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BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:199 [inline]
BUG: KASAN: use-after-free in sock_cgroup_ptr include/linux/cgroup.h:836 [inline]
BUG: KASAN: use-after-free in inet_diag_bc_sk+0xb64/0xc70 net/ipv4/inet_diag.c:749
Read of size 8 at addr ffff8880923240e8 by task syz-executor.4/20394

CPU: 1 PID: 20394 Comm: syz-executor.4 Not tainted 5.7.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x315 mm/kasan/report.c:382
 __kasan_report.cold+0x35/0x4d mm/kasan/report.c:511
 kasan_report+0x33/0x50 mm/kasan/common.c:625
 __read_once_size include/linux/compiler.h:199 [inline]
 sock_cgroup_ptr include/linux/cgroup.h:836 [inline]
 inet_diag_bc_sk+0xb64/0xc70 net/ipv4/inet_diag.c:749
 inet_diag_dump_icsk+0xbe4/0x1306 net/ipv4/inet_diag.c:1061
 __inet_diag_dump+0x8d/0x240 net/ipv4/inet_diag.c:1113
 netlink_dump+0x50b/0xf50 net/netlink/af_netlink.c:2245
 __netlink_dump_start+0x63f/0x910 net/netlink/af_netlink.c:2353
 netlink_dump_start include/linux/netlink.h:246 [inline]
 inet_diag_handler_cmd+0x263/0x2c0 net/ipv4/inet_diag.c:1278
 __sock_diag_cmd net/core/sock_diag.c:233 [inline]
 sock_diag_rcv_msg+0x2fe/0x3e0 net/core/sock_diag.c:264
 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469
 sock_diag_rcv+0x26/0x40 net/core/sock_diag.c:275
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 sock_write_iter+0x289/0x3c0 net/socket.c:1004
 call_write_iter include/linux/fs.h:1907 [inline]
 do_iter_readv_writev+0x5a8/0x850 fs/read_write.c:694
 do_iter_write fs/read_write.c:999 [inline]
 do_iter_write+0x18b/0x600 fs/read_write.c:980
 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1072
 do_writev+0x27f/0x300 fs/read_write.c:1115
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c829
Code: 0d b7 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff6092bfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 000000000050d140 RCX: 000000000045c829
RDX: 0000000000000001 RSI: 00000000200000c0 RDI: 0000000000000007
RBP: 000000000078c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000d18 R14: 00000000004cb1f4 R15: 00007ff6092c06d4

Allocated by task 20278:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468
 __do_kmalloc mm/slab.c:3656 [inline]
 __kmalloc+0x161/0x7a0 mm/slab.c:3665
 kmalloc include/linux/slab.h:560 [inline]
 tomoyo_realpath_from_path+0xc2/0x620 security/tomoyo/realpath.c:252
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_number_perm+0x1c2/0x4d0 security/tomoyo/file.c:723
 security_file_ioctl+0x6c/0xb0 security/security.c:1460
 ksys_ioctl+0x50/0x180 fs/ioctl.c:757
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:770
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 20278:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 kasan_set_free_info mm/kasan/common.c:317 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 tomoyo_realpath_from_path+0x18f/0x620 security/tomoyo/realpath.c:289
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_number_perm+0x1c2/0x4d0 security/tomoyo/file.c:723
 security_file_ioctl+0x6c/0xb0 security/security.c:1460
 ksys_ioctl+0x50/0x180 fs/ioctl.c:757
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:770
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

The buggy address belongs to the object at ffff888092324000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 232 bytes inside of
 4096-byte region [ffff888092324000, ffff888092325000)
The buggy address belongs to the page:
page:ffffea000248c900 refcount:1 mapcount:0 mapping:000000006dcdd5c4 index:0x0 head:ffffea000248c900 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea000247ac88 ffffea000172d408 ffff8880aa002000
raw: 0000000000000000 ffff888092324000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888092323f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888092324000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888092324080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff888092324100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888092324180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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