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BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
CPU: 1 PID: 11152 Comm: rsyslogd Not tainted 5.3.0-rc7+ #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+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x13a/0x2b0 mm/kmsan/kmsan_report.c:108
 kmsan_internal_check_memory+0x187/0x4c0 mm/kmsan/kmsan.c:434
 kmsan_copy_to_user+0xa9/0xb0 mm/kmsan/kmsan_hooks.c:267
 _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
 copy_to_user include/linux/uaccess.h:174 [inline]
 syslog_print kernel/printk/printk.c:1406 [inline]
 do_syslog+0x2e62/0x3160 kernel/printk/printk.c:1531
 kmsg_read+0x142/0x1a0 fs/proc/kmsg.c:40
 proc_reg_read+0x25f/0x360 fs/proc/inode.c:223
 __vfs_read+0x1a9/0xc90 fs/read_write.c:425
 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+0xbc/0xf0 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x7f1ef77771fd
Code: d1 20 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 5e fa ff ff 48 89 04 24 b8 00 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 a7 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007f1ef4d16e30 EFLAGS: 00000293 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00000000014004b0 RCX: 00007f1ef77771fd
RDX: 0000000000000fff RSI: 00007f1ef654b5a0 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00000000013eb260 R09: 0000000004000001
R10: 0000000000000001 R11: 0000000000000293 R12: 000000000065e420
R13: 00007f1ef4d179c0 R14: 00007f1ef7dbc040 R15: 0000000000000003

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:150 [inline]
 kmsan_internal_poison_shadow+0x53/0x100 mm/kmsan/kmsan.c:134
 kmsan_slab_alloc+0xaa/0x120 mm/kmsan/kmsan_hooks.c:103
 slab_alloc_node mm/slub.c:2790 [inline]
 slab_alloc mm/slub.c:2799 [inline]
 kmem_cache_alloc_trace+0x8c5/0xd20 mm/slub.c:2816
 kmalloc include/linux/slab.h:552 [inline]
 syslog_print kernel/printk/printk.c:1358 [inline]
 do_syslog+0x263b/0x3160 kernel/printk/printk.c:1531
 kmsg_read+0x142/0x1a0 fs/proc/kmsg.c:40
 proc_reg_read+0x25f/0x360 fs/proc/inode.c:223
 __vfs_read+0x1a9/0xc90 fs/read_write.c:425
 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+0xbc/0xf0 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Byte 113 of 115 is uninitialized
Memory access of size 115 starts at ffff888056963800
Data copied to user address 00007f1ef654b5a0
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