[syzbot] [bcachefs?] KMSAN: uninit-value in bch2_checksum_update

[syzbot <syzbot+8d0e17030490d2299222@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    45db3ab70092 Merge tag '6.9-rc7-ksmbd-fixes' of git://git...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12bc7d04980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=617171361dd3cd47
dashboard link: https://syzkaller.appspot.com/bug?extid=8d0e17030490d2299222
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14b58970980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/232e7c2a73a5/disk-45db3ab7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7e9bf7c936ab/vmlinux-45db3ab7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5e8f98ee02d8/bzImage-45db3ab7.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/3f122e1fb69e/mount_2.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8d0e17030490d2299222@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in crc64_be+0x202/0x310 lib/crc64.c:59
 crc64_be+0x202/0x310 lib/crc64.c:59
 bch2_checksum_update+0x15e/0x1d0 fs/bcachefs/checksum.c:87
 bch2_checksum+0x3c5/0x7c0 fs/bcachefs/checksum.c:216
 __bch2_btree_node_write+0x528c/0x67c0 fs/bcachefs/btree_io.c:2151
 bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
 btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
 btree_update_nodes_written fs/bcachefs/btree_update_interior.c:829 [inline]
 btree_interior_update_work+0x3e09/0x47f0 fs/bcachefs/btree_update_interior.c:857
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0xa81/0x1bd0 kernel/workqueue.c:3348
 worker_thread+0xea5/0x1560 kernel/workqueue.c:3429
 kthread+0x3e2/0x540 kernel/kthread.c:388
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 memcpy_u64s_small fs/bcachefs/util.h:511 [inline]
 bkey_p_copy fs/bcachefs/bkey.h:46 [inline]
 bch2_sort_keys+0x1b4d/0x2cb0 fs/bcachefs/bkey_sort.c:194
 __bch2_btree_node_write+0x3acd/0x67c0 fs/bcachefs/btree_io.c:2100
 bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2288
 btree_node_write_if_need fs/bcachefs/btree_io.h:153 [inline]
 btree_update_nodes_written fs/bcachefs/btree_update_interior.c:829 [inline]
 btree_interior_update_work+0x3e09/0x47f0 fs/bcachefs/btree_update_interior.c:857
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0xa81/0x1bd0 kernel/workqueue.c:3348
 worker_thread+0xea5/0x1560 kernel/workqueue.c:3429
 kthread+0x3e2/0x540 kernel/kthread.c:388
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 __kmalloc_large_node+0x231/0x370 mm/slub.c:3927
 __do_kmalloc_node mm/slub.c:3960 [inline]
 __kmalloc_node+0xb10/0x10c0 mm/slub.c:3979
 kmalloc_node include/linux/slab.h:648 [inline]
 kvmalloc_node+0xc0/0x2d0 mm/util.c:634
 kvmalloc include/linux/slab.h:766 [inline]
 btree_node_data_alloc fs/bcachefs/btree_cache.c:98 [inline]
 __bch2_btree_node_mem_alloc+0x2cf/0x9d0 fs/bcachefs/btree_cache.c:143
 bch2_fs_btree_cache_init+0x4d1/0x960 fs/bcachefs/btree_cache.c:479
 bch2_fs_alloc+0x33ca/0x4210 fs/bcachefs/super.c:923
 bch2_fs_open+0xd9b/0x15f0 fs/bcachefs/super.c:2084
 bch2_mount+0x90d/0x1d90 fs/bcachefs/fs.c:1903
 legacy_get_tree+0x114/0x290 fs/fs_context.c:662
 vfs_get_tree+0xa7/0x570 fs/super.c:1779
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3352
 path_mount+0x742/0x1f20 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x725/0x810 fs/namespace.c:3875
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:3875
 x64_sys_call+0x2bf4/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 PID: 3712 Comm: kworker/u8:21 Not tainted 6.9.0-rc7-syzkaller-00056-g45db3ab70092 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: btree_update btree_interior_update_work
=====================================================


---
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