=====================================================
BUG: KMSAN: uninit-value in bch2_extent_update_i_size_sectors+0x12c9/0x1660 fs/bcachefs/io_write.c:245
 bch2_extent_update_i_size_sectors+0x12c9/0x1660 fs/bcachefs/io_write.c:245
 bch2_extent_update+0x4f5/0xac0 fs/bcachefs/io_write.c:322
 bch2_extent_fallocate+0x1477/0x3320 fs/bcachefs/io_misc.c:111
 __bchfs_fallocate fs/bcachefs/fs-io.c:670 [inline]
 bchfs_fallocate fs/bcachefs/fs-io.c:733 [inline]
 bch2_fallocate_dispatch+0x3d76/0x55d0 fs/bcachefs/fs-io.c:780
 vfs_fallocate+0x7fa/0x8b0 fs/open.c:330
 ksys_fallocate fs/open.c:353 [inline]
 __do_sys_fallocate fs/open.c:361 [inline]
 __se_sys_fallocate fs/open.c:359 [inline]
 __x64_sys_fallocate+0x155/0x290 fs/open.c:359
 x64_sys_call+0x13f4/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:286
 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

Uninit was stored to memory at:
 memcpy_u64s_small fs/bcachefs/util.h:511 [inline]
 bkey_reassemble fs/bcachefs/bkey.h:505 [inline]
 bch2_extent_update_i_size_sectors+0x8f5/0x1660 fs/bcachefs/io_write.c:234
 bch2_extent_update+0x4f5/0xac0 fs/bcachefs/io_write.c:322
 bch2_extent_fallocate+0x1477/0x3320 fs/bcachefs/io_misc.c:111
 __bchfs_fallocate fs/bcachefs/fs-io.c:670 [inline]
 bchfs_fallocate fs/bcachefs/fs-io.c:733 [inline]
 bch2_fallocate_dispatch+0x3d76/0x55d0 fs/bcachefs/fs-io.c:780
 vfs_fallocate+0x7fa/0x8b0 fs/open.c:330
 ksys_fallocate fs/open.c:353 [inline]
 __do_sys_fallocate fs/open.c:361 [inline]
 __se_sys_fallocate fs/open.c:359 [inline]
 __x64_sys_fallocate+0x155/0x290 fs/open.c:359
 x64_sys_call+0x13f4/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:286
 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

Uninit was stored to memory at:
 memcpy_u64s_small fs/bcachefs/util.h:511 [inline]
 bkey_reassemble fs/bcachefs/bkey.h:505 [inline]
 btree_key_cache_fill fs/bcachefs/btree_key_cache.c:454 [inline]
 bch2_btree_path_traverse_cached_slowpath+0x5f02/0x79f0 fs/bcachefs/btree_key_cache.c:530
 bch2_btree_path_traverse_cached+0xd1a/0x1140
 bch2_btree_path_traverse_one+0x737/0x5290 fs/bcachefs/btree_iter.c:1155
 bch2_btree_path_traverse fs/bcachefs/btree_iter.h:225 [inline]
 bch2_btree_iter_peek_slot+0x128c/0x3840 fs/bcachefs/btree_iter.c:2473
 __bch2_bkey_get_iter fs/bcachefs/btree_iter.h:549 [inline]
 bch2_bkey_get_iter fs/bcachefs/btree_iter.h:563 [inline]
 bch2_extent_update_i_size_sectors+0x3cc/0x1660 fs/bcachefs/io_write.c:216
 bch2_extent_update+0x4f5/0xac0 fs/bcachefs/io_write.c:322
 bch2_extent_fallocate+0x1477/0x3320 fs/bcachefs/io_misc.c:111
 __bchfs_fallocate fs/bcachefs/fs-io.c:670 [inline]
 bchfs_fallocate fs/bcachefs/fs-io.c:733 [inline]
 bch2_fallocate_dispatch+0x3d76/0x55d0 fs/bcachefs/fs-io.c:780
 vfs_fallocate+0x7fa/0x8b0 fs/open.c:330
 ksys_fallocate fs/open.c:353 [inline]
 __do_sys_fallocate fs/open.c:361 [inline]
 __se_sys_fallocate fs/open.c:359 [inline]
 __x64_sys_fallocate+0x155/0x290 fs/open.c:359
 x64_sys_call+0x13f4/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:286
 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

Uninit was created at:
 __kmalloc_large_node+0x231/0x370 mm/slub.c:3994
 __do_kmalloc_node mm/slub.c:4027 [inline]
 __kmalloc_node+0xb10/0x10c0 mm/slub.c:4046
 kmalloc_node include/linux/slab.h:648 [inline]
 kvmalloc_node+0xc0/0x2d0 mm/util.c:634
 kvmalloc include/linux/slab.h:766 [inline]
 btree_bounce_alloc fs/bcachefs/btree_io.c:118 [inline]
 bch2_btree_node_read_done+0x4e68/0x75e0 fs/bcachefs/btree_io.c:1185
 btree_node_read_work+0x8a5/0x1eb0 fs/bcachefs/btree_io.c:1324
 bch2_btree_node_read+0x3d42/0x4b50
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1748 [inline]
 bch2_btree_root_read+0xa6c/0x13d0 fs/bcachefs/btree_io.c:1772
 read_btree_roots+0x454/0xee0 fs/bcachefs/recovery.c:457
 bch2_fs_recovery+0x7b6a/0x93e0 fs/bcachefs/recovery.c:785
 bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1043
 bch2_fs_open+0x152a/0x15f0 fs/bcachefs/super.c:2105
 bch2_mount+0x90d/0x1d90 fs/bcachefs/fs.c:1906
 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: 0 PID: 6078 Comm: syz-executor.3 Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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