syzbot

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BUG: KMSAN: uninit-value in btrfs_clean_tree_block+0x2c3/0x370 fs/btrfs/disk-io.c:1134
 btrfs_clean_tree_block+0x2c3/0x370 fs/btrfs/disk-io.c:1134
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4858 [inline]
 btrfs_alloc_tree_block+0x7c5/0x22a0 fs/btrfs/extent-tree.c:4935
 __btrfs_cow_block+0x817/0x2510 fs/btrfs/ctree.c:416
 btrfs_cow_block+0xa83/0xcd0 fs/btrfs/ctree.c:571
 commit_cowonly_roots+0x227/0x1270 fs/btrfs/transaction.c:1284
 btrfs_commit_transaction+0x263c/0x5be0 fs/btrfs/transaction.c:2348
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4580
 close_ctree+0x50e/0xe6a fs/btrfs/disk-io.c:4695
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:391
 generic_shutdown_super+0x2b8/0x760 fs/super.c:462
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2417
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:332
 deactivate_super+0x19b/0x1b0 fs/super.c:363
 cleanup_mnt+0x783/0x850 fs/namespace.c:1186
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1193
 task_work_run+0x154/0x290 kernel/task_work.c:164
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x345/0x3d0 kernel/entry/common.c:171
 exit_to_user_mode_prepare kernel/entry/common.c:203 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x79/0xc0 kernel/entry/common.c:296
 __do_fast_syscall_32+0xa5/0xf0 arch/x86/entry/common.c:181
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 __alloc_pages+0xbbf/0x1090 mm/page_alloc.c:5448
 alloc_pages+0xa08/0xd50
 folio_alloc+0x7b/0x180 mm/mempolicy.c:2282
 filemap_alloc_folio mm/filemap.c:996 [inline]
 __filemap_get_folio+0xf06/0x1b80 mm/filemap.c:1992
 pagecache_get_page+0xc8/0x5a0 mm/folio-compat.c:126
 find_or_create_page include/linux/pagemap.h:615 [inline]
 alloc_extent_buffer+0x882/0x32f0 fs/btrfs/extent_io.c:6186
 btrfs_find_create_tree_block+0xb2/0xd0 fs/btrfs/disk-io.c:1098
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4834 [inline]
 btrfs_alloc_tree_block+0x56a/0x22a0 fs/btrfs/extent-tree.c:4935
 __btrfs_cow_block+0x817/0x2510 fs/btrfs/ctree.c:416
 btrfs_cow_block+0xa83/0xcd0 fs/btrfs/ctree.c:571
 commit_cowonly_roots+0x227/0x1270 fs/btrfs/transaction.c:1284
 btrfs_commit_transaction+0x263c/0x5be0 fs/btrfs/transaction.c:2348
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4580
 close_ctree+0x50e/0xe6a fs/btrfs/disk-io.c:4695
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:391
 generic_shutdown_super+0x2b8/0x760 fs/super.c:462
 kill_anon_super+0x63/0xb0 fs/super.c:1056
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2417
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:332
 deactivate_super+0x19b/0x1b0 fs/super.c:363
 cleanup_mnt+0x783/0x850 fs/namespace.c:1186
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1193
 task_work_run+0x154/0x290 kernel/task_work.c:164
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x345/0x3d0 kernel/entry/common.c:171
 exit_to_user_mode_prepare kernel/entry/common.c:203 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x79/0xc0 kernel/entry/common.c:296
 __do_fast_syscall_32+0xa5/0xf0 arch/x86/entry/common.c:181
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

CPU: 1 PID: 3501 Comm: syz-executor.3 Not tainted 5.18.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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