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BUG: KASAN: slab-out-of-bounds in csum_partial_copy_nocheck include/net/checksum.h:53 [inline]
BUG: KASAN: slab-out-of-bounds in skb_copy_and_csum_bits+0x433/0x9c0 net/core/skbuff.c:3620
Write of size 1284 at addr ffff8880619f52e0 by task syz.1.39/6110

CPU: 1 UID: 0 PID: 6110 Comm: syz.1.39 Not tainted 6.12.0-rc5-next-20241030-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:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106
 csum_partial_copy_nocheck include/net/checksum.h:53 [inline]
 skb_copy_and_csum_bits+0x433/0x9c0 net/core/skbuff.c:3620
 __ip6_append_data+0x3075/0x4380 net/ipv6/ip6_output.c:1691
 ip6_append_data+0x264/0x3a0 net/ipv6/ip6_output.c:1852
 l2tp_ip6_sendmsg+0x17a5/0x2020 net/l2tp/l2tp_ip6.c:660
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg+0x1a6/0x270 net/socket.c:744
 sock_sendmsg+0x134/0x200 net/socket.c:767
 splice_to_socket+0xa10/0x10b0 fs/splice.c:889
 do_splice_from fs/splice.c:941 [inline]
 do_splice+0xd68/0x18e0 fs/splice.c:1354
 __do_splice fs/splice.c:1436 [inline]
 __do_sys_splice fs/splice.c:1652 [inline]
 __se_sys_splice+0x331/0x4a0 fs/splice.c:1634
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faf6977e719
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007faf67bd5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00007faf69936130 RCX: 00007faf6977e719
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007faf697f132e R08: 0000000000008004 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007faf69936130 R15: 00007ffd90eed5e8
 </TASK>

Allocated by task 6110:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4104 [inline]
 slab_alloc_node mm/slub.c:4153 [inline]
 kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4205
 kmalloc_reserve+0xa8/0x2a0 net/core/skbuff.c:587
 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678
 alloc_skb include/linux/skbuff.h:1322 [inline]
 __ip6_append_data+0x2e49/0x4380 net/ipv6/ip6_output.c:1665
 ip6_append_data+0x264/0x3a0 net/ipv6/ip6_output.c:1852
 l2tp_ip6_sendmsg+0x17a5/0x2020 net/l2tp/l2tp_ip6.c:660
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg+0x1a6/0x270 net/socket.c:744
 sock_sendmsg+0x134/0x200 net/socket.c:767
 splice_to_socket+0xa10/0x10b0 fs/splice.c:889
 do_splice_from fs/splice.c:941 [inline]
 do_splice+0xd68/0x18e0 fs/splice.c:1354
 __do_splice fs/splice.c:1436 [inline]
 __do_sys_splice fs/splice.c:1652 [inline]
 __se_sys_splice+0x331/0x4a0 fs/splice.c:1634
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880619f5200
 which belongs to the cache skbuff_small_head of size 640
The buggy address is located 224 bytes inside of
 allocated 640-byte region [ffff8880619f5200, ffff8880619f5480)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x619f4
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888141ab6a00 ffffea00018c3500 0000000000000002
raw: 0000000000000000 0000000080150015 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff888141ab6a00 ffffea00018c3500 0000000000000002
head: 0000000000000000 0000000080150015 00000001f5000000 0000000000000000
head: 00fff00000000002 ffffea0001867d01 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5944, tgid 5943 (syz.0.10), ts 85917120626, free_ts 26340481575
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1541
 prep_new_page mm/page_alloc.c:1549 [inline]
 get_page_from_freelist+0x3725/0x3870 mm/page_alloc.c:3495
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4771
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x140 mm/slub.c:2408
 allocate_slab+0x5a/0x2f0 mm/slub.c:2574
 new_slab mm/slub.c:2627 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3815
 __slab_alloc+0x58/0xa0 mm/slub.c:3905
 __slab_alloc_node mm/slub.c:3980 [inline]
 slab_alloc_node mm/slub.c:4141 [inline]
 kmem_cache_alloc_node_noprof+0x269/0x380 mm/slub.c:4205
 kmalloc_reserve+0xa8/0x2a0 net/core/skbuff.c:587
 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678
 skb_copy+0x19d/0x9c0 net/core/skbuff.c:2159
 mac80211_hwsim_tx_frame_no_nl+0x106b/0x18d0 drivers/net/wireless/virtual/mac80211_hwsim.c:1866
 mac80211_hwsim_tx_frame+0x1cc/0x220 drivers/net/wireless/virtual/mac80211_hwsim.c:2215
 mac80211_hwsim_beacon_tx+0x3bf/0x850 drivers/net/wireless/virtual/mac80211_hwsim.c:2315
 __iterate_interfaces+0x297/0x570 net/mac80211/util.c:775
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1112 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2678
 free_contig_range+0x152/0x550 mm/page_alloc.c:6786
 destroy_args+0x92/0x910 mm/debug_vm_pgtable.c:1017
 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1397
 do_one_initcall+0x248/0x880 init/main.c:1266
 do_initcall_level+0x157/0x210 init/main.c:1328
 do_initcalls+0x3f/0x80 init/main.c:1344
 kernel_init_freeable+0x435/0x5d0 init/main.c:1577
 kernel_init+0x1d/0x2b0 init/main.c:1466
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff8880619f5380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880619f5400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880619f5480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff8880619f5500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880619f5580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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