[syzbot] [bcachefs?] KMSAN: uninit-value in bch2_bkey_cmp_packed_inlined (2)

[syzbot <syzbot+65b594f491e4023728b0@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    7eef7e306d3c Merge tag 'for-6.13/dm-changes' of git://git...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=131543c0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c5486b9d7cc64830
dashboard link: https://syzkaller.appspot.com/bug?extid=65b594f491e4023728b0
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=12eb2f5f980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2331c33a914b/disk-7eef7e30.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8e50ed828391/vmlinux-7eef7e30.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a942e199e781/bzImage-7eef7e30.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/94dbb977c302/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+65b594f491e4023728b0@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in bch2_bkey_cmp_packed_inlined+0x8d0/0xd50 fs/bcachefs/bkey_cmp.h:115
 bch2_bkey_cmp_packed_inlined+0x8d0/0xd50 fs/bcachefs/bkey_cmp.h:115
 bch2_sort_keys_keep_unwritten_whiteouts+0xf94/0x19d0 fs/bcachefs/bkey_sort.c:184
 __bch2_btree_node_write+0x3ae8/0x6830 fs/bcachefs/btree_io.c:2095
 bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
 btree_node_write_if_need fs/bcachefs/btree_io.h:151 [inline]
 btree_update_nodes_written fs/bcachefs/btree_update_interior.c:833 [inline]
 btree_interior_update_work+0x3c24/0x4870 fs/bcachefs/btree_update_interior.c:861
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3310
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3391
 kthread+0x3e2/0x540 kernel/kthread.c:389
 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+0x22c/0x370 mm/slub.c:4238
 __kmalloc_large_node_noprof+0x3f/0x1e0 mm/slub.c:4255
 __do_kmalloc_node mm/slub.c:4271 [inline]
 __kmalloc_node_noprof+0xc96/0x1250 mm/slub.c:4289
 __kvmalloc_node_noprof+0xc0/0x2d0 mm/util.c:650
 btree_node_data_alloc fs/bcachefs/btree_cache.c:153 [inline]
 __bch2_btree_node_mem_alloc+0x2be/0xa80 fs/bcachefs/btree_cache.c:198
 bch2_fs_btree_cache_init+0x4e4/0xb50 fs/bcachefs/btree_cache.c:653
 bch2_fs_alloc fs/bcachefs/super.c:917 [inline]
 bch2_fs_open+0x4d3a/0x5b40 fs/bcachefs/super.c:2065
 bch2_fs_get_tree+0x983/0x22d0 fs/bcachefs/fs.c:2157
 vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3507
 path_mount+0x742/0x1f10 fs/namespace.c:3834
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x722/0x810 fs/namespace.c:4034
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4034
 x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.12.0-syzkaller-09567-g7eef7e306d3c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: btree_update btree_interior_update_work
=====================================================


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