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BUG: KASAN: use-after-free in memcpy include/linux/string.h:447 [inline]
BUG: KASAN: use-after-free in skb_copy_from_linear_data_offset include/linux/skbuff.h:3676 [inline]
BUG: KASAN: use-after-free in skb_segment+0x14ba/0x37a0 net/core/skbuff.c:3996
Read of size 2324 at addr ffff888011ddf2f7 by task syz-executor.1/10100

CPU: 0 PID: 10100 Comm: syz-executor.1 Not tainted 5.11.0-rc3-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:396 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413
 check_memory_region_inline mm/kasan/generic.c:179 [inline]
 check_memory_region+0x13d/0x180 mm/kasan/generic.c:185
 memcpy+0x20/0x60 mm/kasan/shadow.c:64
 memcpy include/linux/string.h:447 [inline]
 skb_copy_from_linear_data_offset include/linux/skbuff.h:3676 [inline]
 skb_segment+0x14ba/0x37a0 net/core/skbuff.c:3996
 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:00007f08206a3c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045e219
RDX: 000000000000fc13 RSI: 0000000020000280 RDI: 0000000000000004
RBP: 000000000119bfd8 R08: 0000000000000000 R09: 000000000000002f
R10: 0000000000000800 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007ffd7436ea4f R14: 00007f08206a49c0 R15: 000000000119bf8c

Allocated by task 9818:
 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:401 [inline]
 ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:429
 kasan_slab_alloc include/linux/kasan.h:205 [inline]
 slab_post_alloc_hook mm/slab.h:512 [inline]
 slab_alloc_node mm/slub.c:2891 [inline]
 slab_alloc mm/slub.c:2899 [inline]
 kmem_cache_alloc+0x1c6/0x440 mm/slub.c:2904
 kmem_cache_zalloc include/linux/slab.h:672 [inline]
 seq_open+0x57/0x180 fs/seq_file.c:60
 single_open+0xf9/0x1e0 fs/seq_file.c:569
 do_dentry_open+0x4b9/0x11b0 fs/open.c:817
 do_open fs/namei.c:3254 [inline]
 path_openat+0x1b9a/0x2730 fs/namei.c:3371
 do_filp_open+0x17e/0x3c0 fs/namei.c:3398
 do_sys_openat2+0x16d/0x420 fs/open.c:1172
 do_sys_open fs/open.c:1188 [inline]
 __do_sys_open fs/open.c:1196 [inline]
 __se_sys_open fs/open.c:1192 [inline]
 __x64_sys_open+0x119/0x1c0 fs/open.c:1192
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 9818:
 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:356
 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:362
 kasan_slab_free include/linux/kasan.h:188 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580
 slab_free mm/slub.c:3142 [inline]
 kmem_cache_free+0x82/0x350 mm/slub.c:3158
 seq_release fs/seq_file.c:353 [inline]
 single_release+0x84/0xb0 fs/seq_file.c:600
 __fput+0x283/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x190 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff888011ddf250
 which belongs to the cache seq_file of size 232
The buggy address is located 167 bytes inside of
 232-byte region [ffff888011ddf250, ffff888011ddf338)
The buggy address belongs to the page:
page:0000000006f38197 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11ddf
flags: 0xfff00000000200(slab)
raw: 00fff00000000200 ffffea0000710380 0000000500000005 ffff8880101bedc0
raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888011ddf180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888011ddf200: fb fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb
>ffff888011ddf280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff888011ddf300: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa
 ffff888011ddf380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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