================================================================== BUG: KASAN: slab-use-after-free in rose_send_frame+0x29a/0x2c0 net/rose/rose_link.c:101 Read of size 8 at addr ffff8880580b4c20 by task syz.1.1784/12213 CPU: 1 UID: 0 PID: 12213 Comm: syz.1.1784 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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: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:finish_task_switch.isra.0+0x22a/0xc10 kernel/sched/core.c:5225 Code: fb 09 00 00 44 8b 05 09 8c 22 0f 45 85 c0 0f 85 be 01 00 00 4c 89 e7 e8 a4 f6 ff ff e8 4f 65 3a 00 fb 65 48 8b 1d ae c3 4d 12 <48> 8d bb 18 16 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffffc90003a3f810 EFLAGS: 00000206 RAX: 000000000004ea6f RBX: ffff888067830000 RCX: ffffffff81c380af RDX: 0000000000000000 RSI: ffffffff8de52fc1 RDI: ffffffff8c163380 RBP: ffffc90003a3f858 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff90ab7697 R11: 0000000000000000 R12: ffff8880b853a300 R13: ffff88801ea92440 R14: ffff8880b843a300 R15: ffff8880b853b130 context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1198/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 snd_rawmidi_write+0x496/0xc10 sound/core/rawmidi.c:1616 do_loop_readv_writev fs/read_write.c:850 [inline] do_loop_readv_writev fs/read_write.c:835 [inline] vfs_writev+0x5df/0xde0 fs/read_write.c:1059 do_writev+0x28c/0x340 fs/read_write.c:1103 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f45c158eec9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f45c24e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f45c17e5fa0 RCX: 00007f45c158eec9 RDX: 0000000000000002 RSI: 0000200000000840 RDI: 0000000000000004 RBP: 00007f45c1611f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f45c17e6038 R14: 00007f45c17e5fa0 R15: 00007ffcd8e92c98 Allocated by task 9931: 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:388 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405 kmalloc_noprof include/linux/slab.h:905 [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/0x7d0 net/rose/af_rose.c:1381 sock_do_ioctl+0x118/0x280 net/socket.c:1238 sock_ioctl+0x227/0x6b0 net/socket.c:1359 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 12221: 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:243 [inline] __kasan_slab_free+0x60/0x70 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2422 [inline] slab_free mm/slub.c:4695 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4894 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: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 The buggy address belongs to the object at ffff8880580b4c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 32 bytes inside of freed 512-byte region [ffff8880580b4c00, ffff8880580b4e00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880580b6400 pfn:0x580b4 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 ffffea0001614310 ffffea000160f210 raw: ffff8880580b6400 0000000000100004 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801b841c80 ffffea0001614310 ffffea000160f210 head: ffff8880580b6400 0000000000100004 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001602d01 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 5844, tgid 5844 (syz-executor), ts 65141152580, free_ts 15939071105 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2492 [inline] allocate_slab mm/slub.c:2660 [inline] new_slab+0x247/0x330 mm/slub.c:2714 ___slab_alloc+0xcf2/0x1750 mm/slub.c:3901 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3992 __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] __do_kmalloc_node mm/slub.c:4375 [inline] __kmalloc_noprof+0x2f2/0x510 mm/slub.c:4388 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:2488 addrconf_add_linklocal+0x329/0x500 net/ipv6/addrconf.c:3313 addrconf_addr_gen+0x364/0x3b0 net/ipv6/addrconf.c:3442 addrconf_dev_config net/ipv6/addrconf.c:3489 [inline] addrconf_init_auto_addrs+0x2ba/0x810 net/ipv6/addrconf.c:3567 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:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 __free_pages mm/page_alloc.c:5260 [inline] free_contig_range+0x183/0x4b0 mm/page_alloc.c:7091 destroy_args+0x794/0xc10 mm/debug_vm_pgtable.c:958 debug_vm_pgtable+0x1a32/0x3640 mm/debug_vm_pgtable.c:1345 do_one_initcall+0x120/0x6e0 init/main.c:1269 do_initcall_level init/main.c:1331 [inline] do_initcalls init/main.c:1347 [inline] do_basic_setup init/main.c:1366 [inline] kernel_init_freeable+0x5c2/0x910 init/main.c:1579 kernel_init+0x1c/0x2b0 init/main.c:1469 ret_from_fork+0x56a/0x730 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: ffff8880580b4b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880580b4b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880580b4c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880580b4c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880580b4d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: fb sti 1: 09 00 or %eax,(%rax) 3: 00 44 8b 05 add %al,0x5(%rbx,%rcx,4) 7: 09 8c 22 0f 45 85 c0 or %ecx,-0x3f7abaf1(%rdx,%riz,1) e: 0f 85 be 01 00 00 jne 0x1d2 14: 4c 89 e7 mov %r12,%rdi 17: e8 a4 f6 ff ff call 0xfffff6c0 1c: e8 4f 65 3a 00 call 0x3a6570 21: fb sti 22: 65 48 8b 1d ae c3 4d mov %gs:0x124dc3ae(%rip),%rbx # 0x124dc3d8 29: 12 * 2a: 48 8d bb 18 16 00 00 lea 0x1618(%rbx),%rdi <-- trapping instruction 31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 38: fc ff df 3b: 48 89 fa mov %rdi,%rdx 3e: 48 rex.W 3f: c1 .byte 0xc1