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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 839 at addr ffff88807e06aa24 by task syz.1.354/7166

CPU: 1 UID: 0 PID: 7166 Comm: syz.1.354 Not tainted 6.12.0-rc5-next-20241031-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+0x3e2/0x2a50 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]
 direct_splice_actor+0x11b/0x220 fs/splice.c:1164
 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x289/0x3e0 fs/splice.c:1233
 do_sendfile+0x561/0xe10 fs/read_write.c:1388
 __do_sys_sendfile64 fs/read_write.c:1455 [inline]
 __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1441
 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: 0033:0x7fe1ac37e719
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:00007fe1aa7f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fe1ac536058 RCX: 00007fe1ac37e719
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000005
RBP: 00007fe1ac3f132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000020000023890 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe1ac536058 R15: 00007ffcd1192628
 </TASK>

Allocated by task 7166:
 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+0x3e2/0x2a50 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]
 direct_splice_actor+0x11b/0x220 fs/splice.c:1164
 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x289/0x3e0 fs/splice.c:1233
 do_sendfile+0x561/0xe10 fs/read_write.c:1388
 __do_sys_sendfile64 fs/read_write.c:1455 [inline]
 __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1441
 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 ffff88807e06aa00
 which belongs to the cache skbuff_small_head of size 640
The buggy address is located 36 bytes inside of
 allocated 640-byte region [ffff88807e06aa00, ffff88807e06ac80)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e068
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 ffff88801ea99a00 ffffea000192eb00 dead000000000002
raw: 0000000000000000 0000000080150015 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801ea99a00 ffffea000192eb00 dead000000000002
head: 0000000000000000 0000000080150015 00000001f5000000 0000000000000000
head: 00fff00000000002 ffffea0001f81a01 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 5848, tgid 5848 (syz-executor), ts 83234804127, free_ts 83098552564
 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]
 nlmsg_new include/net/netlink.h:1015 [inline]
 netlink_ack+0x13f/0xa30 net/netlink/af_netlink.c:2488
 netlink_rcv_skb+0x262/0x430 net/netlink/af_netlink.c:2557
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
page last free pid 5221 tgid 5221 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
 __slab_free+0x31b/0x3d0 mm/slub.c:4509
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 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
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668
 netlink_sendmsg+0x638/0xcb0 net/netlink/af_netlink.c:1876
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2609
 ___sys_sendmsg net/socket.c:2663 [inline]
 __sys_sendmsg+0x292/0x380 net/socket.c:2692
 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

Memory state around the buggy address:
 ffff88807e06ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807e06ac00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807e06ac80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807e06ad00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807e06ad80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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