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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+0x364/0x2520 lib/iov_iter.c:186
 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+0x364/0x2520 lib/iov_iter.c:186
 copy_to_iter include/linux/uio.h:197 [inline]
 simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:532
 __skb_datagram_iter+0x123/0xdc0 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+0x2167/0x2ae0 drivers/net/tun.c:2243
 tun_chr_read_iter+0x3f0/0x670 drivers/net/tun.c:2267
 call_read_iter include/linux/fs.h:2014 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x8f6/0xe00 fs/read_write.c:470
 ksys_read+0x20f/0x4c0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x93/0xd0 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 pskb_expand_head+0x305/0x1a00 net/core/skbuff.c:2106
 __skb_cow include/linux/skbuff.h:3586 [inline]
 skb_cow_head include/linux/skbuff.h:3620 [inline]
 ip_tunnel_xmit+0x36ef/0x3e80 net/ipv4/ip_tunnel.c:824
 __gre_xmit+0x170/0x1b0 net/ipv4/ip_gre.c:469
 erspan_xmit+0x132e/0x1e40 net/ipv4/ip_gre.c:717
 __netdev_start_xmit include/linux/netdevice.h:4918 [inline]
 netdev_start_xmit include/linux/netdevice.h:4932 [inline]
 xmit_one net/core/dev.c:3545 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3561
 sch_direct_xmit+0x3c5/0xd40 net/sched/sch_generic.c:342
 __dev_xmit_skb net/core/dev.c:3772 [inline]
 __dev_queue_xmit+0x2de4/0x5130 net/core/dev.c:4312
 dev_queue_xmit include/linux/netdevice.h:3112 [inline]
 neigh_resolve_output+0x99a/0xab0 net/core/neighbour.c:1556
 neigh_output include/net/neighbour.h:542 [inline]
 ip_finish_output2+0x1931/0x1b40 net/ipv4/ip_output.c:235
 __ip_finish_output+0x266/0x720
 ip_finish_output+0x4b/0x550 net/ipv4/ip_output.c:323
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip_output+0x15f/0x3e0 net/ipv4/ip_output.c:433
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0xe9/0x140 net/ipv4/ip_output.c:129
 igmpv3_sendpack+0x2a6/0x5b0 net/ipv4/igmp.c:425
 igmpv3_send_cr net/ipv4/igmp.c:721 [inline]
 igmp_ifc_timer_expire+0x1410/0x1cc0 net/ipv4/igmp.c:811
 call_timer_fn+0x45/0x570 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x850/0xf60 kernel/time/timer.c:2022
 run_timer_softirq+0x26/0x40 kernel/time/timer.c:2035
 __do_softirq+0x1b7/0x7c3 kernel/softirq.c:553

Uninit was created at:
 slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 __kmem_cache_alloc_node+0x5c9/0x970 mm/slub.c:3517
 __do_kmalloc_node mm/slab_common.c:1006 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:1027
 kmalloc_reserve+0x249/0x4a0 net/core/skbuff.c:582
 __alloc_skb+0x318/0x740 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1286 [inline]
 igmpv3_newpack+0x189/0x13e0 net/ipv4/igmp.c:360
 add_grhead+0x83/0x430 net/ipv4/igmp.c:441
 add_grec+0x1e87/0x2100 net/ipv4/igmp.c:575
 igmpv3_send_cr net/ipv4/igmp.c:712 [inline]
 igmp_ifc_timer_expire+0x11bc/0x1cc0 net/ipv4/igmp.c:811
 call_timer_fn+0x45/0x570 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x850/0xf60 kernel/time/timer.c:2022
 run_timer_softirq+0x26/0x40 kernel/time/timer.c:2035
 __do_softirq+0x1b7/0x7c3 kernel/softirq.c:553

Bytes 38-41 of 104 are uninitialized
Memory access of size 104 starts at ffff8880370360c0
Data copied to user address 00007f4f33cbf960

CPU: 0 PID: 5842 Comm: syz-executor.0 Tainted: G        W          6.7.0-rc1-syzkaller-00344-g037266a5f723 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
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