Kernel bug: KMSAN: uninit-value in bch2_bucket_alloc_early
Subsystem: bcachefs
Status: fixed

Crash report:
while marking u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 1db8f60c84bb244c written 8 min_key POS_MIN durability: 1 ptr: 0:42:0 gen 0, fixing
 done
bcachefs (loop0): going read-write
bcachefs (loop0): journal_replay...
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BUG: KMSAN: uninit-value in bch2_alloc_to_v4 fs/bcachefs/alloc_background.h:233 [inline]
BUG: KMSAN: uninit-value in bch2_bucket_alloc_early+0xe51/0x2810 fs/bcachefs/alloc_foreground.c:350
 bch2_alloc_to_v4 fs/bcachefs/alloc_background.h:233 [inline]
 bch2_bucket_alloc_early+0xe51/0x2810 fs/bcachefs/alloc_foreground.c:350
 bch2_bucket_alloc_trans+0x9ce/0x3180 fs/bcachefs/alloc_foreground.c:571
 bch2_bucket_alloc_set_trans+0x92c/0x1620 fs/bcachefs/alloc_foreground.c:726
 __open_bucket_add_buckets+0x1de7/0x3060 fs/bcachefs/alloc_foreground.c:969
 open_bucket_add_buckets+0x328/0x530 fs/bcachefs/alloc_foreground.c:1013
 bch2_alloc_sectors_start_trans+0x1730/0x32b0 fs/bcachefs/alloc_foreground.c:1336
 __bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:322 [inline]
 bch2_btree_reserve_get+0x9d6/0x2290 fs/bcachefs/btree_update_interior.c:532
 bch2_btree_update_start+0x1af9/0x2d60 fs/bcachefs/btree_update_interior.c:1230
 bch2_btree_split_leaf+0x120/0xc90 fs/bcachefs/btree_update_interior.c:1851
 bch2_trans_commit_error+0x1c0/0x1d60 fs/bcachefs/btree_trans_commit.c:908
 __bch2_trans_commit+0x1d60/0xd310 fs/bcachefs/btree_trans_commit.c:1085
 bch2_trans_commit fs/bcachefs/btree_update.h:183 [inline]
 wb_flush_one_slowpath+0x1e8/0x220 fs/bcachefs/btree_write_buffer.c:127
 wb_flush_one fs/bcachefs/btree_write_buffer.c:181 [inline]
 bch2_btree_write_buffer_flush_locked+0x455f/0x7180 fs/bcachefs/btree_write_buffer.c:379
 btree_write_buffer_flush_seq+0x3034/0x3250 fs/bcachefs/btree_write_buffer.c:551
 bch2_btree_write_buffer_journal_flush+0x103/0x1f0 fs/bcachefs/btree_write_buffer.c:567
 journal_flush_pins+0xce6/0x1780 fs/bcachefs/journal_reclaim.c:574
 journal_flush_done+0xe1/0x3f0 fs/bcachefs/journal_reclaim.c:830
 bch2_journal_flush_pins+0x2a9/0x3b0 fs/bcachefs/journal_reclaim.c:863
 bch2_journal_flush_all_pins fs/bcachefs/journal_reclaim.h:76 [inline]
 bch2_journal_replay+0x4920/0x4d30 fs/bcachefs/recovery.c:443
 bch2_run_recovery_pass fs/bcachefs/recovery_passes.c:226 [inline]
 bch2_run_recovery_passes+0x5a2/0x1160 fs/bcachefs/recovery_passes.c:291
 bch2_fs_recovery+0x489c/0x6230 fs/bcachefs/recovery.c:937
 bch2_fs_start+0x7ca/0xc20 fs/bcachefs/super.c:1030
 bch2_fs_get_tree+0x143a/0x2330 fs/bcachefs/fs.c:2203
 vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3560
 path_mount+0x742/0x1f10 fs/namespace.c:3887
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount+0x71f/0x800 fs/namespace.c:4088
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4088
 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

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:645
 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+0x4f0/0xb60 fs/bcachefs/btree_cache.c:652
 bch2_fs_alloc fs/bcachefs/super.c:908 [inline]
 bch2_fs_open+0x4b24/0x59c0 fs/bcachefs/super.c:2053
 bch2_fs_get_tree+0x986/0x2330 fs/bcachefs/fs.c:2190
 vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3560
 path_mount+0x742/0x1f10 fs/namespace.c:3887
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount+0x71f/0x800 fs/namespace.c:4088
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4088
 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: 0 UID: 0 PID: 5785 Comm: syz-executor830 Not tainted 6.13.0-syzkaller-07078-gb46c89c08f41 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
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