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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:131 [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:30 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:330 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0xef3/0x3400 lib/iov_iter.c:197
 instrument_copy_to_user include/linux/instrumented.h:131 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0xef3/0x3400 lib/iov_iter.c:197
 copy_to_iter include/linux/uio.h:220 [inline]
 simple_copy_to_iter net/core/datagram.c:521 [inline]
 __skb_datagram_iter+0x7ce/0x12b0 net/core/datagram.c:435
 skb_copy_datagram_iter+0x5b/0x240 net/core/datagram.c:535
 skb_copy_datagram_msg include/linux/skbuff.h:4218 [inline]
 tcp_peek_sndq+0x12b/0x570 net/ipv4/tcp.c:1543
 tcp_recvmsg_locked+0x57ad/0x5850 net/ipv4/tcp.c:2961
 tcp_recvmsg+0x2bd/0xad0 net/ipv4/tcp.c:2980
 inet_recvmsg+0x15b/0x690 net/ipv4/af_inet.c:891
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 sock_recvmsg+0x22d/0x310 net/socket.c:1100
 ____sys_recvmsg+0x193/0x620 net/socket.c:2812
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2854
 do_recvmmsg+0x40e/0xdf0 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x383/0x500 net/socket.c:3039
 x64_sys_call+0x96d/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 __alloc_frozen_pages_noprof+0x6f7/0x1020 mm/page_alloc.c:5273
 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2484
 alloc_frozen_pages_noprof mm/mempolicy.c:2555 [inline]
 alloc_pages_noprof+0x101/0x280 mm/mempolicy.c:2575
 skb_page_frag_refill+0x34e/0x730 net/core/sock.c:3146
 sk_page_frag_refill+0x59/0x190 net/core/sock.c:3166
 tcp_sendmsg_locked+0x319a/0x7d30 net/ipv4/tcp.c:1300
 tcp_sendmsg+0x4b/0x90 net/ipv4/tcp.c:1465
 inet_sendmsg+0x134/0x290 net/ipv4/af_inet.c:859
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 __sys_sendto+0x8bc/0xae0 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0x130/0x200 net/socket.c:2209
 x64_sys_call+0x39a0/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 0-134 of 135 are uninitialized
Memory access of size 135 starts at ffff88812bcb8000
Data copied to user address 00002000000008c0

CPU: 1 UID: 0 PID: 7561 Comm: syz.0.497 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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