syzbot

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BUG: KMSAN: uninit-value in do_slab_free mm/slub.c:2954 [inline]
BUG: KMSAN: uninit-value in slab_free mm/slub.c:2977 [inline]
BUG: KMSAN: uninit-value in kfree+0x5d8/0x29d0 mm/slub.c:3939
CPU: 1 PID: 6577 Comm: udevd Not tainted 4.18.0-rc8+ #34
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+0x17c/0x1c0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:982
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
 do_slab_free mm/slub.c:2954 [inline]
 slab_free mm/slub.c:2977 [inline]
 kfree+0x5d8/0x29d0 mm/slub.c:3939
 kernfs_put_open_node+0x383/0x430 fs/kernfs/file.c:614
 kernfs_fop_release+0x295/0x3b0 fs/kernfs/file.c:780
 __fput+0x458/0xa30 fs/file_table.c:209
 ____fput+0x37/0x40 fs/file_table.c:243
 task_work_run+0x22e/0x2b0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:192 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:166 [inline]
 prepare_exit_to_usermode+0x339/0x410 arch/x86/entry/common.c:197
 syscall_return_slowpath+0xdb/0x700 arch/x86/entry/common.c:268
 do_syscall_64+0x1ab/0x220 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x7f09062182b0
Code: 40 75 0b 31 c0 48 83 c4 08 e9 0c ff ff ff 48 8d 3d c5 32 08 00 e8 c0 07 02 00 83 3d 45 a3 2b 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ce 8a 01 00 48 89 04 24 
RSP: 002b:00007ffe28d95778 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000dcb0b0 RCX: 00007f09062182b0
RDX: 0000000000dcb190 RSI: 0000000000000001 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007f0906b107a0 R09: 0000000000000000
R10: 0000000000db24d0 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000dcb0b0 R14: 0000000000000006 R15: 0000000000000707

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:271 [inline]
 kmsan_internal_chain_origin+0x128/0x210 mm/kmsan/kmsan.c:573
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:483
 ___slab_alloc+0x1e02/0x1fa0 mm/slub.c:2570
 __slab_alloc mm/slub.c:2623 [inline]
 slab_alloc_node mm/slub.c:2686 [inline]
 slab_alloc mm/slub.c:2728 [inline]
 __kmalloc+0x2d8/0x350 mm/slub.c:3776
 kmalloc include/linux/slab.h:518 [inline]
 kzalloc include/linux/slab.h:707 [inline]
 sctp_add_bind_addr+0xbd/0x610 net/sctp/bind_addr.c:159
 sctp_copy_local_addr_list+0x4e1/0x610 net/sctp/protocol.c:180
 sctp_copy_one_addr+0x213/0xc30 net/sctp/bind_addr.c:449
 sctp_bind_addr_copy+0x246/0x940 net/sctp/bind_addr.c:71
 sctp_assoc_set_bind_addr_from_ep+0x21b/0x280 net/sctp/associola.c:1585
 sctp_sendmsg_new_asoc net/sctp/socket.c:1744 [inline]
 sctp_sendmsg+0x4716/0x5f60 net/sctp/socket.c:2097
 inet_sendmsg+0x49a/0x740 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg net/socket.c:652 [inline]
 __sys_sendto+0x6a3/0x7c0 net/socket.c:1798
 __do_sys_sendto net/socket.c:1810 [inline]
 __se_sys_sendto net/socket.c:1806 [inline]
 __x64_sys_sendto+0x1a1/0x210 net/socket.c:1806
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
 kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
 __kmalloc+0x13a/0x350 mm/slub.c:3782
 kmalloc include/linux/slab.h:518 [inline]
 sock_alloc_inode+0xb9/0x2a0 net/socket.c:247
 alloc_inode fs/inode.c:210 [inline]
 new_inode_pseudo+0x95/0x410 fs/inode.c:895
 sock_alloc net/socket.c:568 [inline]
 __sock_create+0x383/0xf10 net/socket.c:1251
 sock_create net/socket.c:1327 [inline]
 __sys_socket+0x175/0x630 net/socket.c:1357
 __do_sys_socket net/socket.c:1366 [inline]
 __se_sys_socket net/socket.c:1364 [inline]
 __x64_sys_socket+0xd8/0x120 net/socket.c:1364
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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