref_page+0xb2/0x5c0 mm/page_alloc.c:3607 free_the_page mm/page_alloc.c:798 [inline] __free_pages+0x61/0xf0 mm/page_alloc.c:5817 __free_slab+0xce/0x1a0 mm/slub.c:2039 free_slab mm/slub.c:2054 [inline] discard_slab mm/slub.c:2060 [inline] __unfreeze_partials+0x165/0x1a0 mm/slub.c:2609 put_cpu_partial+0xa9/0x100 mm/slub.c:2685 __slab_free+0x1c8/0x280 mm/slub.c:3563 do_slab_free mm/slub.c:3640 [inline] ___cache_free+0xc6/0xd0 mm/slub.c:3696 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0xc5/0x140 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x15a/0x180 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:310 kasan_slab_alloc include/linux/kasan.h:202 [inline] slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:768 slab_alloc_node mm/slub.c:3421 [inline] kmem_cache_alloc_node+0x188/0x330 mm/slub.c:3468 __alloc_skb+0xcc/0x2d0 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1290 [inline] alloc_skb_with_frags+0xa6/0x680 net/core/skbuff.c:6162 sock_alloc_send_pskb+0x915/0xa50 net/core/sock.c:2753 Memory state around the buggy address: ffff88812a5c7280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88812a5c7300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff88812a5c7380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88812a5c7400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88812a5c7480: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================