================================================================== BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 Read of size 2 at addr ffff8880602cdc2a by task syz.6.1157/11166 CPU: 0 PID: 11166 Comm: syz.6.1157 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648 expire_timers kernel/time/timer.c:1699 [inline] __run_timers+0x53e/0x800 kernel/time/timer.c:1970 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 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:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6799 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 85 ae 8d f7 e8 c0 9a ba f7 fb bf 01 00 00 00 65 b5 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0018:ffffc9000335fa40 EFLAGS: 00000286 RAX: 5c0a0f7d172c9500 RBX: 0000000000000000 RCX: 5c0a0f7d172c9500 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: 0000000000000001 RBP: ffffc9000335faf0 R08: ffffffff901d40f7 R09: 1ffffffff203a81e R10: dffffc0000000000 R11: fffffbfff203a81f R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff9200066bf48 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681 RIP: 0010:follow_pud_mask mm/gup.c:759 [inline] RIP: 0010:follow_p4d_mask mm/gup.c:814 [inline] RIP: 0010:follow_page_mask+0x147/0x12d0 mm/gup.c:873 Code: 00 00 49 be 98 0f 00 00 00 00 f0 ff 48 89 de 4c 21 f6 31 ff e8 fa e9 cc ff 48 89 d8 4c 21 f0 0f 85 34 09 00 00 43 80 3c 2c 00 <74> 08 48 89 ef e8 5f f1 11 00 48 b9 00 00 00 00 80 88 ff ff 48 b8 RSP: 0018:ffffc9000335fbb0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00000000187ae067 RCX: ffff888025728000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888077b75670 R08: ffff888025728007 R09: 1ffff11004ae5000 R10: dffffc0000000000 R11: ffffed1004ae5001 R12: 1ffff1100ef6eace R13: dffffc0000000000 R14: fff0000000000f98 R15: 0000000000001012 __get_user_pages+0x3eb/0x11e0 mm/gup.c:1195 populate_vma_page_range+0x213/0x290 mm/gup.c:1529 __mm_populate+0x275/0x3b0 mm/gup.c:1638 mm_populate include/linux/mm.h:2646 [inline] __do_sys_mlockall mm/mlock.c:799 [inline] __se_sys_mlockall+0x316/0x3b0 mm/mlock.c:775 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: 0033:0x7fd07104a819 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:00007fd06f262028 EFLAGS: 00000246 ORIG_RAX: 0000000000000097 RAX: ffffffffffffffda RBX: 00007fd0712c4180 RCX: 00007fd07104a819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 00007fd0710e0c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd0712c4218 R14: 00007fd0712c4180 R15: 00007fff4f9ea098 Allocated by task 6801: 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_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] rose_add_node+0x227/0xdb0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa2b/0xe70 net/rose/rose_route.c:738 rose_ioctl+0x2a7/0x7d0 net/rose/af_rose.c:1372 sock_do_ioctl+0xfb/0x320 net/socket.c:1147 sock_ioctl+0x4d2/0x710 net/socket.c:1266 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 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 The buggy address belongs to the object at ffff8880602cdc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of 512-byte region [ffff8880602cdc00, ffff8880602cde00) The buggy address belongs to the page: page:ffffea000180b300 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880602cdc00 pfn:0x602cc head:ffffea000180b300 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001878308 ffffea000186fe08 ffff888016c41c80 raw: ffff8880602cdc00 0000000000100002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4228, ts 55183021659, free_ts 13685450914 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] __kmalloc_node_track_caller+0x1fc/0x3a0 mm/slub.c:4963 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] nlmsg_new include/net/netlink.h:953 [inline] inet6_ifa_notify net/ipv6/addrconf.c:5516 [inline] __ipv6_ifa_notify+0x203/0xe60 net/ipv6/addrconf.c:6172 ipv6_ifa_notify net/ipv6/addrconf.c:6224 [inline] addrconf_dad_completed+0x184/0xc80 net/ipv6/addrconf.c:4236 addrconf_dad_work+0xc8c/0x1540 net/ipv6/addrconf.c:-1 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 free_contig_range+0x96/0xf0 mm/page_alloc.c:9428 destroy_args+0xf0/0xa00 mm/debug_vm_pgtable.c:1018 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336 do_one_initcall+0x272/0x730 init/main.c:1316 do_initcall_level+0x137/0x1f0 init/main.c:1389 do_initcalls+0x4b/0x90 init/main.c:1405 kernel_init_freeable+0x3e9/0x570 init/main.c:1629 kernel_init+0x19/0x1b0 init/main.c:1520 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff8880602cdb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880602cdb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880602cdc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880602cdc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880602cdd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 43 c6 44 37 04 f8 movb $0xf8,0x4(%r15,%r14,1) 8: 74 0b je 0x15 a: 0f 0b ud2 c: 48 f7 03 08 00 00 00 testq $0x8,(%rbx) 13: 74 7f je 0x94 15: bf 01 00 00 00 mov $0x1,%edi 1a: e8 85 ae 8d f7 call 0xf78daea4 1f: e8 c0 9a ba f7 call 0xf7ba9ae4 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 65 b5 ff ff call 0xffffb594 <-- trapping instruction 2f: 43 c6 44 37 08 00 movb $0x0,0x8(%r15,%r14,1) 35: 48 c7 44 24 40 00 00 movq $0x0,0x40(%rsp) 3c: 00 00 3e: 9c pushf 3f: 8f .byte 0x8f