=====================================================
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: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+0xef3/0x33f0 lib/iov_iter.c:197
 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: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+0xef3/0x33f0 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+0x196/0x12c0 net/core/datagram.c:402
 skb_copy_datagram_iter+0x5b/0x1e0 net/core/datagram.c:535
 skb_copy_datagram_msg include/linux/skbuff.h:4217 [inline]
 packet_recvmsg+0xe2b/0x24e0 net/packet/af_packet.c:3472
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 sock_recvmsg+0x2df/0x390 net/socket.c:1100
 ____sys_recvmsg+0x193/0x610 net/socket.c:2812
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2854
 __sys_recvmsg+0x1a7/0x300 net/socket.c:2887
 __compat_sys_recvmsg net/compat.c:374 [inline]
 __do_compat_sys_recvmsg net/compat.c:381 [inline]
 __se_compat_sys_recvmsg net/compat.c:378 [inline]
 __ia32_compat_sys_recvmsg+0xa4/0x100 net/compat.c:378
 ia32_sys_call+0x361a/0x4340 arch/x86/include/generated/asm/syscalls_32.h:373
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x154/0x330 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x38/0x80 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:
 slab_post_alloc_hook mm/slub.c:4960 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586
 __alloc_skb+0x805/0x1040 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6712
 sock_alloc_send_pskb+0xacc/0xc60 net/core/sock.c:2995
 sock_alloc_send_skb include/net/sock.h:1885 [inline]
 __ip_append_data+0x4e9f/0x7160 net/ipv4/ip_output.c:1127
 ip_append_data+0x145/0x220 net/ipv4/ip_output.c:1378
 udp_sendmsg+0x4e1/0x3370 net/ipv4/udp.c:1510
 inet_sendmsg+0x1ef/0x2a0 net/ipv4/af_inet.c:859
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x278/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x863/0xcf0 net/socket.c:2592
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
 __sys_sendmmsg+0x3bf/0x7c0 net/socket.c:2728
 __compat_sys_sendmmsg net/compat.c:360 [inline]
 __do_compat_sys_sendmmsg net/compat.c:367 [inline]
 __se_compat_sys_sendmmsg net/compat.c:364 [inline]
 __ia32_compat_sys_sendmmsg+0xd2/0x160 net/compat.c:364
 ia32_sys_call+0x3cd2/0x4340 arch/x86/include/generated/asm/syscalls_32.h:346
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x154/0x330 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x38/0x80 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 24-31 of 60 are uninitialized
Memory access of size 60 starts at ffff88801e5ce1a0
Data copied to user address 00000000800014c0

CPU: 0 UID: 0 PID: 3732 Comm: syz.8.9373 Tainted: G        W    L      syzkaller #0 PREEMPT(none) 
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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