------------[ cut here ]------------ WARNING: CPU: 1 PID: 5084 at mm/maccess.c:226 copy_from_user_nofault+0x160/0x1c0 mm/maccess.c:226 Modules linked in: CPU: 1 PID: 5084 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:copy_from_user_nofault+0x160/0x1c0 mm/maccess.c:226 Code: 24 45 31 f6 31 ff 89 de e8 8d f6 d8 ff 85 db 48 c7 c0 f2 ff ff ff 49 0f 44 c6 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 10 f3 d8 ff <0f> 0b e9 1c ff ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c ea fe RSP: 0018:ffffc90000dd09a8 EFLAGS: 00010246 RAX: ffffffff819ed900 RBX: 0000000000000000 RCX: ffff88801e091dc0 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ff7c19 R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: ffff88801e093548 R13: dffffc0000000000 R14: ffffc90000dd0a08 R15: 0000000000000000 FS: 000055557ea40500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31023ffc CR3: 0000000055c87000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline] ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline] bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163 bpf_prog_f71667c8aa58b018+0x3a/0xbbc bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline] bpf_trace_run2+0x15b/0x2d0 kernel/trace/bpf_trace.c:1915 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:118 trace_kfree include/trace/events/kmem.h:118 [inline] kfree+0x25f/0x2a0 mm/slub.c:4554 security_cred_free+0xbc/0xf0 security/security.c:1719 put_cred_rcu+0xdd/0x3e0 kernel/cred.c:115 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0x962/0x15d0 kernel/rcu/tree.c:2763 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:unwind_next_frame+0xf68/0x1d90 arch/x86/kernel/unwind_orc.c:585 Code: 00 48 8b 44 24 50 42 0f b6 04 28 84 c0 0f 85 74 09 00 00 48 8b 44 24 10 0f b7 30 c1 ee 04 83 e6 0f 83 fe 04 0f 84 91 01 00 00 <83> fe 01 0f 84 43 01 00 00 85 f6 0f 85 38 03 00 00 48 8b 44 24 30 vkms_vblank_simulate: vblank timer overrun RSP: 0018:ffffc9000313ee28 EFLAGS: 00000297 RAX: ffffffff8e798d6a RBX: ffffc9000313eee8 RCX: ffffffff8ddbe401 RDX: ffffc9000313ff58 RSI: 0000000000000000 RDI: ffffffff8e798d66 RBP: ffffc9000313ef30 R08: 0000000000000004 R09: 000000000000001a R10: fffff52000627de9 R11: 1ffff92000627de7 R12: 1ffffffff1cf31ad R13: dffffc0000000000 R14: ffffc9000313ef38 R15: ffffc9000313ef1e arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 kmem_cache_zalloc include/linux/slab.h:728 [inline] lsm_inode_alloc security/security.c:595 [inline] security_inode_alloc+0x30/0x110 security/security.c:1033 inode_init_always+0x8f4/0xcb0 fs/inode.c:232 alloc_inode fs/inode.c:268 [inline] new_inode_pseudo+0x8e/0x210 fs/inode.c:1001 new_inode+0x25/0x1c0 fs/inode.c:1030 debugfs_get_inode fs/debugfs/inode.c:72 [inline] __debugfs_create_file+0x148/0x510 fs/debugfs/inode.c:409 nsim_bpf_init+0x12f/0x250 drivers/net/netdevsim/bpf.c:635 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:311 [inline] nsim_create+0x2f7/0x3e0 drivers/net/netdevsim/netdev.c:365 __nsim_dev_port_add+0x5c7/0x980 drivers/net/netdevsim/dev.c:1312 nsim_dev_port_add_all+0x37/0x100 drivers/net/netdevsim/dev.c:1372 nsim_dev_probe+0x754/0x9c0 drivers/net/netdevsim/dev.c:1513 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 nsim_bus_dev_new drivers/net/netdevsim/bus.c:435 [inline] new_device_store+0x3d8/0x740 drivers/net/netdevsim/bus.c:302 kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f7d0b3f21ff Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007ffe8d499a90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f7d0b3f21ff RDX: 0000000000000003 RSI: 00007ffe8d499ae0 RDI: 0000000000000005 RBP: 00007f7d0b4792ef R08: 0000000000000000 R09: 00007ffe8d4998e7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 00007ffe8d499ae0 R14: 00007f7d0c178620 R15: 0000000000000003 ---------------- Code disassembly (best guess): 0: 00 48 8b add %cl,-0x75(%rax) 3: 44 24 50 rex.R and $0x50,%al 6: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax b: 84 c0 test %al,%al d: 0f 85 74 09 00 00 jne 0x987 13: 48 8b 44 24 10 mov 0x10(%rsp),%rax 18: 0f b7 30 movzwl (%rax),%esi 1b: c1 ee 04 shr $0x4,%esi 1e: 83 e6 0f and $0xf,%esi 21: 83 fe 04 cmp $0x4,%esi 24: 0f 84 91 01 00 00 je 0x1bb * 2a: 83 fe 01 cmp $0x1,%esi <-- trapping instruction 2d: 0f 84 43 01 00 00 je 0x176 33: 85 f6 test %esi,%esi 35: 0f 85 38 03 00 00 jne 0x373 3b: 48 8b 44 24 30 mov 0x30(%rsp),%rax