loop4: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in hfs_find_set_zero_bits+0x836/0xca0 fs/hfs/bitmap.c:45
 hfs_find_set_zero_bits+0x836/0xca0 fs/hfs/bitmap.c:45
 hfs_vbm_search_free+0x141/0x530 fs/hfs/bitmap.c:151
 hfs_extend_file+0x69e/0x19f0 fs/hfs/extent.c:408
 hfs_get_block+0x3d8/0xf50 fs/hfs/extent.c:353
 __block_write_begin_int+0xa6b/0x2f80 fs/buffer.c:2122
 block_write_begin fs/buffer.c:2232 [inline]
 cont_write_begin+0xf82/0x1940 fs/buffer.c:2583
 hfs_write_begin+0x85/0x120 fs/hfs/inode.c:52
 generic_perform_write+0x4d8/0x1080 mm/filemap.c:4056
 __generic_file_write_iter+0x207/0x460 mm/filemap.c:4157
 generic_file_write_iter+0x102/0x5b0 mm/filemap.c:4183
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0xb2b/0x1540 fs/read_write.c:679
 ksys_write+0x240/0x4b0 fs/read_write.c:731
 __do_sys_write fs/read_write.c:742 [inline]
 __se_sys_write fs/read_write.c:739 [inline]
 __ia32_sys_write+0x91/0xe0 fs/read_write.c:739
 ia32_sys_call+0x2f4b/0x4180 arch/x86/include/generated/asm/syscalls_32.h:5
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4091 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 __kmalloc_cache_noprof+0x4f0/0xb00 mm/slub.c:4290
 kmalloc_noprof include/linux/slab.h:879 [inline]
 hfs_mdb_get+0x1bd4/0x28b0 fs/hfs/mdb.c:175
 hfs_fill_super+0x424/0xad0 fs/hfs/super.c:337
 get_tree_bdev_flags+0x6ec/0x910 fs/super.c:1636
 get_tree_bdev+0x37/0x50 fs/super.c:1659
 hfs_get_tree+0x34/0x40 fs/hfs/super.c:386
 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
 __ia32_sys_mount+0xe3/0x150 fs/namespace.c:4034
 ia32_sys_call+0x260e/0x4180 arch/x86/include/generated/asm/syscalls_32.h:22
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 7022 Comm: syz.4.308 Not tainted 6.12.0-syzkaller-01782-gbf9aa14fc523 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
=====================================================