================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88807bf7842a by task udevd/5199 CPU: 0 UID: 0 PID: 5199 Comm: udevd Not tainted 6.15.0-rc4-syzkaller-00995-g3e52667a9c32 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 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:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5870 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 6b f1 d7 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000300ef98 EFLAGS: 00000206 RAX: f98e9eae303b2a00 RBX: 0000000000000000 RCX: f98e9eae303b2a00 RDX: 0000000000000000 RSI: ffffffff8d93c212 RDI: ffffffff8bc1d020 RBP: ffffffff817199f5 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff817199f5 R12: 0000000000000002 R13: ffffffff8df3b860 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4341 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x1e8/0x5a0 security/tomoyo/file.c:723 tomoyo_path_mknod+0x142/0x190 security/tomoyo/tomoyo.c:252 security_path_mknod+0x17e/0x3a0 security/security.c:1899 may_o_create fs/namei.c:3520 [inline] lookup_open fs/namei.c:3664 [inline] open_last_lookups fs/namei.c:3800 [inline] path_openat+0xd56/0x3830 fs/namei.c:4036 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f426b4a7407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007fffc9fbeb80 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f426bc35880 RCX: 00007f426b4a7407 RDX: 0000000000080141 RSI: 0000557b8305102e RDI: ffffffffffffff9c RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001a4 R11: 0000000000000202 R12: 00000000ffffffff R13: 00000000ffffffff R14: ffffffffffffffff R15: 0000000000000000 Allocated by task 9528: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4372 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] mca_alloc net/ipv6/mcast.c:884 [inline] __ipv6_dev_mc_inc+0x420/0xaf0 net/ipv6/mcast.c:975 ipv6_add_dev+0xe63/0x1370 net/ipv6/addrconf.c:473 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3651 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2266 [inline] call_netdevice_notifiers net/core/dev.c:2280 [inline] register_netdevice+0x1608/0x1ae0 net/core/dev.c:11102 rtnl_newlink_create+0x31f/0xb00 net/core/rtnetlink.c:3836 __rtnl_newlink net/core/rtnetlink.c:3951 [inline] rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4066 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x219/0x490 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 __sys_sendto+0x3bd/0x520 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6099: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2398 [inline] slab_free_freelist_hook mm/slub.c:2427 [inline] slab_free_bulk mm/slub.c:4680 [inline] kmem_cache_free_bulk+0x2d1/0x520 mm/slub.c:5257 kfree_bulk include/linux/slab.h:794 [inline] kvfree_rcu_bulk+0xe5/0x1e0 mm/slab_common.c:1516 kvfree_rcu_drain_ready mm/slab_common.c:1699 [inline] kfree_rcu_monitor+0x211/0x2a0 mm/slab_common.c:1772 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:548 kvfree_call_rcu+0xbb/0x410 mm/slab_common.c:1962 __ipv6_dev_mc_dec+0x31f/0x390 net/ipv6/mcast.c:1024 ipv6_mc_destroy_dev+0x33c/0x5a0 net/ipv6/mcast.c:2852 addrconf_ifdown+0x139e/0x1880 net/ipv6/addrconf.c:3997 addrconf_notify+0x1bc/0x1010 net/ipv6/addrconf.c:-1 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2266 [inline] call_netdevice_notifiers net/core/dev.c:2280 [inline] unregister_netdevice_many_notify+0x15d4/0x2320 net/core/dev.c:12036 unregister_netdevice_many net/core/dev.c:12099 [inline] default_device_exit_batch+0x819/0x890 net/core/dev.c:12601 ops_exit_list net/core/net_namespace.c:206 [inline] ops_undo_list+0x522/0x990 net/core/net_namespace.c:253 cleanup_net+0x4c5/0x8a0 net/core/net_namespace.c:686 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88807bf78400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff88807bf78400, ffff88807bf78600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807bf7bc00 pfn:0x7bf78 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 ffff88801a041c80 ffffea0000a2cb10 ffffea0001ef3610 raw: ffff88807bf7bc00 0000000000100009 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801a041c80 ffffea0000a2cb10 ffffea0001ef3610 head: ffff88807bf7bc00 0000000000100009 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001efde01 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 5832, tgid 5832 (syz-executor), ts 91714343535, free_ts 91610379846 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1714 prep_new_page mm/page_alloc.c:1722 [inline] get_page_from_freelist+0x21e0/0x22c0 mm/page_alloc.c:3684 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4966 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2468 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2632 new_slab mm/slub.c:2686 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3872 __slab_alloc mm/slub.c:3962 [inline] __slab_alloc_node mm/slub.c:4037 [inline] slab_alloc_node mm/slub.c:4198 [inline] __do_kmalloc_node mm/slub.c:4340 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x147/0xa70 net/ipv6/route.c:3782 addrconf_f6i_alloc+0x1c7/0x420 net/ipv6/route.c:4703 fixup_permanent_addr net/ipv6/addrconf.c:3584 [inline] addrconf_permanent_addr+0x274/0x9d0 net/ipv6/addrconf.c:3623 addrconf_notify+0x887/0x1010 net/ipv6/addrconf.c:3695 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2266 [inline] call_netdevice_notifiers net/core/dev.c:2280 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9489 do_setlink+0xcb9/0x40d0 net/core/rtnetlink.c:3152 page last free pid 5880 tgid 5880 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1258 [inline] __free_frozen_pages+0xb14/0xce0 mm/page_alloc.c:2721 discard_slab mm/slub.c:2730 [inline] __put_partials+0x161/0x1c0 mm/slub.c:3199 put_cpu_partial+0x17c/0x250 mm/slub.c:3274 __slab_free+0x2f7/0x400 mm/slub.c:4526 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4161 [inline] slab_alloc_node mm/slub.c:4210 [inline] __kmalloc_cache_noprof+0x1be/0x3d0 mm/slub.c:4367 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] nsim_fib4_rt_create drivers/net/netdevsim/fib.c:280 [inline] nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:426 [inline] nsim_fib4_event drivers/net/netdevsim/fib.c:464 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:884 [inline] nsim_fib_event_work+0x835/0x3180 drivers/net/netdevsim/fib.c:1493 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88807bf78300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807bf78380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807bf78400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807bf78480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807bf78500: 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: 00 00 add %al,(%rax) 4: 9c pushf 5: 8f 44 24 30 pop 0x30(%rsp) 9: f7 44 24 30 00 02 00 testl $0x200,0x30(%rsp) 10: 00 11: 0f 85 cd 00 00 00 jne 0xe4 17: f7 44 24 08 00 02 00 testl $0x200,0x8(%rsp) 1e: 00 1f: 74 01 je 0x22 21: fb sti 22: 65 48 8b 05 6b f1 d7 mov %gs:0x10d7f16b(%rip),%rax # 0x10d7f195 29: 10 * 2a: 48 3b 44 24 58 cmp 0x58(%rsp),%rax <-- trapping instruction 2f: 0f 85 f2 00 00 00 jne 0x127 35: 48 83 c4 60 add $0x60,%rsp 39: 5b pop %rbx 3a: 41 5c pop %r12 3c: 41 5d pop %r13 3e: 41 5e pop %r14