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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 1144 at addr ffff88801233c924 by task syz.2.1050/12603

CPU: 0 UID: 0 PID: 12603 Comm: syz.2.1050 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
 __ip_append_data+0x2fc1/0x40f0 net/ipv4/ip_output.c:1159
 ip_append_data+0x14c/0x190 net/ipv4/ip_output.c:1375
 udp_sendmsg+0x52c/0x2a50 net/ipv4/udp.c:1298
 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: 0033:0x7ff48317e719
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:00007ff4815b4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00007ff483336130 RCX: 00007ff48317e719
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007ff4831f132e R08: 0000000000007151 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007ff483336130 R15: 00007ffdb0a8c008
 </TASK>

Allocated by task 12603:
 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]
 __ip_append_data+0x2da7/0x40f0 net/ipv4/ip_output.c:1134
 ip_append_data+0x14c/0x190 net/ipv4/ip_output.c:1375
 udp_sendmsg+0x52c/0x2a50 net/ipv4/udp.c:1298
 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 ffff88801233c900
 which belongs to the cache skbuff_small_head of size 640
The buggy address is located 36 bytes inside of
 allocated 640-byte region [ffff88801233c900, ffff88801233cb80)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1233c
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 ffff88823be06f00 ffffea0001b95500 dead000000000002
raw: 0000000000000000 0000000080150015 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88823be06f00 ffffea0001b95500 dead000000000002
head: 0000000000000000 0000000080150015 00000001f5000000 0000000000000000
head: 00fff00000000002 ffffea000048cf01 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5223, tgid 5223 (udevadm), ts 34807779823, free_ts 29616729268
 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
 alloc_skb include/linux/skbuff.h:1322 [inline]
 alloc_uevent_skb+0x74/0x230 lib/kobject_uevent.c:289
 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline]
 kobject_uevent_net_broadcast+0x2fd/0x580 lib/kobject_uevent.c:410
 kobject_uevent_env+0x57d/0x8e0 lib/kobject_uevent.c:608
 kobject_synth_uevent+0x4ef/0xae0 lib/kobject_uevent.c:207
 store_uevent+0x16/0x30 kernel/module/main.c:950
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_reserved_page+0xcc/0x120 mm/page_alloc.c:5897
 free_reserved_area+0x51/0xf0 mm/page_alloc.c:5883
 free_init_pages arch/x86/mm/init.c:932 [inline]
 free_kernel_image_pages arch/x86/mm/init.c:948 [inline]
 free_initmem+0x9a/0x110 arch/x86/mm/init.c:975
 kernel_init+0x31/0x2b0 init/main.c:1475
 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:
 ffff88801233ca80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88801233cb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88801233cb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88801233cc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801233cc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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