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BUG: KASAN: slab-use-after-free in skb_headlen include/linux/skbuff.h:2405 [inline]
BUG: KASAN: slab-use-after-free in __skb_datagram_iter+0x6f8/0x760 net/core/datagram.c:412
Read of size 4 at addr ffff88810f8781b0 by task syz-executor.0/8713

CPU: 0 PID: 8713 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-16159-g3ca112b71f35 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x155/0x1c0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0x15d/0x540 mm/kasan/report.c:475
 kasan_report+0x14e/0x180 mm/kasan/report.c:588
 __asan_report_load4_noabort+0x18/0x20 mm/kasan/report_generic.c:380
 skb_headlen include/linux/skbuff.h:2405 [inline]
 __skb_datagram_iter+0x6f8/0x760 net/core/datagram.c:412
 skb_copy_datagram_iter+0x47/0x180 net/core/datagram.c:546
 skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline]
 unix_stream_read_actor+0x74/0xc0 net/unix/af_unix.c:2866
 unix_stream_recv_urg+0x1b4/0x300 net/unix/af_unix.c:2587
 unix_stream_read_generic+0x2176/0x2270 net/unix/af_unix.c:2666
 unix_stream_recvmsg+0x226/0x2b0 net/unix/af_unix.c:2903
 sock_recvmsg_nosec net/socket.c:1044 [inline]
 sock_recvmsg net/socket.c:1066 [inline]
 ____sys_recvmsg+0x296/0x570 net/socket.c:2803
 ___sys_recvmsg net/socket.c:2845 [inline]
 __sys_recvmsg+0x2f0/0x3d0 net/socket.c:2875
 __do_sys_recvmsg net/socket.c:2885 [inline]
 __se_sys_recvmsg net/socket.c:2882 [inline]
 __x64_sys_recvmsg+0x83/0x90 net/socket.c:2882
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0xe0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f708b47cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f708c1950c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f708b59c120 RCX: 00007f708b47cae9
RDX: 0000000040010083 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00007f708b4c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f708b59c120 R15: 00007fff326ae5a8
 </TASK>

Allocated by task 8712:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x23/0x30 mm/kasan/generic.c:511
 __kasan_slab_alloc+0x6d/0x80 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x68/0x2f0 mm/slab.h:763
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x17c/0x320 mm/slub.c:3523
 __alloc_skb+0x17b/0x400 net/core/skbuff.c:641
 alloc_skb include/linux/skbuff.h:1286 [inline]
 alloc_skb_with_frags+0xd1/0x6f0 net/core/skbuff.c:6331
 sock_alloc_send_pskb+0x919/0xa50 net/core/sock.c:2780
 sock_alloc_send_skb include/net/sock.h:1884 [inline]
 queue_oob+0x106/0x8e0 net/unix/af_unix.c:2147
 unix_stream_sendmsg+0xfd0/0x1220 net/unix/af_unix.c:2301
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x5a6/0x8a0 net/socket.c:2584
 ___sys_sendmsg net/socket.c:2638 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x83/0x90 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0xe0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Freed by task 8712:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2c/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free+0x131/0x180 mm/kasan/common.c:236
 __kasan_slab_free+0x15/0x20 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1800 [inline]
 slab_free_freelist_hook mm/slub.c:1826 [inline]
 slab_free mm/slub.c:3809 [inline]
 kmem_cache_free+0x299/0x520 mm/slub.c:3831
 kfree_skbmem+0x104/0x170
 __kfree_skb net/core/skbuff.c:1073 [inline]
 consume_skb+0xc3/0x270 net/core/skbuff.c:1288
 queue_oob+0x530/0x8e0 net/unix/af_unix.c:2178
 unix_stream_sendmsg+0xfd0/0x1220 net/unix/af_unix.c:2301
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x5a6/0x8a0 net/socket.c:2584
 ___sys_sendmsg net/socket.c:2638 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x83/0x90 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0xe0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff88810f878140
 which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 112 bytes inside of
 freed 232-byte region [ffff88810f878140, ffff88810f878228)

The buggy address belongs to the physical page:
page:ffffea00043e1e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10f878
flags: 0x4000000000000800(slab|zone=1)
page_type: 0xffffffff()
raw: 4000000000000800 ffff888108965000 ffffea00043e5000 dead000000000002
raw: 0000000000000000 00000000000c000c 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 5259, tgid 5257 (syz-executor.0), ts 119760344357, free_ts 118563991656
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x223/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1544 [inline]
 get_page_from_freelist+0x35b8/0x3680 mm/page_alloc.c:3312
 __alloc_pages+0x3e7/0x890 mm/page_alloc.c:4568
 allocate_slab mm/slub.c:2017 [inline]
 new_slab+0xce/0x4d0 mm/slub.c:2070
 ___slab_alloc+0x789/0xc50 mm/slub.c:3223
 __slab_alloc mm/slub.c:3322 [inline]
 __slab_alloc_node mm/slub.c:3375 [inline]
 slab_alloc_node mm/slub.c:3468 [inline]
 kmem_cache_alloc_node+0x1f5/0x320 mm/slub.c:3523
 __alloc_skb+0x17b/0x400 net/core/skbuff.c:641
 alloc_skb include/linux/skbuff.h:1286 [inline]
 alloc_skb_with_frags+0xd1/0x6f0 net/core/skbuff.c:6331
 sock_alloc_send_pskb+0x919/0xa50 net/core/sock.c:2780
 sock_alloc_send_skb include/net/sock.h:1884 [inline]
 queue_oob+0x106/0x8e0 net/unix/af_unix.c:2147
 unix_stream_sendmsg+0xfd0/0x1220 net/unix/af_unix.c:2301
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x5a6/0x8a0 net/socket.c:2584
 ___sys_sendmsg net/socket.c:2638 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x83/0x90 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0xe0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1137 [inline]
 free_unref_page_prepare+0x498/0x6c0 mm/page_alloc.c:2347
 free_unref_page_list+0xfb/0x790 mm/page_alloc.c:2533
 release_pages+0xe23/0xe80 mm/swap.c:1042
 free_pages_and_swap_cache+0x92/0xa0 mm/swap_state.c:316
 tlb_batch_pages_flush mm/mmu_gather.c:98 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:293 [inline]
 tlb_flush_mmu+0x383/0x500 mm/mmu_gather.c:300
 tlb_finish_mmu+0xdb/0x1f0 mm/mmu_gather.c:392
 exit_mmap+0x493/0x9f0 mm/mmap.c:3321
 __mmput+0x95/0x310 kernel/fork.c:1349
 mmput+0x63/0x80 kernel/fork.c:1371
 exit_mm kernel/exit.c:567 [inline]
 do_exit+0xa9b/0x2940 kernel/exit.c:858
 do_group_exit+0x21e/0x2e0 kernel/exit.c:1021
 get_signal+0x1727/0x18b0 kernel/signal.c:2904
 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:309
 exit_to_user_mode_loop+0x74/0xa0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x2a/0x140 kernel/entry/common.c:296

Memory state around the buggy address:
 ffff88810f878080: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff88810f878100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
>ffff88810f878180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88810f878200: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
 ffff88810f878280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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