loop6: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
BUG: KMSAN: uninit-value in __hfs_ext_cache_extent+0x69f/0x7e0 fs/hfs/extent.c:179
 __hfs_ext_read_extent fs/hfs/extent.c:160 [inline]
 __hfs_ext_cache_extent+0x69f/0x7e0 fs/hfs/extent.c:179
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x44c/0x19f0 fs/hfs/extent.c:401
 hfs_get_block+0x3d8/0xf50 fs/hfs/extent.c:353
 __block_write_begin_int+0xa73/0x2f80 fs/buffer.c:2116
 block_write_begin fs/buffer.c:2227 [inline]
 cont_write_begin+0xf84/0x1950 fs/buffer.c:2566
 hfs_write_begin+0x85/0x120 fs/hfs/inode.c:52
 cont_expand_zero fs/buffer.c:2493 [inline]
 cont_write_begin+0x32f/0x1950 fs/buffer.c:2556
 hfs_write_begin+0x85/0x120 fs/hfs/inode.c:52
 generic_perform_write+0x405/0x1060 mm/filemap.c:4102
 __generic_file_write_iter+0x207/0x460 mm/filemap.c:4219
 generic_file_write_iter+0x10c/0x930 mm/filemap.c:4245
 do_iter_readv_writev+0x93d/0xbc0 fs/read_write.c:-1
 vfs_writev+0x56a/0x14e0 fs/read_write.c:1055
 do_pwritev fs/read_write.c:1151 [inline]
 __do_compat_sys_pwritev2 fs/read_write.c:1296 [inline]
 __se_compat_sys_pwritev2+0x282/0x480 fs/read_write.c:1288
 __ia32_compat_sys_pwritev2+0x11d/0x1a0 fs/read_write.c:1288
 ia32_sys_call+0x2c11/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:380
 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:4157 [inline]
 slab_alloc_node mm/slub.c:4200 [inline]
 __do_kmalloc_node mm/slub.c:4330 [inline]
 __kmalloc_noprof+0x946/0x1260 mm/slub.c:4343
 kmalloc_noprof include/linux/slab.h:909 [inline]
 hfs_find_init+0x92/0x260 fs/hfs/bfind.c:21
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_extend_file+0x316/0x19f0 fs/hfs/extent.c:401
 hfs_get_block+0x3d8/0xf50 fs/hfs/extent.c:353
 __block_write_begin_int+0xa73/0x2f80 fs/buffer.c:2116
 block_write_begin fs/buffer.c:2227 [inline]
 cont_write_begin+0xf84/0x1950 fs/buffer.c:2566
 hfs_write_begin+0x85/0x120 fs/hfs/inode.c:52
 cont_expand_zero fs/buffer.c:2493 [inline]
 cont_write_begin+0x32f/0x1950 fs/buffer.c:2556
 hfs_write_begin+0x85/0x120 fs/hfs/inode.c:52
 generic_perform_write+0x405/0x1060 mm/filemap.c:4102
 __generic_file_write_iter+0x207/0x460 mm/filemap.c:4219
 generic_file_write_iter+0x10c/0x930 mm/filemap.c:4245
 do_iter_readv_writev+0x93d/0xbc0 fs/read_write.c:-1
 vfs_writev+0x56a/0x14e0 fs/read_write.c:1055
 do_pwritev fs/read_write.c:1151 [inline]
 __do_compat_sys_pwritev2 fs/read_write.c:1296 [inline]
 __se_compat_sys_pwritev2+0x282/0x480 fs/read_write.c:1288
 __ia32_compat_sys_pwritev2+0x11d/0x1a0 fs/read_write.c:1288
 ia32_sys_call+0x2c11/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:380
 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: 1 UID: 0 PID: 10063 Comm: syz.6.1345 Not tainted 6.15.0-rc1-syzkaller-00325-g7cdabafc0012 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
=====================================================