=====================================================
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/0x210 net/core/datagram.c:535
 skb_copy_datagram_msg include/linux/skbuff.h:4245 [inline]
 tcp_peek_sndq+0x12b/0x570 net/ipv4/tcp.c:1529
 tcp_recvmsg_locked+0x578e/0x5830 net/ipv4/tcp.c:2927
 tcp_recvmsg+0x2b6/0xad0 net/ipv4/tcp.c:2945
 inet_recvmsg+0x11a/0x570 net/ipv4/af_inet.c:896
 sock_recvmsg_nosec net/socket.c:1137 [inline]
 sock_recvmsg+0x22d/0x310 net/socket.c:1159
 ____sys_recvmsg+0x193/0x620 net/socket.c:2918
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2960
 do_recvmmsg+0x50b/0xdf0 net/socket.c:3047
 __sys_recvmmsg+0xf3/0x450 net/socket.c:3129
 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
 __ia32_compat_sys_recvmmsg_time32+0x102/0x1b0 net/compat.c:414
 ia32_sys_call+0x3ec3/0x4360 arch/x86/include/generated/asm/syscalls_32.h:338
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x195/0x470 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/syscall_32.c:332
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:370
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 __alloc_frozen_pages_noprof+0x6fa/0x1000 mm/page_alloc.c:5244
 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0x101/0x290 mm/mempolicy.c:2581
 skb_page_frag_refill+0x141/0x5e0 net/core/sock.c:3153
 sk_page_frag_refill+0x59/0x190 net/core/sock.c:3173
 tcp_sendmsg_locked+0x30d7/0x80b0 net/ipv4/tcp.c:1287
 tcp_sendmsg+0x4b/0x90 net/ipv4/tcp.c:1452
 inet_sendmsg+0x134/0x290 net/ipv4/af_inet.c:866
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x8bc/0xae0 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __ia32_sys_sendto+0x12f/0x200 net/socket.c:2268
 ia32_sys_call+0x372f/0x4360 arch/x86/include/generated/asm/syscalls_32.h:370
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x195/0x470 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/syscall_32.c:332
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:370
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Bytes 0-535 of 536 are uninitialized
Memory access of size 536 starts at ffff8880164a0000
Data copied to user address 0000000080004140

CPU: 1 UID: 0 PID: 9888 Comm: syz.5.1230 Tainted: G             L      syzkaller #0 PREEMPT(lazy) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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