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BUG: KMSAN: uninit-value in strlen+0x5e/0xa0 lib/string.c:552
CPU: 0 PID: 6095 Comm: syz-executor.2 Not tainted 5.6.0-rc7-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+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 strlen+0x5e/0xa0 lib/string.c:552
 simple_attr_read+0x1ec/0x740 fs/libfs.c:935
 debugfs_attr_read+0x13e/0x290 fs/debugfs/file.c:360
 do_loop_readv_writev fs/read_write.c:714 [inline]
 do_iter_read+0x8df/0xe10 fs/read_write.c:935
 vfs_readv+0x1ee/0x280 fs/read_write.c:1053
 kernel_readv fs/splice.c:365 [inline]
 default_file_splice_read+0xb1d/0x11d0 fs/splice.c:422
 do_splice_to fs/splice.c:892 [inline]
 splice_direct_to_actor+0x5d8/0x11e0 fs/splice.c:971
 do_splice_direct+0x342/0x580 fs/splice.c:1080
 do_sendfile+0xff5/0x1d10 fs/read_write.c:1520
 __do_sys_sendfile64 fs/read_write.c:1581 [inline]
 __se_sys_sendfile64+0x2bb/0x360 fs/read_write.c:1567
 __x64_sys_sendfile64+0x56/0x70 fs/read_write.c:1567
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c829
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f947c1c0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000004fc2e0 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000007
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008dc R14: 00000000004cb816 R15: 00007f947c1c16d4

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2801 [inline]
 slab_alloc mm/slub.c:2810 [inline]
 kmem_cache_alloc_trace+0x6f3/0xd70 mm/slub.c:2827
 kmalloc include/linux/slab.h:555 [inline]
 simple_attr_open+0xd4/0x400 fs/libfs.c:894
 lowpan_enable_fops_open+0x94/0xb0 net/bluetooth/6lowpan.c:1105
 open_proxy_open+0x657/0x800 fs/debugfs/file.c:189
 do_dentry_open+0xf89/0x1820 fs/open.c:797
 vfs_open+0xaf/0xe0 fs/open.c:911
 do_last fs/namei.c:3490 [inline]
 path_openat+0x4d47/0x6bc0 fs/namei.c:3607
 do_filp_open+0x2b8/0x710 fs/namei.c:3637
 do_sys_openat2+0x92e/0xd40 fs/open.c:1146
 do_sys_open fs/open.c:1162 [inline]
 __do_sys_openat fs/open.c:1176 [inline]
 __se_sys_openat+0x24a/0x2b0 fs/open.c:1171
 __x64_sys_openat+0x56/0x70 fs/open.c:1171
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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