------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 10180 at lib/refcount.c:25 refcount_warn_saturate+0xdd/0x140 lib/refcount.c:25
Modules linked in:

CPU: 0 PID: 10180 Comm: syz-executor.0 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0xdd/0x140 lib/refcount.c:25
Code: ea 52 c6 08 01 e8 8a 3e 9e 04 0f 0b eb 9d 80 3d d9 52 c6 08 00 75 94 48 c7 c7 00 44 fe 88 c6 05 c9 52 c6 08 01 e8 6a 3e 9e 04 <0f> 0b e9 7a ff ff ff 80 3d b3 52 c6 08 00 0f 85 6d ff ff ff 48 c7
RSP: 0000:ffffc9000b247f10 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffffffff8f0ff0a0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff88fe8140 RDI: fffff52001648fd4
RBP: 0000000000000002 R08: 0000000000000001 R09: ffff8880b9e4bfc7
R10: ffffed10173c97f8 R11: 746e756f63666572 R12: ffffc9000b247f58
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fd7fb57d700(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa311984008 CR3: 0000000045b9d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __refcount_add include/linux/refcount.h:199 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 __do_sys_memfd_secret mm/secretmem.c:221 [inline]
 __se_sys_memfd_secret mm/secretmem.c:194 [inline]
 __x64_sys_memfd_secret+0xe1/0x140 mm/secretmem.c:194
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fd7fbe07a39
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd7fb57d188 EFLAGS: 00000246 ORIG_RAX: 00000000000001bf
RAX: ffffffffffffffda RBX: 00007fd7fbf0af60 RCX: 00007fd7fbe07a39
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd7fbe61e8f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff971c67ef R14: 00007fd7fb57d300 R15: 0000000000022000