================================================================== BUG: KASAN: use-after-free in dev_map_generic_redirect+0x9f/0x7d0 kernel/bpf/devmap.c:665 Read of size 8 at addr ffff88812ee0ff80 by task syz.2.371/1278 CPU: 0 PID: 1278 Comm: syz.2.371 Not tainted 6.1.112-syzkaller-00014-g7160754546da #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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:665 xdp_do_generic_redirect_map net/core/filter.c:4390 [inline] xdp_do_generic_redirect+0x42e/0xb40 net/core/filter.c:4449 do_xdp_generic+0x53e/0x800 net/core/dev.c:4958 __netif_receive_skb_core+0x19ae/0x43d0 net/core/dev.c:5365 __netif_receive_skb_one_core net/core/dev.c:5542 [inline] __netif_receive_skb+0x11c/0x530 net/core/dev.c:5658 netif_receive_skb_internal net/core/dev.c:5744 [inline] netif_receive_skb+0xb0/0x480 net/core/dev.c:5803 tun_rx_batched+0x1c0/0x8f0 drivers/net/tun.c:1548 tun_get_user+0x287e/0x3a90 drivers/net/tun.c:1998 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: 0033:0x7fb5ded7d1ff Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 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 1c 8e 02 00 48 RSP: 002b:00007fb5dfb07000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fb5def35f80 RCX: 00007fb5ded7d1ff RDX: 000000000000006a RSI: 0000000020000180 RDI: 00000000000000c8 RBP: 00007fb5dedf175e R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000006a R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb5def35f80 R15: 00007fff23fd8c58 Allocated by task 434: 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:557 [inline] kzalloc include/linux/slab.h:693 [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:3627 [inline] path_openat+0x2532/0x2d60 fs/namei.c:3784 do_filp_open+0x230/0x480 fs/namei.c:3811 do_sys_openat2+0x151/0x870 fs/open.c:1341 do_sys_open fs/open.c:1357 [inline] __do_sys_openat fs/open.c:1373 [inline] __se_sys_openat fs/open.c:1368 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1368 x64_sys_call+0x6bf/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258 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 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 ffff88812ee0ff80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff88812ee0ff80, ffff88812ee0ffe0) The buggy address belongs to the physical page: page:ffffea0004bb83c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88812ee0fb00 pfn:0x12ee0f flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffff888100040310 ffffea0004bb8648 ffff888100042900 raw: ffff88812ee0fb00 0000000000200011 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 102, tgid 102 (udevd), ts 25022513835, free_ts 25021201364 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+0x1af/0x250 mm/slub.c:3460 kmalloc_trace+0x2a/0xa0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:557 [inline] kzalloc include/linux/slab.h:693 [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:3627 [inline] path_openat+0x2532/0x2d60 fs/namei.c:3784 do_filp_open+0x230/0x480 fs/namei.c:3811 do_sys_openat2+0x151/0x870 fs/open.c:1341 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_pages+0x7c/0x90 mm/page_alloc.c:5828 _pgd_free arch/x86/mm/pgtable.c:420 [inline] pgd_free+0x17d/0x190 arch/x86/mm/pgtable.c:476 mm_free_pgd kernel/fork.c:833 [inline] __mmdrop+0xb0/0x3e0 kernel/fork.c:884 mmdrop include/linux/sched/mm.h:50 [inline] __mmput+0x304/0x310 kernel/fork.c:1309 mmput+0x56/0x170 kernel/fork.c:1321 exit_mm kernel/exit.c:568 [inline] do_exit+0xb29/0x2b80 kernel/exit.c:864 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 Memory state around the buggy address: ffff88812ee0fe80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88812ee0ff00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff88812ee0ff80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88812ee10000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88812ee10080: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc ==================================================================