================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff888031221c2a by task syz.2.1451/10520 CPU: 0 PID: 10520 Comm: syz.2.1451 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x52d/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa9/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 ca 51 14 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 42 ca e3 f6 65 8b 05 b3 18 8c 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc9000cc07580 EFLAGS: 00000206 RAX: 3e738f98cfca9000 RBX: 0000000000000a02 RCX: 3e738f98cfca9000 RDX: dffffc0000000000 RSI: ffffffff8aaaba20 RDI: 0000000000000001 RBP: ffffc9000cc07618 R08: ffffffff90da55af R09: 1ffffffff21b4ab5 R10: dffffc0000000000 R11: fffffbfff21b4ab6 R12: dffffc0000000000 R13: 1ffff110058fce46 R14: ffff88802c7e71d0 R15: 1ffff92001980eb0 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __skb_try_recv_datagram+0x17d/0x4d0 net/core/datagram.c:265 __unix_dgram_recvmsg+0x2d5/0xd60 net/unix/af_unix.c:2410 sock_recvmsg_nosec+0x82/0xd0 net/socket.c:1046 ____sys_recvmsg+0x49b/0x5b0 net/socket.c:2812 ___sys_recvmsg+0x1b6/0x510 net/socket.c:2856 do_recvmmsg+0x360/0x7d0 net/socket.c:2950 __sys_recvmmsg net/socket.c:3029 [inline] __do_sys_recvmmsg net/socket.c:3052 [inline] __se_sys_recvmmsg net/socket.c:3045 [inline] __x64_sys_recvmmsg+0x191/0x240 net/socket.c:3045 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd76798ebe9 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:00007fd7687fd038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fd767bc6090 RCX: 00007fd76798ebe9 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007fd767a11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd767bc6128 R14: 00007fd767bc6090 R15: 00007ffd2e68ad68 Allocated by task 7117: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] rose_add_node+0x23a/0xdd0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa42/0xfb0 net/rose/rose_route.c:740 rose_ioctl+0x3cf/0x8b0 net/rose/af_rose.c:1380 sock_do_ioctl+0xd7/0x2f0 net/socket.c:1222 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x158/0x930 kernel/rcu/tree.c:2837 sctp_destroy_sock+0x1ec/0x370 net/sctp/socket.c:5109 sk_common_release+0x6f/0x310 net/core/sock.c:3728 sctp_close+0x783/0x900 net/sctp/socket.c:1550 inet_release+0x13d/0x180 net/ipv4/af_inet.c:434 __sock_release net/socket.c:659 [inline] sock_close+0xbd/0x230 net/socket.c:1421 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888031221c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff888031221c00, ffff888031221e00) The buggy address belongs to the physical page: page:ffffea0000c48800 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888031220000 pfn:0x31220 head:ffffea0000c48800 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017841c80 ffffea0000b0df10 ffffea0000a28310 raw: ffff888031220000 000000000010000b 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5960, tgid 5959 (syz.0.22), ts 97947148647, free_ts 95158983684 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] fib6_info_alloc+0x32/0xe0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x44f/0x1200 net/ipv6/route.c:3793 addrconf_f6i_alloc+0x1c6/0x400 net/ipv6/route.c:4621 ipv6_add_addr+0x576/0x1090 net/ipv6/addrconf.c:1129 add_addr+0x8c/0x2c0 net/ipv6/addrconf.c:3174 add_v4_addrs+0x70d/0xbc0 net/ipv6/addrconf.c:3236 addrconf_sit_config net/ipv6/addrconf.c:3487 [inline] addrconf_init_auto_addrs+0x39b/0xaa0 net/ipv6/addrconf.c:3525 addrconf_notify+0xb62/0x1010 net/ipv6/addrconf.c:3712 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2122 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2662 put_cpu_partial+0x17c/0x250 mm/slub.c:2738 __slab_free+0x31d/0x410 mm/slub.c:3686 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509 getname_flags+0xbb/0x500 fs/namei.c:140 user_path_at_empty+0x2c/0x60 fs/namei.c:2908 do_readlinkat+0xd8/0x480 fs/stat.c:494 __do_sys_readlink fs/stat.c:527 [inline] __se_sys_readlink fs/stat.c:524 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:524 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff888031221b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888031221b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888031221c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888031221c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888031221d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 ca 51 14 f7 call 0xf71451d1 7: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) e: 00 00 10: 9c pushf 11: 8f 44 24 20 pop 0x20(%rsp) 15: f6 44 24 21 02 testb $0x2,0x21(%rsp) 1a: 75 4b jne 0x67 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 42 ca e3 f6 call 0xf6e3ca71 <-- trapping instruction 2f: 65 8b 05 b3 18 8c 75 mov %gs:0x758c18b3(%rip),%eax # 0x758c18e9 36: 85 c0 test %eax,%eax 38: 74 3c je 0x76 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss