loop4: detected capacity change from 0 to 1024 ===================================================== BUG: KMSAN: uninit-value in __hfsplus_ext_read_extent fs/hfsplus/extents.c:167 [inline] BUG: KMSAN: uninit-value in __hfsplus_ext_cache_extent+0x7cb/0x990 fs/hfsplus/extents.c:191 __hfsplus_ext_read_extent fs/hfsplus/extents.c:167 [inline] __hfsplus_ext_cache_extent+0x7cb/0x990 fs/hfsplus/extents.c:191 hfsplus_file_truncate+0x7a3/0xfc0 fs/hfsplus/extents.c:600 hfsplus_setattr+0x344/0x5c0 fs/hfsplus/inode.c:264 notify_change+0x1990/0x1aa0 fs/attr.c:552 do_truncate+0x28f/0x310 fs/open.c:68 do_ftruncate+0x698/0x730 fs/open.c:195 do_sys_ftruncate fs/open.c:210 [inline] __do_sys_ftruncate fs/open.c:215 [inline] __se_sys_ftruncate fs/open.c:213 [inline] __x64_sys_ftruncate+0x11b/0x250 fs/open.c:213 x64_sys_call+0xfe3/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:78 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4154 [inline] slab_alloc_node mm/slub.c:4197 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x95f/0x1310 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] hfsplus_find_init+0x90/0x1d0 fs/hfsplus/bfind.c:21 hfsplus_file_truncate+0x513/0xfc0 fs/hfsplus/extents.c:583 hfsplus_setattr+0x344/0x5c0 fs/hfsplus/inode.c:264 notify_change+0x1990/0x1aa0 fs/attr.c:552 do_truncate+0x28f/0x310 fs/open.c:68 do_ftruncate+0x698/0x730 fs/open.c:195 do_sys_ftruncate fs/open.c:210 [inline] __do_sys_ftruncate fs/open.c:215 [inline] __se_sys_ftruncate fs/open.c:213 [inline] __x64_sys_ftruncate+0x11b/0x250 fs/open.c:213 x64_sys_call+0xfe3/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:78 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 1 UID: 0 PID: 6602 Comm: syz.4.223 Not tainted 6.15.0-syzkaller-13526-g7a912d04415b #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 =====================================================