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BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:249
CPU: 1 PID: 11712 Comm: systemd-udevd Not tainted 5.10.0-rc4-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+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 kmsan_internal_check_memory+0x484/0x520 mm/kmsan/kmsan.c:437
 kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:249
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 copyout lib/iov_iter.c:147 [inline]
 copy_page_to_iter_iovec lib/iov_iter.c:222 [inline]
 copy_page_to_iter+0xace/0x2240 lib/iov_iter.c:929
 generic_file_buffered_read+0x4548/0x6640 mm/filemap.c:2332
 generic_file_read_iter+0x1c2/0xcf0 mm/filemap.c:2535
 blkdev_read_iter+0x1fe/0x2c0 fs/block_dev.c:1925
 call_read_iter include/linux/fs.h:1897 [inline]
 new_sync_read fs/read_write.c:415 [inline]
 vfs_read+0x13c1/0x1590 fs/read_write.c:496
 ksys_read+0x2af/0x4d0 fs/read_write.c:634
 __do_sys_read fs/read_write.c:644 [inline]
 __se_sys_read+0x92/0xb0 fs/read_write.c:642
 __x64_sys_read+0x4a/0x70 fs/read_write.c:642
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f966d4c3210
Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 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 4e fc ff ff 48 89 04 24
RSP: 002b:00007ffdcbc61868 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000560247154a90 RCX: 00007f966d4c3210
RDX: 0000000000040000 RSI: 0000560247154ab8 RDI: 000000000000000f
RBP: 00005602470f7fc0 R08: 00007f966d4ae318 R09: 0000000000040030
R10: 0000560247154aa8 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000040000 R14: 00005602470f8010 R15: 0000000000040000

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:121
 kmsan_alloc_page+0xd3/0x1f0 mm/kmsan/kmsan_shadow.c:274
 __alloc_pages_nodemask+0x84e/0xfb0 mm/page_alloc.c:4989
 alloc_pages_current+0x79b/0xb40 mm/mempolicy.c:2271
 alloc_pages include/linux/gfp.h:547 [inline]
 __page_cache_alloc mm/filemap.c:977 [inline]
 pagecache_get_page+0x1122/0x2050 mm/filemap.c:1828
 find_or_create_page include/linux/pagemap.h:404 [inline]
 grow_dev_page+0x1aa/0xde0 fs/buffer.c:974
 grow_buffers fs/buffer.c:1043 [inline]
 __getblk_slow fs/buffer.c:1070 [inline]
 __getblk_gfp+0x464/0x6a0 fs/buffer.c:1354
 sb_getblk include/linux/buffer_head.h:325 [inline]
 ext4_getblk+0x42e/0xc70 fs/ext4/inode.c:845
 ext4_xattr_inode_write fs/ext4/xattr.c:1362 [inline]
 ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1522 [inline]
 ext4_xattr_set_entry+0x62f5/0x75f0 fs/ext4/xattr.c:1646
 ext4_xattr_ibody_set fs/ext4/xattr.c:2222 [inline]
 ext4_xattr_set_handle+0x2310/0x3a30 fs/ext4/xattr.c:2378
 ext4_xattr_set+0x49c/0x6d0 fs/ext4/xattr.c:2491
 ext4_xattr_trusted_set+0xf3/0x110 fs/ext4/xattr_trusted.c:37
 __vfs_setxattr+0x94f/0x9a0 fs/xattr.c:177
 __vfs_setxattr_noperm+0x378/0xc90 fs/xattr.c:208
 __vfs_setxattr_locked+0x5f2/0x6a0 fs/xattr.c:266
 vfs_setxattr+0x1e4/0x4d0 fs/xattr.c:283
 setxattr+0x43d/0x8f0 fs/xattr.c:548
 path_setxattr+0x2cd/0x4f0 fs/xattr.c:567
 __do_sys_setxattr fs/xattr.c:582 [inline]
 __se_sys_setxattr+0xee/0x110 fs/xattr.c:578
 __ia32_sys_setxattr+0x62/0x80 fs/xattr.c:578
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Bytes 4-4095 of 4096 are uninitialized
Memory access of size 4096 starts at ffff88803783c000
Data copied to user address 0000560247171ab8
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