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BUG: KMSAN: kernel-infoleak in copyout+0x16b/0x1f0 lib/iov_iter.c:144
CPU: 1 PID: 1828 Comm: syz-executor.0 Not tainted 5.1.0-rc7+ #5
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+0x130/0x2a0 mm/kmsan/kmsan.c:619
 kmsan_internal_check_memory+0x974/0xa80 mm/kmsan/kmsan.c:713
 kmsan_copy_to_user+0xa9/0xb0 mm/kmsan/kmsan_hooks.c:492
 copyout+0x16b/0x1f0 lib/iov_iter.c:144
 copy_page_to_iter_iovec lib/iov_iter.c:216 [inline]
 copy_page_to_iter+0x654/0x1910 lib/iov_iter.c:905
 generic_file_buffered_read mm/filemap.c:2206 [inline]
 generic_file_read_iter+0x2979/0x3e70 mm/filemap.c:2386
 blkdev_read_iter+0x20d/0x270 fs/block_dev.c:1986
 do_iter_readv_writev+0x9b3/0xbe0 include/linux/fs.h:1860
 do_iter_read+0x30b/0xe10 fs/read_write.c:920
 vfs_readv fs/read_write.c:984 [inline]
 do_preadv+0x3b8/0x5a0 fs/read_write.c:1068
 __do_sys_preadv fs/read_write.c:1118 [inline]
 __se_sys_preadv+0xc6/0xe0 fs/read_write.c:1113
 __x64_sys_preadv+0x62/0x80 fs/read_write.c:1113
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x458da9
Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff90283bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458da9
RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff90283c6d4
R13: 00000000004c5bfd R14: 00000000004da1d8 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags+0x7a/0x130 mm/kmsan/kmsan.c:205
 kmsan_internal_alloc_meta_for_pages+0x10f/0x500 mm/kmsan/kmsan_hooks.c:99
 kmsan_alloc_page+0x7a/0xf0 mm/kmsan/kmsan_hooks.c:243
 __alloc_pages_nodemask+0x143d/0x5e90 mm/page_alloc.c:4655
 alloc_pages_current+0x6a0/0x9b0 mm/mempolicy.c:2132
 alloc_pages include/linux/gfp.h:511 [inline]
 __page_cache_alloc+0x95/0x320 mm/filemap.c:948
 page_cache_alloc include/linux/pagemap.h:221 [inline]
 generic_file_buffered_read mm/filemap.c:2294 [inline]
 generic_file_read_iter+0x1e3e/0x3e70 mm/filemap.c:2386
 blkdev_read_iter+0x20d/0x270 fs/block_dev.c:1986
 do_iter_readv_writev+0x9b3/0xbe0 include/linux/fs.h:1860
 do_iter_read+0x30b/0xe10 fs/read_write.c:920
 vfs_readv fs/read_write.c:984 [inline]
 do_preadv+0x3b8/0x5a0 fs/read_write.c:1068
 __do_sys_preadv fs/read_write.c:1118 [inline]
 __se_sys_preadv+0xc6/0xe0 fs/read_write.c:1113
 __x64_sys_preadv+0x62/0x80 fs/read_write.c:1113
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 0-4095 of 4096 are uninitialized
Memory access of size 4096 starts at ffff8881a593e000
Data copied to user address 0000000020019400
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