------------[ cut here ]------------ refcount_t: saturated; leaking memory. WARNING: CPU: 1 PID: 5992 at lib/refcount.c:19 refcount_warn_saturate+0x13a/0x1d0 lib/refcount.c:19 Modules linked in: CPU: 1 UID: 0 PID: 5992 Comm: syz.1.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:refcount_warn_saturate+0x13a/0x1d0 lib/refcount.c:19 Code: e0 12 45 89 e8 07 41 bb fd 90 0f 0b 90 90 eb b7 e8 bb 35 f7 fd c6 05 99 ef 72 08 01 90 48 c7 c7 20 12 45 89 e8 e7 40 bb fd 90 <0f> 0b 90 90 eb 97 e8 9b 35 f7 fd c6 05 7d ef 72 08 01 90 48 c7 c7 RSP: 0018:ffffc90003587588 EFLAGS: 00010246 RAX: 3820b733b9153400 RBX: 0000000000000000 RCX: ffff888026911e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: ffffc900035876b0 R08: ffff8880b8f24253 R09: 1ffff110171e484a R10: dffffc0000000000 R11: ffffed10171e484b R12: ffff888073d391c0 R13: 1ffff920006b0ec4 R14: ffff888073d391c0 R15: 0000000000000000 FS: 00007fc2caeb96c0(0000) GS:ffff88812a5c4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc31c1d54e8 CR3: 000000007a052000 CR4: 00000000003526f0 Call Trace: __refcount_add_not_zero include/linux/refcount.h:187 [inline] refcount_add_not_zero include/linux/refcount.h:212 [inline] __vma_enter_locked+0x593/0x5d0 mm/mmap_lock.c:67 __vma_start_write+0x23/0x140 mm/mmap_lock.c:99 vma_start_write include/linux/mmap_lock.h:213 [inline] vma_merge_existing_range mm/vma.c:900 [inline] vma_modify+0xf62/0x1a70 mm/vma.c:1611 vma_modify_flags_uffd+0x1ff/0x250 mm/vma.c:1704 userfaultfd_clear_vma mm/userfaultfd.c:1997 [inline] userfaultfd_release_all+0x34c/0x5d0 mm/userfaultfd.c:2116 userfaultfd_release+0xe7/0x1b0 fs/userfaultfd.c:887 __fput+0x44c/0xa70 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 get_signal+0x11ec/0x1340 kernel/signal.c:2807 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc2c9f8f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc2caeb8fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: fffffffffffffff4 RBX: 00007fc2ca1e6090 RCX: 00007fc2c9f8f749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fc2ca013f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc2ca1e6128 R14: 00007fc2ca1e6090 R15: 00007fff5b64a828