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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak in iterate_ubuf include/linux/iov_iter.h:29 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:271 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x366/0x24b0 lib/iov_iter.c:185
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:29 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x366/0x24b0 lib/iov_iter.c:185
 copy_to_iter include/linux/uio.h:196 [inline]
 simple_copy_to_iter net/core/datagram.c:532 [inline]
 __skb_datagram_iter+0x185/0x1000 net/core/datagram.c:420
 skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:546
 tun_put_user drivers/net/tun.c:2166 [inline]
 tun_do_read+0x25c2/0x2d20 drivers/net/tun.c:2245
 tun_chr_read_iter+0x3f0/0x670 drivers/net/tun.c:2269
 call_read_iter include/linux/fs.h:2114 [inline]
 new_sync_read fs/read_write.c:395 [inline]
 vfs_read+0xda3/0xef0 fs/read_write.c:476
 ksys_read+0x20f/0x4c0 fs/read_write.c:619
 __do_sys_read fs/read_write.c:629 [inline]
 __se_sys_read fs/read_write.c:627 [inline]
 __x64_sys_read+0x93/0xe0 fs/read_write.c:627
 x64_sys_call+0x304d/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 pskb_expand_head+0x30f/0x19d0 net/core/skbuff.c:2271
 skb_expand_head+0x45d/0x890 net/core/skbuff.c:2435
 ip_finish_output2+0xd9d/0x1b70 net/ipv4/ip_output.c:216
 __ip_finish_output+0x287/0x810
 ip_finish_output+0x4b/0x550 net/ipv4/ip_output.c:323
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip_output+0x15f/0x3f0 net/ipv4/ip_output.c:433
 dst_output include/net/dst.h:450 [inline]
 ip_local_out net/ipv4/ip_output.c:129 [inline]
 __ip_queue_xmit+0x1e93/0x2030 net/ipv4/ip_output.c:535
 sctp_v4_xmit+0x6a2/0xea0 net/sctp/protocol.c:1075
 sctp_packet_transmit+0x3fff/0x4310 net/sctp/output.c:653
 sctp_packet_singleton+0x342/0x440 net/sctp/outqueue.c:783
 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
 sctp_outq_flush+0x77c/0x6590 net/sctp/outqueue.c:1212
 sctp_outq_uncork+0x9c/0xb0 net/sctp/outqueue.c:764
 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]
 sctp_do_sm+0x8c49/0x93d0 net/sctp/sm_sideeffect.c:1169
 sctp_primitive_ASSOCIATE+0xc3/0x100 net/sctp/primitive.c:73
 sctp_sendmsg_to_asoc+0x179f/0x1f00 net/sctp/socket.c:1841
 sctp_sendmsg+0x32b9/0x4a80 net/sctp/socket.c:2031
 inet_sendmsg+0x25a/0x280 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x267/0x380 net/socket.c:745
 ____sys_sendmsg+0x877/0xb60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x4a0 net/socket.c:2674
 x64_sys_call+0xc4b/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3877 [inline]
 slab_alloc_node mm/slub.c:3918 [inline]
 __do_kmalloc_node mm/slub.c:4038 [inline]
 __kmalloc_node_track_caller+0x767/0x10c0 mm/slub.c:4059
 kmalloc_reserve+0x249/0x4a0 net/core/skbuff.c:599
 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1319 [inline]
 sctp_packet_transmit+0x454/0x4310 net/sctp/output.c:598
 sctp_packet_singleton+0x342/0x440 net/sctp/outqueue.c:783
 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
 sctp_outq_flush+0x77c/0x6590 net/sctp/outqueue.c:1212
 sctp_outq_uncork+0x9c/0xb0 net/sctp/outqueue.c:764
 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]
 sctp_do_sm+0x8c49/0x93d0 net/sctp/sm_sideeffect.c:1169
 sctp_primitive_ASSOCIATE+0xc3/0x100 net/sctp/primitive.c:73
 sctp_sendmsg_to_asoc+0x179f/0x1f00 net/sctp/socket.c:1841
 sctp_sendmsg+0x32b9/0x4a80 net/sctp/socket.c:2031
 inet_sendmsg+0x25a/0x280 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x267/0x380 net/socket.c:745
 ____sys_sendmsg+0x877/0xb60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x4a0 net/socket.c:2674
 x64_sys_call+0xc4b/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 38-41 of 580 are uninitialized
Memory access of size 580 starts at ffff888044c1f8b0
Data copied to user address 00007ffda248cde0

CPU: 0 PID: 5385 Comm: syz-executor.0 Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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