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: 134d, last: 34m

Sample crash report:

=====================================================
BUG: KMSAN: uninit-value in btrfs_clean_tree_block+0x28d/0x330 fs/btrfs/disk-io.c:1007
CPU: 0 PID: 10859 Comm: syz-executor.4 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+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197
 btrfs_clean_tree_block+0x28d/0x330 fs/btrfs/disk-io.c:1007
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4684 [inline]
 btrfs_alloc_tree_block+0x999/0x1f40 fs/btrfs/extent-tree.c:4762
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:989 [inline]
 __btrfs_cow_block+0xb28/0x2490 fs/btrfs/ctree.c:1045
 btrfs_cow_block+0xa36/0xca0 fs/btrfs/ctree.c:1497
 commit_cowonly_roots+0x1cb/0x1620 fs/btrfs/transaction.c:1186
 btrfs_commit_transaction+0x2415/0x5780 fs/btrfs/transaction.c:2283
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4023
 close_ctree+0x46a/0xd8f fs/btrfs/disk-io.c:4087
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:321
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1108
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2263
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1118
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1125
 task_work_run+0x140/0x280 kernel/task_work.c:151
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
 exit_to_user_mode_prepare+0x3c9/0x490 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x35/0x50 kernel/entry/common.c:266
 __do_fast_syscall_32+0x12d/0x160 arch/x86/entry/common.c:80
 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
RIP: 0023:0xf7f3b549
Code: 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 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000ffa2127c EFLAGS: 00000292 ORIG_RAX: 0000000000000034
RAX: 0000000000000000 RBX: 00000000ffa2130c RCX: 0000000000000002
RDX: 000000000a1ee228 RSI: 000000000a1ee2b4 RDI: 00000000080d8fe2
RBP: 00000000ffa2130c 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/0x90 mm/kmsan/kmsan.c:121
 kmsan_alloc_page+0xd3/0x1f0 mm/kmsan/kmsan_shadow.c:274
 __alloc_pages_nodemask+0x827/0xf90 mm/page_alloc.c:4989
 alloc_pages_current+0x7b6/0xb60 mm/mempolicy.c:2271
 alloc_pages include/linux/gfp.h:547 [inline]
 __page_cache_alloc mm/filemap.c:977 [inline]
 pagecache_get_page+0x1127/0x2070 mm/filemap.c:1828
 find_or_create_page include/linux/pagemap.h:404 [inline]
 alloc_extent_buffer+0x7ae/0x27d0 fs/btrfs/extent_io.c:5209
 btrfs_find_create_tree_block+0x68/0x80 fs/btrfs/disk-io.c:972
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4665 [inline]
 btrfs_alloc_tree_block+0x50d/0x1f40 fs/btrfs/extent-tree.c:4762
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:989 [inline]
 __btrfs_cow_block+0xb28/0x2490 fs/btrfs/ctree.c:1045
 btrfs_cow_block+0xa36/0xca0 fs/btrfs/ctree.c:1497
 commit_cowonly_roots+0x1cb/0x1620 fs/btrfs/transaction.c:1186
 btrfs_commit_transaction+0x2415/0x5780 fs/btrfs/transaction.c:2283
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4023
 close_ctree+0x46a/0xd8f fs/btrfs/disk-io.c:4087
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:321
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1108
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2263
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1118
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1125
 task_work_run+0x140/0x280 kernel/task_work.c:151
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
 exit_to_user_mode_prepare+0x3c9/0x490 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x35/0x50 kernel/entry/common.c:266
 __do_fast_syscall_32+0x12d/0x160 arch/x86/entry/common.c:80
 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
=====================================================

Crashes (9233):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Maintainers
ci-upstream-kmsan-gce-386	2021/01/27 13:40	https://github.com/google/kmsan.git master	73d62e81	a0ebf917	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/27 13:30	https://github.com/google/kmsan.git master	73d62e81	a0ebf917	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/27 12:29	https://github.com/google/kmsan.git master	73d62e81	a0ebf917	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/27 11:25	https://github.com/google/kmsan.git master	73d62e81	a0ebf917	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/27 10:37	https://github.com/google/kmsan.git master	73d62e81	a0ebf917	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/27 09:36	https://github.com/google/kmsan.git master	73d62e81	a0ebf917	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/27 09:08	https://github.com/google/kmsan.git master	73d62e81	a0ebf917	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/27 05:06	https://github.com/google/kmsan.git master	73d62e81	55a7d4df	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/26 20:57	https://github.com/google/kmsan.git master	73d62e81	55a7d4df	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/26 20:20	https://github.com/google/kmsan.git master	73d62e81	55a7d4df	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/26 19:10	https://github.com/google/kmsan.git master	73d62e81	55a7d4df	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/26 18:49	https://github.com/google/kmsan.git master	73d62e81	55a7d4df	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/26 17:45	https://github.com/google/kmsan.git master	73d62e81	55a7d4df	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/26 16:35	https://github.com/google/kmsan.git master	73d62e81	55a7d4df	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/25 10:08	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 19:51	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 12:13	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 11:15	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 10:06	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 08:56	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 08:44	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 07:38	https://github.com/google/kmsan.git master	73d62e81	52e37319	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 05:47	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 04:22	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 02:57	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 02:28	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 01:23	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/23 00:11	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 23:47	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 22:37	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 21:30	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 20:24	https://github.com/google/kmsan.git master	73d62e81	4080af96	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 17:04	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 13:00	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 11:32	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 07:55	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 05:21	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/22 00:55	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/21 22:58	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/21 21:35	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/21 18:23	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/21 15:43	https://github.com/google/kmsan.git master	73d62e81	d4f4eca5	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2021/01/17 14:00	https://github.com/google/kmsan.git master	73d62e81	813be542	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2020/09/19 08:10	https://github.com/google/kmsan.git master	c5a13b33	53ce8104	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2020/09/15 08:08	https://github.com/google/kmsan.git master	3b3ea602	6989d6f6	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
ci-upstream-kmsan-gce-386	2020/09/15 07:53	https://github.com/google/kmsan.git master	3b3ea602	6989d6f6	.config	log	report	info	clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org