================================================================== BUG: KASAN: slab-use-after-free in rose_send_frame+0x29a/0x2c0 net/rose/rose_link.c:101 Read of size 8 at addr ffff888041ac7c20 by task swapper/0/0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 rose_send_frame+0x29a/0x2c0 net/rose/rose_link.c:101 rose_transmit_restart_request+0x1b8/0x240 net/rose/rose_link.c:198 rose_t0timer_expiry+0x1d/0x150 net/rose/rose_link.c:83 call_timer_fn+0x19a/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:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: b7 6c 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 83 65 29 00 fb f4 3c 0a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6 RAX: 000000000551398f RBX: 0000000000000000 RCX: ffffffff8b60c2a9 RDX: 0000000000000000 RSI: ffffffff8da2c177 RDI: ffffffff8bf073c0 RBP: fffffbfff1c12f40 R08: 0000000000000001 R09: ffffed1017086655 R10: ffff8880b84332ab R11: 0000000000000001 R12: 0000000000000000 R13: ffffffff8e097a00 R14: ffffffff908216d0 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x38d/0x500 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 rest_init+0x16b/0x2b0 init/main.c:757 start_kernel+0x3f6/0x4e0 init/main.c:1111 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 Allocated by task 20303: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kmalloc_noprof include/linux/slab.h:957 [inline] rose_add_node net/rose/rose_route.c:85 [inline] rose_rt_ioctl+0x880/0x2580 net/rose/rose_route.c:748 rose_ioctl+0x64d/0x7c0 net/rose/af_rose.c:1381 sock_do_ioctl+0x118/0x280 net/socket.c:1254 sock_ioctl+0x227/0x6b0 net/socket.c:1375 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 22279: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2543 [inline] slab_free mm/slub.c:6642 [inline] kfree+0x2b8/0x6d0 mm/slub.c:6849 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x53f/0x630 net/rose/rose_timer.c:183 call_timer_fn+0x19a/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:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 The buggy address belongs to the object at ffff888041ac7c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 32 bytes inside of freed 512-byte region [ffff888041ac7c00, ffff888041ac7e00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x41ac4 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813ffa6c80 ffffea0001035900 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ffa6c80 ffffea0001035900 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea000106b101 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9021, tgid 9021 (syz-executor), ts 356524367559, free_ts 356485591966 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5178 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3059 [inline] allocate_slab mm/slub.c:3232 [inline] new_slab+0x24a/0x360 mm/slub.c:3286 ___slab_alloc+0xd79/0x1a50 mm/slub.c:4655 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778 __slab_alloc_node mm/slub.c:4854 [inline] slab_alloc_node mm/slub.c:5276 [inline] __do_kmalloc_node mm/slub.c:5649 [inline] __kmalloc_noprof+0x501/0x880 mm/slub.c:5662 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x14c/0x870 net/ipv6/route.c:3809 ip6_route_add.part.0+0x22/0x1d0 net/ipv6/route.c:3938 ip6_route_add+0x45/0x60 net/ipv6/route.c:3935 addrconf_add_mroute+0x1dd/0x350 net/ipv6/addrconf.c:2552 addrconf_add_dev+0x14e/0x1c0 net/ipv6/addrconf.c:2570 inet6_addr_add+0xfe/0x960 net/ipv6/addrconf.c:3032 inet6_rtm_newaddr+0x1619/0x1c70 net/ipv6/addrconf.c:5059 page last free pid 42 tgid 42 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901 discard_slab mm/slub.c:3330 [inline] __put_partials+0x130/0x170 mm/slub.c:3876 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] kmem_cache_alloc_node_noprof+0x28a/0x770 mm/slub.c:5340 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1383 [inline] mld_newpack.isra.0+0x18e/0xa20 net/ipv6/mcast.c:1775 add_grhead+0x299/0x340 net/ipv6/mcast.c:1886 add_grec+0x11b5/0x1720 net/ipv6/mcast.c:2025 mld_send_cr net/ipv6/mcast.c:2148 [inline] mld_ifc_work+0x41f/0xbf0 net/ipv6/mcast.c:2693 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888041ac7b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888041ac7b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888041ac7c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888041ac7c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888041ac7d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: b7 6c mov $0x6c,%bh 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 83 65 29 00 verw 0x296583(%rip) # 0x2965ab 28: fb sti 29: f4 hlt * 2a: e9 3c 0a 03 00 jmp 0x30a6b <-- 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