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BUG: KASAN: slab-out-of-bounds in memcpy include/linux/fortify-string.h:191 [inline]
BUG: KASAN: slab-out-of-bounds in skb_copy_from_linear_data_offset include/linux/skbuff.h:3676 [inline]
BUG: KASAN: slab-out-of-bounds in skb_segment+0x14ba/0x37a0 net/core/skbuff.c:4000
Read of size 2324 at addr ffff888013ab72f7 by task syz-executor.2/22753

CPU: 0 PID: 22753 Comm: syz-executor.2 Not tainted 5.11.0-rc4-next-20210119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:397 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:414
 check_region_inline mm/kasan/generic.c:180 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:186
 memcpy+0x20/0x60 mm/kasan/shadow.c:65
 memcpy include/linux/fortify-string.h:191 [inline]
 skb_copy_from_linear_data_offset include/linux/skbuff.h:3676 [inline]
 skb_segment+0x14ba/0x37a0 net/core/skbuff.c:4000
 udp4_ufo_fragment+0x4ae/0x700 net/ipv4/udp_offload.c:363
 inet_gso_segment+0x502/0x1110 net/ipv4/af_inet.c:1378
 skb_mac_gso_segment+0x26e/0x530 net/core/dev.c:3326
 __skb_gso_segment+0x330/0x6e0 net/core/dev.c:3399
 skb_gso_segment include/linux/netdevice.h:4708 [inline]
 validate_xmit_skb+0x69e/0xee0 net/core/dev.c:3644
 __dev_queue_xmit+0x988/0x2dd0 net/core/dev.c:4142
 packet_snd net/packet/af_packet.c:3006 [inline]
 packet_sendmsg+0x2406/0x52a0 net/packet/af_packet.c:3031
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 __sys_sendto+0x21c/0x320 net/socket.c:1975
 __do_sys_sendto net/socket.c:1987 [inline]
 __se_sys_sendto net/socket.c:1983 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:1983
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e219
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdd27f8ac68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045e219
RDX: 000000000000fc13 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 000000000119bfd8 R08: 0000000000000000 R09: 000000000000002f
R10: 0000000000000800 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007ffe06370c3f R14: 00007fdd27f8b9c0 R15: 000000000119bf8c

Allocated by task 20946:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:403 [inline]
 ____kasan_kmalloc mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc.constprop.0+0xa0/0xd0 mm/kasan/common.c:406
 kmalloc include/linux/slab.h:561 [inline]
 tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path2_perm+0x264/0x6b0 security/tomoyo/file.c:922
 tomoyo_path_rename+0xd2/0x130 security/tomoyo/tomoyo.c:279
 security_path_rename+0x1b5/0x2e0 security/security.c:1145
 do_renameat2+0x95f/0xc00 fs/namei.c:4451
 __do_sys_rename fs/namei.c:4506 [inline]
 __se_sys_rename fs/namei.c:4504 [inline]
 __x64_sys_rename+0x7d/0xa0 fs/namei.c:4504
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 20946:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
 ____kasan_slab_free.part.0+0xe1/0x110 mm/kasan/common.c:364
 kasan_slab_free include/linux/kasan.h:192 [inline]
 slab_free_hook mm/slub.c:1548 [inline]
 slab_free_freelist_hook+0x82/0x1d0 mm/slub.c:1586
 slab_free mm/slub.c:3157 [inline]
 kfree+0xe5/0x7b0 mm/slub.c:4198
 tomoyo_realpath_from_path+0x191/0x620 security/tomoyo/realpath.c:291
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path2_perm+0x264/0x6b0 security/tomoyo/file.c:922
 tomoyo_path_rename+0xd2/0x130 security/tomoyo/tomoyo.c:279
 security_path_rename+0x1b5/0x2e0 security/security.c:1145
 do_renameat2+0x95f/0xc00 fs/namei.c:4451
 __do_sys_rename fs/namei.c:4506 [inline]
 __se_sys_rename fs/namei.c:4504 [inline]
 __x64_sys_rename+0x7d/0xa0 fs/namei.c:4504
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff888013ab6000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 759 bytes to the right of
 4096-byte region [ffff888013ab6000, ffff888013ab7000)
The buggy address belongs to the page:
page:00000000629f5ea7 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x13ab0
head:00000000629f5ea7 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010042140
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888013ab7180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888013ab7200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888013ab7280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                             ^
 ffff888013ab7300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888013ab7380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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