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BUG: KASAN: use-after-free in dev_map_generic_redirect+0xa0/0x650 kernel/bpf/devmap.c:668
Read of size 8 at addr ffff888068350380 by task syz.9.2683/13886

CPU: 0 PID: 13886 Comm: syz.9.2683 Not tainted 6.1.116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 dev_map_generic_redirect+0xa0/0x650 kernel/bpf/devmap.c:668
 xdp_do_generic_redirect_map net/core/filter.c:4392 [inline]
 xdp_do_generic_redirect+0x4bf/0x850 net/core/filter.c:4451
 do_xdp_generic+0x50b/0x6d0 net/core/dev.c:4955
 __netif_receive_skb_core+0x1c88/0x41d0 net/core/dev.c:5357
 __netif_receive_skb_one_core net/core/dev.c:5534 [inline]
 __netif_receive_skb+0x11c/0x530 net/core/dev.c:5650
 netif_receive_skb_internal net/core/dev.c:5736 [inline]
 netif_receive_skb+0x1f4/0x890 net/core/dev.c:5795
 tun_rx_batched+0x1b3/0x8e0 drivers/net/tun.c:1548
 tun_get_user+0x2c03/0x42d0 drivers/net/tun.c:1998
 tun_chr_write_iter+0x10c/0x1f0 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+0x857/0xbc0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 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: 0033:0x7fe76217d1ff
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:00007fe763000000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe762335f80 RCX: 00007fe76217d1ff
RDX: 000000000000006a RSI: 0000000020000180 RDI: 00000000000000c8
RBP: 00007fe7621f175e R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000006a R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe762335f80 R15: 00007fff01cf4618
 </TASK>

Allocated by task 13800:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:557 [inline]
 kzalloc include/linux/slab.h:693 [inline]
 get_undo_list ipc/sem.c:1856 [inline]
 copy_semundo+0xb1/0x230 ipc/sem.c:2314
 copy_process+0x1848/0x4060 kernel/fork.c:2249
 kernel_clone+0x222/0x920 kernel/fork.c:2679
 __do_sys_clone3 kernel/fork.c:2978 [inline]
 __se_sys_clone3+0x373/0x410 kernel/fork.c:2962
 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 13801:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 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+0x25c/0x3c0 mm/slub.c:3674
 exit_sem+0x197a/0x19e0 ipc/sem.c:2447
 do_exit+0xa44/0x26a0 kernel/exit.c:864
 do_group_exit+0x202/0x2b0 kernel/exit.c:1021
 get_signal+0x16f7/0x17d0 kernel/signal.c:2870
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 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 ffff888068350380
 which belongs to the cache kmalloc-cg-96 of size 96
The buggy address is located 0 bytes inside of
 96-byte region [ffff888068350380, ffff8880683503e0)

The buggy address belongs to the physical page:
page:ffffea0001a0d400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x68350
memcg:ffff888028720801
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea0001d769c0 dead000000000006 ffff888017c428c0
raw: 0000000000000000 0000000000200020 00000001ffffffff ffff888028720801
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 9676, tgid 9676 (syz.8.1546), ts 286345016789, free_ts 286194811470
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4313
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5589
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437
 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026
 kmalloc include/linux/slab.h:557 [inline]
 kzalloc include/linux/slab.h:693 [inline]
 get_undo_list ipc/sem.c:1856 [inline]
 copy_semundo+0xb1/0x230 ipc/sem.c:2314
 copy_process+0x1848/0x4060 kernel/fork.c:2249
 kernel_clone+0x222/0x920 kernel/fork.c:2679
 __do_sys_clone3 kernel/fork.c:2978 [inline]
 __se_sys_clone3+0x373/0x410 kernel/fork.c:2962
 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
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3510
 release_pages+0x2836/0x2b40 mm/swap.c:1055
 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:254 [inline]
 tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261
 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361
 exit_mmap+0x3c3/0x9f0 mm/mmap.c:3239
 __mmput+0x115/0x3c0 kernel/fork.c:1199
 exit_mm+0x226/0x300 kernel/exit.c:565
 do_exit+0x9f6/0x26a0 kernel/exit.c:858
 do_group_exit+0x202/0x2b0 kernel/exit.c:1021
 get_signal+0x16f7/0x17d0 kernel/signal.c:2870
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87

Memory state around the buggy address:
 ffff888068350280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888068350300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff888068350380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                   ^
 ffff888068350400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888068350480: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
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