------------[ cut here ]------------ !atomic_long_inc_not_zero(&event->refcount) WARNING: kernel/events/core.c:10739 at __perf_event_overflow+0xb9e/0xec0 kernel/events/core.c:10739, CPU#0: syz.3.2865/13046 Modules linked in: CPU: 0 UID: 0 PID: 13046 Comm: syz.3.2865 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__perf_event_overflow+0xb9e/0xec0 kernel/events/core.c:10739 Code: 0b 37 00 4d 89 3e 4c 8b 7c 24 10 e9 c2 fc ff ff e8 e7 e1 cc ff 49 bd 00 00 00 00 00 fc ff df e9 08 fe ff ff e8 d3 e1 cc ff 90 <0f> 0b 90 e9 21 ff ff ff e8 c5 e1 cc ff 48 c7 c7 00 1b d7 8b e8 e9 RSP: 0018:ffffc9000cbc72c0 EFLAGS: 00010293 RAX: ffffffff81f8aabd RBX: ffff88807d64cc60 RCX: ffff888025a95ac0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000cbc73d0 R08: ffff88807d64cdb7 R09: 1ffff1100fac99b6 R10: dffffc0000000000 R11: ffffed100fac99b7 R12: ffff88807d64cb60 R13: dffffc0000000000 R14: ffff88807d64cdb0 R15: 0000000000000000 FS: 00007f3f704486c0(0000) GS:ffff888125466000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007c346000 CR4: 00000000003526f0 Call Trace: perf_swevent_overflow kernel/events/core.c:10837 [inline] perf_swevent_event+0x323/0x650 kernel/events/core.c:-1 do_perf_sw_event kernel/events/core.c:10977 [inline] ___perf_sw_event+0x4a6/0x730 kernel/events/core.c:11004 __perf_sw_event+0xf9/0x1a0 kernel/events/core.c:11016 perf_sw_event include/linux/perf_event.h:1604 [inline] do_user_addr_fault+0x12a8/0x1340 arch/x86/mm/fault.c:1281 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0010:rep_movs_alternative+0x4a/0x90 arch/x86/lib/copy_user_64.S:74 Code: cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08 73 e8 eb c5 a4 c3 cc cc cc cc 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 RSP: 0018:ffffc9000cbc78d8 EFLAGS: 00050206 RAX: 00007ffffffff001 RBX: ffff888042bb0000 RCX: 000000000000fe33 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff888042bb0000 RBP: ffffc9000cbc7a30 R08: ffff888042bbfe32 R09: 1ffff11008577fc6 R10: dffffc0000000000 R11: ffffed1008577fc7 R12: ffffc9000cbc7bb8 R13: 0000000000000000 R14: 000000000000fe33 R15: 1ffff92001978f77 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] copy_from_user_iter lib/iov_iter.c:67 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:302 [inline] iterate_and_advance include/linux/iov_iter.h:330 [inline] __copy_from_iter lib/iov_iter.c:261 [inline] _copy_from_iter+0x21b/0x1670 lib/iov_iter.c:272 copy_from_iter include/linux/uio.h:228 [inline] copy_from_iter_full include/linux/uio.h:245 [inline] memcpy_from_msg include/linux/skbuff.h:4273 [inline] netlink_sendmsg+0x6c0/0xb40 net/netlink/af_netlink.c:1879 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] sock_write_iter+0x503/0x550 net/socket.c:1195 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3f6f59a539 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3f70448028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3f6f805fa0 RCX: 00007f3f6f59a539 RDX: 000000000000fe33 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f3f6f62dee0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3f6f806038 R14: 00007f3f6f805fa0 R15: 00007fff83dcc0c8 ---------------- Code disassembly (best guess): 0: cc int3 1: cc int3 2: cc int3 3: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) a: 00 00 00 d: 0f 1f 00 nopl (%rax) 10: 48 8b 06 mov (%rsi),%rax 13: 48 89 07 mov %rax,(%rdi) 16: 48 83 c6 08 add $0x8,%rsi 1a: 48 83 c7 08 add $0x8,%rdi 1e: 83 e9 08 sub $0x8,%ecx 21: 74 db je 0xfffffffe 23: 83 f9 08 cmp $0x8,%ecx 26: 73 e8 jae 0x10 28: eb c5 jmp 0xffffffef * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: c3 ret 2d: cc int3 2e: cc int3 2f: cc int3 30: cc int3 31: 48 8b 06 mov (%rsi),%rax 34: 48 89 07 mov %rax,(%rdi) 37: 48 8d 47 08 lea 0x8(%rdi),%rax 3b: 48 83 e0 f8 and $0xfffffffffffffff8,%rax 3f: 48 rex.W