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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+0x366/0x2520 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+0x366/0x2520 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:2164 [inline]
 tun_do_read+0x21fc/0x2be0 drivers/net/tun.c:2243
 tun_chr_read_iter+0x3f0/0x670 drivers/net/tun.c:2267
 call_read_iter include/linux/fs.h:2102 [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
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1313 [inline]
 alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504
 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795
 sock_alloc_send_skb include/net/sock.h:1842 [inline]
 __ip_append_data+0x4c66/0x6960 net/ipv4/ip_output.c:1122
 ip_append_data+0x1f2/0x260 net/ipv4/ip_output.c:1365
 udp_sendmsg+0x4ea/0x3200 net/ipv4/udp.c:1274
 inet_sendmsg+0x1fc/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+0x903/0xb60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmmsg+0x3c4/0x950 net/socket.c:2724
 __do_sys_sendmmsg net/socket.c:2753 [inline]
 __se_sys_sendmmsg net/socket.c:2750 [inline]
 __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2750
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Bytes 38-41 of 92 are uninitialized
Memory access of size 92 starts at ffff888016c42f80
Data copied to user address 00007ffd1188af80

CPU: 0 PID: 12758 Comm: syz-executor.1 Tainted: G        W          6.9.0-rc1-syzkaller-00274-g486291a0e624 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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