KMSAN: uninit-value in btrfs_clean_tree

KMSAN: uninit-value in btrfs_clean_tree_block
Status: upstream: reported on 2020/09/19 08:12
Reported-by: syzbot+37fb1c865f4d57cc1e7c@syzkaller.appspotmail.com
First crash: 378d, last: 53d

Sample crash report:

=====================================================
BUG: KMSAN: uninit-value in btrfs_clean_tree_block+0x2a9/0x350 fs/btrfs/disk-io.c:1143
CPU: 0 PID: 9640 Comm: syz-executor.3 Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/report.c:121
 __msan_warning+0xd7/0x160 mm/kmsan/instrumentation.c:201
 btrfs_clean_tree_block+0x2a9/0x350 fs/btrfs/disk-io.c:1143
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4756 [inline]
 btrfs_alloc_tree_block+0x7eb/0x2140 fs/btrfs/extent-tree.c:4834
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:402 [inline]
 __btrfs_cow_block+0xb93/0x2760 fs/btrfs/ctree.c:458
 btrfs_cow_block+0xa3c/0xc90 fs/btrfs/ctree.c:613
 commit_cowonly_roots+0x1c8/0x1560 fs/btrfs/transaction.c:1249
 btrfs_commit_transaction+0x212b/0x5a10 fs/btrfs/transaction.c:2328
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4314
 close_ctree+0x4da/0xf87 fs/btrfs/disk-io.c:4381
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:351
 generic_shutdown_super+0x2bb/0x650 fs/super.c:465
 kill_anon_super+0x63/0xb0 fs/super.c:1057
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2379
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x72b/0x800 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x48b/0x590 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:302
 __do_fast_syscall_32+0x158/0x1b0 arch/x86/entry/common.c:152
 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:179
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:222
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f2c549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000ffc6123c EFLAGS: 00000292 ORIG_RAX: 0000000000000034
RAX: 0000000000000000 RBX: 00000000ffc612e0 RCX: 0000000000000002
RDX: 000000000816c000 RSI: 0000000000000000 RDI: 00000000080ea118
RBP: 00000000ffc612e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x80 mm/kmsan/core.c:106
 kmsan_alloc_page+0x1af/0x270 mm/kmsan/shadow.c:283
 __alloc_pages+0xb14/0xf70 mm/page_alloc.c:5241
 alloc_pages+0x7b6/0xb60 mm/mempolicy.c:2272
 __page_cache_alloc mm/filemap.c:1005 [inline]
 pagecache_get_page+0x111d/0x2040 mm/filemap.c:1885
 find_or_create_page include/linux/pagemap.h:420 [inline]
 alloc_extent_buffer+0x8c1/0x3390 fs/btrfs/extent_io.c:5847
 btrfs_find_create_tree_block+0xb6/0xd0 fs/btrfs/disk-io.c:1107
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4732 [inline]
 btrfs_alloc_tree_block+0x545/0x2140 fs/btrfs/extent-tree.c:4834
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:402 [inline]
 __btrfs_cow_block+0xb93/0x2760 fs/btrfs/ctree.c:458
 btrfs_cow_block+0xa3c/0xc90 fs/btrfs/ctree.c:613
 commit_cowonly_roots+0x1c8/0x1560 fs/btrfs/transaction.c:1249
 btrfs_commit_transaction+0x212b/0x5a10 fs/btrfs/transaction.c:2328
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4314
 close_ctree+0x4da/0xf87 fs/btrfs/disk-io.c:4381
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:351
 generic_shutdown_super+0x2bb/0x650 fs/super.c:465
 kill_anon_super+0x63/0xb0 fs/super.c:1057
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2379
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x72b/0x800 fs/namespace.c:1136
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1143
 task_work_run+0x140/0x280 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x48b/0x590 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x35/0x60 kernel/entry/common.c:302
 __do_fast_syscall_32+0x158/0x1b0 arch/x86/entry/common.c:152
 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:179
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:222
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
=====================================================

Crashes (18531):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci-upstream-kmsan-gce-386	2021/08/06 12:40	https://github.com/google/kmsan.git master	ee9407ea37bf	f9e341e3	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/06 12:03	https://github.com/google/kmsan.git master	ee9407ea37bf	f9e341e3	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/06 11:01	https://github.com/google/kmsan.git master	ee9407ea37bf	f9e341e3	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/06 10:28	https://github.com/google/kmsan.git master	ee9407ea37bf	f9e341e3	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/06 09:26	https://github.com/google/kmsan.git master	ee9407ea37bf	f9e341e3	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/06 06:16	https://github.com/google/kmsan.git master	ee9407ea37bf	d2d6e680	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 21:26	https://github.com/google/kmsan.git master	ee9407ea37bf	d2d6e680	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 20:50	https://github.com/google/kmsan.git master	ee9407ea37bf	d2d6e680	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 19:47	https://github.com/google/kmsan.git master	ee9407ea37bf	d2d6e680	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 18:41	https://github.com/google/kmsan.git master	ee9407ea37bf	d2d6e680	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 09:49	https://github.com/google/kmsan.git master	925ba2a2a2fd	7f7bb950	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 09:30	https://github.com/google/kmsan.git master	925ba2a2a2fd	7f7bb950	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 08:23	https://github.com/google/kmsan.git master	925ba2a2a2fd	7f7bb950	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 07:36	https://github.com/google/kmsan.git master	925ba2a2a2fd	7f7bb950	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 06:35	https://github.com/google/kmsan.git master	925ba2a2a2fd	7f7bb950	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 05:49	https://github.com/google/kmsan.git master	925ba2a2a2fd	7f7bb950	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 03:22	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/05 01:05	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 23:25	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 20:14	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 20:08	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 19:06	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 18:33	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 17:29	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 17:03	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 16:02	https://github.com/google/kmsan.git master	b87ff0bc1209	b97d64c9	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 14:24	https://github.com/google/kmsan.git master	b87ff0bc1209	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 13:40	https://github.com/google/kmsan.git master	b87ff0bc1209	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 12:58	https://github.com/google/kmsan.git master	b87ff0bc1209	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 11:52	https://github.com/google/kmsan.git master	b87ff0bc1209	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 11:25	https://github.com/google/kmsan.git master	b87ff0bc1209	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 10:24	https://github.com/google/kmsan.git master	b87ff0bc1209	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 10:13	https://github.com/google/kmsan.git master	b87ff0bc1209	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/04 09:10	https://github.com/google/kmsan.git master	fc388325c43b	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/03 19:41	https://github.com/google/kmsan.git master	fc388325c43b	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/03 18:39	https://github.com/google/kmsan.git master	fc388325c43b	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/03 17:40	https://github.com/google/kmsan.git master	fc388325c43b	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/03 16:35	https://github.com/google/kmsan.git master	fc388325c43b	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/03 15:59	https://github.com/google/kmsan.git master	fc388325c43b	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/03 14:58	https://github.com/google/kmsan.git master	fc388325c43b	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/02 21:53	https://github.com/google/kmsan.git master	d41122e877c7	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/08/02 19:14	https://github.com/google/kmsan.git master	d41122e877c7	6c236867	.config	log	report	info	KMSAN: uninit-value in btrfs_clean_tree_block
ci-upstream-kmsan-gce-386	2021/01/17 14:00	https://github.com/google/kmsan.git master	73d62e81b476	813be542	.config	log	report	info
ci-upstream-kmsan-gce-386	2020/09/19 08:10	https://github.com/google/kmsan.git master	c5a13b33ec11	53ce8104	.config	log	report	info
ci-upstream-kmsan-gce-386	2020/09/15 08:08	https://github.com/google/kmsan.git master	3b3ea6028136	6989d6f6	.config	log	report	info
ci-upstream-kmsan-gce-386	2020/09/15 07:53	https://github.com/google/kmsan.git master	3b3ea6028136	6989d6f6	.config	log	report	info