================================================================== BUG: KFENCE: use-after-free write in rose_timer_expiry+0x22d/0x4b0 net/rose/rose_timer.c:183 Use-after-free write at 0xffff88823bfe802a (in kfence-#243): rose_timer_expiry+0x22d/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 flush_smp_call_function_queue+0x1ed/0x250 kernel/smp.c:620 do_idle+0x4a8/0x510 kernel/sched/idle.c:352 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 rest_init+0x2de/0x300 init/main.c:745 start_kernel+0x47d/0x500 init/main.c:1102 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 kfence-#243: 0xffff88823bfe8000-0xffff88823bfe80ef, size=240, cache=skbuff_head_cache allocated by task 7088 on cpu 1 at 563.409394s (9.971555s ago): __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1336 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 freed by task 7088 on cpu 1 at 563.409458s (10.015378s ago): nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.16.0-rc6-syzkaller-00281-gf4a40a4282f4 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:rose_timer_expiry+0x22d/0x4b0 net/rose/rose_timer.c:183 Code: 80 3c 28 00 74 08 4c 89 e7 e8 5f 34 c4 f7 4d 8b 24 24 49 83 c4 2a 4c 89 e0 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 2c 02 00 00 <66> 41 ff 0c 24 4c 89 ff be 6e 00 00 00 ba ff ff ff ff b9 ff ff ff RSP: 0018:ffffc90000007b68 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88806af336f8 RCX: ffffffff8de95280 RDX: 0000000000000100 RSI: ffffffff8f6670f0 RDI: 0000000000000002 RBP: 1ffff1100d5e66bd R08: ffffffff8de95280 R09: 0000000000000004 R10: 0000000000000004 R11: 0000000000000100 R12: ffff88823bfe802a R13: dffffc0000000000 R14: ffff88806af331c0 R15: ffff88806af33000 FS: 0000000000000000(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff88823bfe802a CR3: 000000008cc0e000 CR4: 00000000003526f0 Call Trace: call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:flush_smp_call_function_queue+0x1ed/0x250 kernel/smp.c:620 Code: 00 4d 85 f6 75 16 e8 d2 89 0b 00 eb 15 e8 cb 89 0b 00 e8 66 dc b1 09 4d 85 f6 74 ea e8 bc 89 0b 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00 RSP: 0018:ffffffff8de07ce0 EFLAGS: 00000293 RAX: ffffffff81b49cc4 RBX: 0000000000000000 RCX: ffffffff8de95280 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff8de07d90 R08: ffffffff8fa0b2f7 R09: 1ffffffff1f4165e R10: dffffc0000000000 R11: fffffbfff1f4165f R12: 1ffffffff1bc0f9c R13: 0000000000000000 R14: 0000000000000200 R15: dffffc0000000000 do_idle+0x4a8/0x510 kernel/sched/idle.c:352 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 rest_init+0x2de/0x300 init/main.c:745 start_kernel+0x47d/0x500 init/main.c:1102 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 ================================================================== ---------------- Code disassembly (best guess): 0: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) 4: 74 08 je 0xe 6: 4c 89 e7 mov %r12,%rdi 9: e8 5f 34 c4 f7 call 0xf7c4346d e: 4d 8b 24 24 mov (%r12),%r12 12: 49 83 c4 2a add $0x2a,%r12 16: 4c 89 e0 mov %r12,%rax 19: 48 c1 e8 03 shr $0x3,%rax 1d: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 22: 84 c0 test %al,%al 24: 0f 85 2c 02 00 00 jne 0x256 * 2a: 66 41 ff 0c 24 decw (%r12) <-- trapping instruction 2f: 4c 89 ff mov %r15,%rdi 32: be 6e 00 00 00 mov $0x6e,%esi 37: ba ff ff ff ff mov $0xffffffff,%edx 3c: b9 .byte 0xb9 3d: ff (bad) 3e: ff (bad) 3f: ff .byte 0xff