================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x45a/0x4d0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff888058e1c82a by task swapper/1/0 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc5-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xcd/0x680 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 rose_timer_expiry+0x45a/0x4d0 net/rose/rose_timer.c:183 call_timer_fn+0x197/0x620 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers+0x6ef/0x960 kernel/time/timer.c:2372 __run_timer_base kernel/time/timer.c:2384 [inline] __run_timer_base kernel/time/timer.c:2376 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2393 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2403 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 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+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: eb 6b 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 f0 21 00 fb f4 0c fb 02 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c6 RAX: 0000000000d3bead RBX: 0000000000000001 RCX: ffffffff8b881c69 RDX: 0000000000000000 RSI: ffffffff8de3106c RDI: ffffffff8c158660 RBP: ffffed1003c55488 R08: 0000000000000001 R09: ffffed10170a6645 R10: ffff8880b853322b R11: 0000000000000001 R12: 0000000000000001 R13: ffff88801e2aa440 R14: ffffffff90a97350 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:749 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 Allocated by task 9409: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] create_io_worker+0xc9/0x5b0 io_uring/io-wq.c:885 io_wq_create_worker io_uring/io-wq.c:339 [inline] io_wq_enqueue+0x4cc/0x980 io_uring/io-wq.c:1029 io_queue_iowq+0x246/0x530 io_uring/io_uring.c:513 io_queue_async+0x1fc/0x300 io_uring/io_uring.c:1957 io_queue_sqe io_uring/io_uring.c:1976 [inline] io_req_task_submit+0x1c8/0x1f0 io_uring/io_uring.c:1380 io_handle_tw_list+0x483/0x500 io_uring/io_uring.c:1067 tctx_task_work_run+0xac/0x380 io_uring/io_uring.c:1132 tctx_task_work+0x7a/0xd0 io_uring/io_uring.c:1150 task_work_run+0x14d/0x240 kernel/task_work.c:227 get_signal+0x1d1/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9409: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4842 create_io_worker+0x434/0x5b0 io_uring/io-wq.c:906 io_wq_create_worker io_uring/io-wq.c:339 [inline] io_wq_enqueue+0x4cc/0x980 io_uring/io-wq.c:1029 io_queue_iowq+0x246/0x530 io_uring/io_uring.c:513 io_queue_async+0x1fc/0x300 io_uring/io_uring.c:1957 io_queue_sqe io_uring/io_uring.c:1976 [inline] io_req_task_submit+0x1c8/0x1f0 io_uring/io_uring.c:1380 io_handle_tw_list+0x483/0x500 io_uring/io_uring.c:1067 tctx_task_work_run+0xac/0x380 io_uring/io_uring.c:1132 tctx_task_work+0x7a/0xd0 io_uring/io_uring.c:1150 task_work_run+0x14d/0x240 kernel/task_work.c:227 get_signal+0x1d1/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888058e1c800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff888058e1c800, ffff888058e1ca00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888058e1d400 pfn:0x58e1c head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801b841c80 ffffea0001625310 ffffea0000c6fd10 raw: ffff888058e1d400 0000000000100002 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801b841c80 ffffea0001625310 ffffea0000c6fd10 head: ffff888058e1d400 0000000000100002 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001638701 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 965, tgid 965 (kworker/u8:5), ts 63390422794, free_ts 15870759330 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab mm/slub.c:2619 [inline] new_slab+0x23b/0x330 mm/slub.c:2673 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949 __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x2f2/0x510 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x14c/0x870 net/ipv6/route.c:3811 ip6_route_add.part.0+0x22/0x1d0 net/ipv6/route.c:3940 ip6_route_add+0x45/0x60 net/ipv6/route.c:3937 addrconf_prefix_route+0x2fd/0x510 net/ipv6/addrconf.c:2487 addrconf_add_linklocal+0x329/0x500 net/ipv6/addrconf.c:3312 addrconf_addr_gen+0x36d/0x3c0 net/ipv6/addrconf.c:3441 addrconf_dev_config net/ipv6/addrconf.c:3487 [inline] addrconf_init_auto_addrs+0x4b9/0x8f0 net/ipv6/addrconf.c:3571 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706 __free_pages mm/page_alloc.c:5071 [inline] free_contig_range+0x183/0x4b0 mm/page_alloc.c:6927 destroy_args+0x7f6/0xa60 mm/debug_vm_pgtable.c:1009 debug_vm_pgtable+0x13b8/0x2d00 mm/debug_vm_pgtable.c:1389 do_one_initcall+0x120/0x6e0 init/main.c:1274 do_initcall_level init/main.c:1336 [inline] do_initcalls init/main.c:1352 [inline] do_basic_setup init/main.c:1371 [inline] kernel_init_freeable+0x5c2/0x900 init/main.c:1584 kernel_init+0x1c/0x2b0 init/main.c:1474 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888058e1c700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888058e1c780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888058e1c800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888058e1c880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888058e1c900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: eb 6b jmp 0x6d 2: 02 c3 add %bl,%al 4: cc int3 5: cc int3 6: cc int3 7: cc int3 8: 0f 1f 00 nopl (%rax) b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: f3 0f 1e fa endbr64 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d d3 f0 21 00 verw 0x21f0d3(%rip) # 0x21f0fb 28: fb sti 29: f4 hlt * 2a: e9 0c fb 02 00 jmp 0x2fb3b <-- trapping instruction 2f: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 36: 00 00 00 39: 66 90 xchg %ax,%ax 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop