================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88805da8942a by task syz.0.507/7729 CPU: 0 PID: 7729 Comm: syz.0.507 Not tainted 6.6.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x200 mm/kasan/report.c:466 kasan_report+0x117/0x150 mm/kasan/report.c:579 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:__kasan_check_write+0x0/0x20 mm/kasan/shadow.c:37 Code: e8 05 ee 84 08 31 ed eb d4 cc f3 0f 1e fa 89 f6 48 8b 0c 24 31 d2 e9 df ea ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 0f 1e fa 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 bc ea ff ff 66 2e RSP: 0018:ffffc900187475f8 EFLAGS: 00000246 RAX: 0000000000000004 RBX: ffffc90018747680 RCX: ffffffff96eaa403 RDX: 1ffffffff1c9564c RSI: 0000000000000008 RDI: ffff88803091cd28 RBP: ffffc900187476f0 R08: ffff88803091cd2f R09: 1ffff110061239a5 R10: dffffc0000000000 R11: ffffed10061239a6 R12: 1ffff920030e8ec4 R13: ffff88803091cd28 R14: 1ffffffff1c9564c R15: 0000000000000000 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_long_try_cmpxchg_release include/linux/atomic/atomic-instrumented.h:4444 [inline] __mutex_unlock_slowpath+0x195/0x6a0 kernel/locking/mutex.c:924 __unix_dgram_recvmsg+0xa0e/0xd60 net/unix/af_unix.c:2491 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: 0033:0x7fb93dd8e9a9 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:00007fb93eca9038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fb93dfb6080 RCX: 00007fb93dd8e9a9 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007fb93de10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb93dfb6080 R15: 00007ffd63fda4a8 Allocated by task 6451: 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 Freed by task 7627: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 rose_rt_device_down+0x43d/0x490 net/rose/rose_route.c:515 rose_device_event+0x604/0x690 net/rose/af_rose.c:248 notifier_call_chain+0x197/0x390 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] __dev_notify_flags+0x18e/0x2e0 net/core/dev.c:-1 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8750 dev_ifsioc+0x6a7/0xe20 net/core/dev_ioctl.c:529 dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786 sock_do_ioctl+0x226/0x2f0 net/socket.c:1236 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 The buggy address belongs to the object at ffff88805da89400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff88805da89400, ffff88805da89600) The buggy address belongs to the physical page: page:ffffea000176a200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805da88800 pfn:0x5da88 head:ffffea000176a200 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 ffffea0000baf710 ffffea0001781410 raw: ffff88805da88800 0000000000100005 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 5791, tgid 5791 (syz-executor), ts 93692130815, free_ts 28641296959 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 ip6_route_add+0x28/0x130 net/ipv6/route.c:3889 addrconf_add_mroute net/ipv6/addrconf.c:2515 [inline] addrconf_add_dev+0x257/0x340 net/ipv6/addrconf.c:2533 inet6_addr_add+0x215/0xb60 net/ipv6/addrconf.c:2996 inet6_rtm_newaddr+0x68d/0x940 net/ipv6/addrconf.c:5004 rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2555 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 free_contig_range+0xa1/0x160 mm/page_alloc.c:6369 destroy_args+0x87/0x770 mm/debug_vm_pgtable.c:1015 debug_vm_pgtable+0x3cc/0x410 mm/debug_vm_pgtable.c:1395 do_one_initcall+0x1fd/0x750 init/main.c:1238 do_initcall_level+0x137/0x1f0 init/main.c:1300 do_initcalls+0x69/0xd0 init/main.c:1316 kernel_init_freeable+0x3d2/0x570 init/main.c:1553 kernel_init+0x1d/0x1c0 init/main.c:1443 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff88805da89300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805da89380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805da89400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805da89480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805da89500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: e8 05 ee 84 08 call 0x884ee0a 5: 31 ed xor %ebp,%ebp 7: eb d4 jmp 0xffffffdd 9: cc int3 a: f3 0f 1e fa endbr64 e: 89 f6 mov %esi,%esi 10: 48 8b 0c 24 mov (%rsp),%rcx 14: 31 d2 xor %edx,%edx 16: e9 df ea ff ff jmp 0xffffeafa 1b: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 22: 00 00 00 25: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 89 f6 mov %esi,%esi 30: 48 8b 0c 24 mov (%rsp),%rcx 34: ba 01 00 00 00 mov $0x1,%edx 39: e9 bc ea ff ff jmp 0xffffeafa 3e: 66 data16 3f: 2e cs