================================================================== BUG: KASAN: use-after-free in dev_map_generic_redirect+0xa8/0x59c kernel/bpf/devmap.c:665 Read of size 8 at addr ffff0000f0c64900 by task syz.3.470/5836 CPU: 1 PID: 5836 Comm: syz.3.470 Not tainted 6.1.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x174/0x4c0 mm/kasan/report.c:395 kasan_report+0xd4/0x130 mm/kasan/report.c:495 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351 dev_map_generic_redirect+0xa8/0x59c kernel/bpf/devmap.c:665 xdp_do_generic_redirect_map net/core/filter.c:4390 [inline] xdp_do_generic_redirect+0x3e8/0x6e0 net/core/filter.c:4449 do_xdp_generic+0x460/0x634 net/core/dev.c:4947 tun_get_user+0x1e40/0x386c drivers/net/tun.c:1920 tun_chr_write_iter+0xfc/0x204 drivers/net/tun.c:2044 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x610/0x91c fs/read_write.c:584 ksys_write+0x15c/0x26c fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Allocated by task 4301: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:955 [inline] __kmalloc+0xd8/0x1c4 mm/slab_common.c:968 kmalloc include/linux/slab.h:561 [inline] inotify_handle_inode_event+0x2c0/0x8ec fs/notify/inotify/inotify_fsnotify.c:96 fsnotify_handle_inode_event fs/notify/fsnotify.c:264 [inline] fsnotify_handle_event fs/notify/fsnotify.c:316 [inline] send_to_group fs/notify/fsnotify.c:364 [inline] fsnotify+0x1818/0x1cd4 fs/notify/fsnotify.c:570 __fsnotify_parent+0x414/0x630 fs/notify/fsnotify.c:230 fsnotify_parent include/linux/fsnotify.h:77 [inline] fsnotify_file include/linux/fsnotify.h:105 [inline] fsnotify_close include/linux/fsnotify.h:347 [inline] __fput+0x588/0x7c8 fs/file_table.c:306 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x240/0x2f0 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x2148/0x3474 arch/arm64/kernel/signal.c:1132 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x168 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Freed by task 3911: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516 ____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x2c0/0x4b4 mm/slub.c:3674 kfree+0xcc/0x1b8 mm/slab_common.c:1007 inotify_free_event+0x20/0x30 fs/notify/inotify/inotify_fsnotify.c:190 fsnotify_destroy_event+0x100/0x124 fs/notify/notification.c:67 inotify_read+0x470/0xa68 fs/notify/inotify/inotify_user.c:275 vfs_read+0x280/0x8b4 fs/read_write.c:468 ksys_read+0x15c/0x26c fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __arm64_sys_read+0x7c/0x90 fs/read_write.c:621 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Last potentially related work creation: kasan_save_stack+0x40/0x70 mm/kasan/common.c:45 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496 call_rcu+0xfc/0xa40 kernel/rcu/tree.c:2844 nf_hook_entries_free net/netfilter/core.c:88 [inline] __nf_register_net_hook+0x804/0xa58 net/netfilter/core.c:445 nf_register_net_hook+0xc4/0x1a4 net/netfilter/core.c:566 nf_register_net_hooks+0x58/0x1b4 net/netfilter/core.c:582 ip6t_register_table+0x3bc/0x5cc net/ipv6/netfilter/ip6_tables.c:1789 ip6table_mangle_table_init+0x4c/0x78 net/ipv6/netfilter/ip6table_mangle.c:84 xt_find_table_lock+0x22c/0x38c net/netfilter/x_tables.c:1259 xt_request_find_table_lock+0x38/0x118 net/netfilter/x_tables.c:1284 get_info net/ipv6/netfilter/ip6_tables.c:981 [inline] do_ip6t_get_ctl+0x7b4/0x1700 net/ipv6/netfilter/ip6_tables.c:1670 nf_getsockopt+0x264/0x284 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x2dc/0x444 net/ipv6/ipv6_sockglue.c:1513 tcp_getsockopt+0xcc/0xe8 net/ipv4/tcp.c:4450 sock_common_getsockopt+0xa8/0xc4 net/core/sock.c:3652 __sys_getsockopt+0x1e8/0x484 net/socket.c:2327 __do_sys_getsockopt net/socket.c:2342 [inline] __se_sys_getsockopt net/socket.c:2339 [inline] __arm64_sys_getsockopt+0xb8/0xd4 net/socket.c:2339 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 The buggy address belongs to the object at ffff0000f0c64900 which belongs to the cache kmalloc-cg-128 of size 128 The buggy address is located 0 bytes inside of 128-byte region [ffff0000f0c64900, ffff0000f0c64980) The buggy address belongs to the physical page: page:0000000068ad1603 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x130c64 memcg:ffff0000f0c63a01 flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 dead000000000100 dead000000000122 ffff0000c0002d80 raw: 0000000000000000 0000000000100010 00000001ffffffff ffff0000f0c63a01 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f0c64800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f0c64880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff0000f0c64900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000f0c64980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000f0c64a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc ==================================================================