[syzbot] [bcachefs?] KMSAN: uninit-value in bch2_inode_unpack (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ccb98ccef0e5 Merge tag 'platform-drivers-x86-v6.13-4' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13493818580000
kernel config: https://syzkaller.appspot.com/x/.config?x=31c2647cf06aa81e
dashboard link: https://syzkaller.appspot.com/bug?extid=9b79c816ed3895539cf4
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/da86466e08c0/disk-ccb98cce.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/673316cfa30c/vmlinux-ccb98cce.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4d50a89ed2d4/bzImage-ccb98cce.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9b79c8...@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in bch2_inode_unpack_v3 fs/bcachefs/inode.c:274 [inline]
BUG: KMSAN: uninit-value in bch2_inode_unpack+0x9fb/0x4ca0 fs/bcachefs/inode.c:331
bch2_inode_unpack_v3 fs/bcachefs/inode.c:274 [inline]
bch2_inode_unpack+0x9fb/0x4ca0 fs/bcachefs/inode.c:331
bch2_inode_rm+0xdbc/0x1260 fs/bcachefs/inode.c:1042
bch2_evict_inode+0x2d5/0x6a0 fs/bcachefs/fs.c:1836
evict+0x723/0xd10 fs/inode.c:796
iput_final fs/inode.c:1946 [inline]
iput+0x97b/0xdb0 fs/inode.c:1972
bch2_symlink+0x49f/0x540 fs/bcachefs/fs.c:821
vfs_symlink+0x1ed/0x460 fs/namei.c:4669
do_symlinkat+0x253/0x8b0 fs/namei.c:4695
__do_sys_symlink fs/namei.c:4716 [inline]
__se_sys_symlink fs/namei.c:4714 [inline]
__x64_sys_symlink+0xe0/0x140 fs/namei.c:4714
x64_sys_call+0x31ca/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:89
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

Uninit was stored to memory at:
memcpy_u64s_small fs/bcachefs/util.h:393 [inline]
bkey_reassemble fs/bcachefs/bkey.h:513 [inline]
btree_key_cache_create fs/bcachefs/btree_key_cache.c:259 [inline]
btree_key_cache_fill+0xd1a/0x3d60 fs/bcachefs/btree_key_cache.c:309
bch2_btree_path_traverse_cached+0x988/0xe20 fs/bcachefs/btree_key_cache.c:361
bch2_btree_path_traverse_one+0x749/0x47b0 fs/bcachefs/btree_iter.c:1159
bch2_btree_path_traverse fs/bcachefs/btree_iter.h:247 [inline]
bch2_btree_iter_peek_slot+0x10b7/0x3950 fs/bcachefs/btree_iter.c:2629
__bch2_bkey_get_iter fs/bcachefs/btree_iter.h:575 [inline]
bch2_bkey_get_iter fs/bcachefs/btree_iter.h:589 [inline]
bch2_inode_rm+0x95d/0x1260 fs/bcachefs/inode.c:1027
bch2_evict_inode+0x2d5/0x6a0 fs/bcachefs/fs.c:1836
evict+0x723/0xd10 fs/inode.c:796
iput_final fs/inode.c:1946 [inline]
iput+0x97b/0xdb0 fs/inode.c:1972
bch2_symlink+0x49f/0x540 fs/bcachefs/fs.c:821
vfs_symlink+0x1ed/0x460 fs/namei.c:4669
do_symlinkat+0x253/0x8b0 fs/namei.c:4695
__do_sys_symlink fs/namei.c:4716 [inline]
__se_sys_symlink fs/namei.c:4714 [inline]
__x64_sys_symlink+0xe0/0x140 fs/namei.c:4714
x64_sys_call+0x31ca/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:89
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

Uninit was created at:
___kmalloc_large_node+0x22c/0x370 mm/slub.c:4253
__kmalloc_large_node_noprof+0x3f/0x1e0 mm/slub.c:4270
__do_kmalloc_node mm/slub.c:4286 [inline]
__kmalloc_node_noprof+0xc96/0x1250 mm/slub.c:4304
__kvmalloc_node_noprof+0xc0/0x2d0 mm/util.c:650
btree_bounce_alloc fs/bcachefs/btree_io.c:124 [inline]
btree_node_sort+0x78a/0x1d30 fs/bcachefs/btree_io.c:323
bch2_btree_post_write_cleanup+0x1b0/0xf20 fs/bcachefs/btree_io.c:2248
bch2_btree_node_write+0x21c/0x2e0 fs/bcachefs/btree_io.c:2289
btree_node_write_if_need fs/bcachefs/btree_io.h:151 [inline]
__btree_node_flush+0x606/0x680 fs/bcachefs/btree_trans_commit.c:252
bch2_btree_node_flush0+0x35/0x60 fs/bcachefs/btree_trans_commit.c:261
journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:565
__bch2_journal_reclaim+0xda8/0x1670 fs/bcachefs/journal_reclaim.c:698
bch2_journal_reclaim_thread+0x18e/0x760 fs/bcachefs/journal_reclaim.c:740
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

CPU: 0 UID: 0 PID: 6027 Comm: syz.1.13 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
=====================================================


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