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BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0xa9/0xb0 mm/kmsan/kmsan_hooks.c:257
CPU: 0 PID: 12322 Comm: syz-executor364 Not tainted 5.4.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108
 kmsan_internal_check_memory+0x178/0x440 mm/kmsan/kmsan.c:435
 kmsan_copy_to_user+0xa9/0xb0 mm/kmsan/kmsan_hooks.c:257
 copyout+0x16b/0x1f0 lib/iov_iter.c:145
 _copy_to_iter+0x35f/0x26f0 lib/iov_iter.c:616
 copy_to_iter include/linux/uio.h:138 [inline]
 simple_copy_to_iter+0x92/0xb0 net/core/datagram.c:515
 __skb_datagram_iter+0x24d/0xee0 net/core/datagram.c:423
 skb_copy_datagram_iter+0x29c/0x2b0 net/core/datagram.c:529
 tun_put_user drivers/net/tun.c:2144 [inline]
 tun_do_read+0x2522/0x2eb0 drivers/net/tun.c:2228
 tun_chr_read_iter+0x229/0x460 drivers/net/tun.c:2247
 call_read_iter include/linux/fs.h:1889 [inline]
 new_sync_read fs/read_write.c:414 [inline]
 __vfs_read+0xa67/0xc90 fs/read_write.c:427
 vfs_read+0x359/0x6f0 fs/read_write.c:461
 ksys_read+0x265/0x430 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read+0x92/0xb0 fs/read_write.c:595
 __x64_sys_read+0x4a/0x70 fs/read_write.c:595
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x402ae0
Code: 01 f0 ff ff 0f 83 a0 0d 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d cd 94 2d 00 00 75 14 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 74 0d 00 00 c3 48 83 ec 08 e8 da 02 00 00
RSP: 002b:00007ffcff159618 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000402ae0
RDX: 00000000000003e8 RSI: 00007ffcff159620 RDI: 00000000000000f0
RBP: 000000000001a7a6 R08: 0000000000000000 R09: 0000000000000004
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000403d70 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:149 [inline]
 kmsan_internal_chain_origin+0xb9/0x170 mm/kmsan/kmsan.c:317
 kmsan_memcpy_memmove_metadata+0x25c/0x2e0 mm/kmsan/kmsan.c:252
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:272
 __msan_memcpy+0x56/0x70 mm/kmsan/kmsan_instr.c:129
 pskb_expand_head+0x38a/0x19f0 net/core/skbuff.c:1637
 __skb_cow include/linux/skbuff.h:3118 [inline]
 skb_cow_head include/linux/skbuff.h:3152 [inline]
 batadv_skb_head_push+0x23c/0x360 net/batman-adv/soft-interface.c:75
 batadv_send_skb_packet+0x1a7/0x8c0 net/batman-adv/send.c:86
 batadv_send_broadcast_skb+0x76/0x90 net/batman-adv/send.c:127
 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x993/0xd50 net/batman-adv/bat_iv_ogm.c:1706
 process_one_work+0x1572/0x1ef0 kernel/workqueue.c:2269
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2415
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:149
 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:362 [inline]
 kmsan_alloc_page+0x140/0x330 mm/kmsan/kmsan_shadow.c:391
 __alloc_pages_nodemask+0x1421/0x5fd0 mm/page_alloc.c:4799
 __alloc_pages include/linux/gfp.h:498 [inline]
 __alloc_pages_node include/linux/gfp.h:511 [inline]
 alloc_pages_node include/linux/gfp.h:525 [inline]
 __page_frag_cache_refill mm/page_alloc.c:4874 [inline]
 page_frag_alloc+0x3ae/0x910 mm/page_alloc.c:4904
 __netdev_alloc_skb+0x672/0xb20 net/core/skbuff.c:455
 __netdev_alloc_skb_ip_align include/linux/skbuff.h:2799 [inline]
 netdev_alloc_skb_ip_align include/linux/skbuff.h:2809 [inline]
 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:558 [inline]
 batadv_iv_ogm_queue_add+0xf42/0x17b0 net/batman-adv/bat_iv_ogm.c:670
 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:829 [inline]
 batadv_iv_ogm_schedule+0xc1c/0x1080 net/batman-adv/bat_iv_ogm.c:865
 batadv_iv_send_outstanding_bat_ogm_packet+0xbc0/0xd50 net/batman-adv/bat_iv_ogm.c:1718
 process_one_work+0x1572/0x1ef0 kernel/workqueue.c:2269
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2415
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

Bytes 52-53 of 98 are uninitialized
Memory access of size 98 starts at ffff9e00e66d3440
Data copied to user address 00007ffcff159620
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