syzbot

KMSAN: kernel-infoleak in copy_page_to_iterdevtmpfs: mounted
Freeing unused kernel image memory: 4336K
Kernel memory protection disabled.
Run /sbin/init as init process
modprobe (2049) used greatest stack depth: 57352 bytes left
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:140 [inline]
BUG: KMSAN: kernel-infoleak in copy_page_to_iter_iovec lib/iov_iter.c:212 [inline]
BUG: KMSAN: kernel-infoleak in copy_page_to_iter+0x77a/0x1ac0 lib/iov_iter.c:846
CPU: 0 PID: 2325 Comm: blkid Not tainted 4.19.0-rc3+ #47
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+0x14b/0x190 lib/dump_stack.c:113
 kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
 kmsan_internal_check_memory+0x17e/0x1f0 mm/kmsan/kmsan.c:1020
 kmsan_copy_to_user+0x79/0xc0 mm/kmsan/kmsan_hooks.c:482
 copyout lib/iov_iter.c:140 [inline]
 copy_page_to_iter_iovec lib/iov_iter.c:212 [inline]
 copy_page_to_iter+0x77a/0x1ac0 lib/iov_iter.c:846
 generic_file_buffered_read mm/filemap.c:2186 [inline]
 generic_file_read_iter+0x3469/0x4430 mm/filemap.c:2363
 blkdev_read_iter+0x20d/0x270 fs/block_dev.c:1936
 call_read_iter include/linux/fs.h:1801 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x7bb/0x9f0 fs/read_write.c:418
 vfs_read+0x36f/0x6a0 fs/read_write.c:452
 ksys_read fs/read_write.c:578 [inline]
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read+0x173/0x350 fs/read_write.c:586
 __x64_sys_read+0x4a/0x70 fs/read_write.c:586
 do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x7f8e84991310
Code: 73 01 c3 48 8b 0d 28 4b 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d e5 a2 2b 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 6e 8a 01 00 48 89 04 24
RSP: 002b:00007ffdb3faa568 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000003e7fff0000 RCX: 00007f8e84991310
RDX: 0000000000000040 RSI: 00000000015f5c58 RDI: 0000000000000003
RBP: 00000000015f5c30 R08: 0000000000000068 R09: 0101010101010101
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000015f5030
R13: 0000000000000040 R14: 00000000015f5080 R15: 00000000015f5c48

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_alloc_meta_for_pages+0x146/0x700 mm/kmsan/kmsan.c:694
 kmsan_alloc_page+0x75/0xd0 mm/kmsan/kmsan_hooks.c:250
 __alloc_pages_nodemask+0xf6b/0x5c80 mm/page_alloc.c:4410
 alloc_pages_current+0x6b1/0x970 mm/mempolicy.c:2093
 alloc_pages include/linux/gfp.h:511 [inline]
 __page_cache_alloc+0x95/0x320 mm/filemap.c:947
 __do_page_cache_readahead+0x448/0x950 mm/readahead.c:194
 force_page_cache_readahead mm/readahead.c:241 [inline]
 page_cache_sync_readahead+0x7b5/0x890 mm/readahead.c:522
 generic_file_buffered_read mm/filemap.c:2093 [inline]
 generic_file_read_iter+0x1183/0x4430 mm/filemap.c:2363
 blkdev_read_iter+0x20d/0x270 fs/block_dev.c:1936
 call_read_iter include/linux/fs.h:1801 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x7bb/0x9f0 fs/read_write.c:418
 vfs_read+0x36f/0x6a0 fs/read_write.c:452
 ksys_read fs/read_write.c:578 [inline]
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read+0x173/0x350 fs/read_write.c:586
 __x64_sys_read+0x4a/0x70 fs/read_write.c:586
 do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 0-63 of 64 are uninitialized
Memory access starts at ffff8801c0b2c000
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