loop2: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in hfs_find_set_zero_bits+0x74d/0xb60 fs/hfs/bitmap.c:45
 hfs_find_set_zero_bits+0x74d/0xb60 fs/hfs/bitmap.c:45
 hfs_vbm_search_free+0x13c/0x5b0 fs/hfs/bitmap.c:151
 hfs_extend_file+0x6a5/0x1b00 fs/hfs/extent.c:408
 hfs_get_block+0x435/0x1150 fs/hfs/extent.c:353
 __block_write_begin_int+0xaab/0x3000 fs/buffer.c:2116
 block_write_begin fs/buffer.c:2227 [inline]
 cont_write_begin+0x10df/0x1ba0 fs/buffer.c:2566
 hfs_write_begin+0x85/0x130 fs/hfs/inode.c:52
 cont_expand_zero fs/buffer.c:2493 [inline]
 cont_write_begin+0x35a/0x1ba0 fs/buffer.c:2556
 hfs_write_begin+0x85/0x130 fs/hfs/inode.c:52
 hfs_file_truncate+0x1d6/0xe60 fs/hfs/extent.c:494
 hfs_inode_setattr+0x964/0xaa0 fs/hfs/inode.c:654
 notify_change+0x1990/0x1aa0 fs/attr.c:552
 do_truncate+0x224/0x2a0 fs/open.c:65
 vfs_truncate+0x921/0x9d0 fs/open.c:115
 do_sys_truncate+0x103/0x240 fs/open.c:138
 __do_compat_sys_truncate fs/open.c:156 [inline]
 __se_compat_sys_truncate fs/open.c:154 [inline]
 __ia32_compat_sys_truncate+0x77/0xc0 fs/open.c:154
 ia32_sys_call+0xa11/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:93
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4167 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 __kmalloc_cache_noprof+0x7f7/0xed0 mm/slub.c:4367
 kmalloc_noprof include/linux/slab.h:905 [inline]
 hfs_mdb_get+0x1cc8/0x2a90 fs/hfs/mdb.c:175
 hfs_fill_super+0x3d0/0xb80 fs/hfs/super.c:337
 get_tree_bdev_flags+0x6e3/0x920 fs/super.c:1636
 get_tree_bdev+0x38/0x50 fs/super.c:1659
 hfs_get_tree+0x35/0x40 fs/hfs/super.c:388
 vfs_get_tree+0xb0/0x5c0 fs/super.c:1759
 do_new_mount+0x73c/0x1620 fs/namespace.c:3881
 path_mount+0x6db/0x1e90 fs/namespace.c:4208
 do_mount fs/namespace.c:4221 [inline]
 __do_sys_mount fs/namespace.c:4432 [inline]
 __se_sys_mount+0x6eb/0x7d0 fs/namespace.c:4409
 __ia32_sys_mount+0xe2/0x150 fs/namespace.c:4409
 ia32_sys_call+0x2733/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:22
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 10755 Comm: syz.2.1044 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
=====================================================