==================================================================
BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
Read of size 2 at addr ffff88806dfa202a 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 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x286/0x870 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:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:sched_core_balance+0x15f/0xf40 kernel/sched/core.c:6382
Code: 0b 00 4c 89 b4 24 80 00 00 00 4c 89 7c 24 60 e9 73 0d 00 00 4c 89 f7 e8 3f 04 ea 09 e8 8a 1c 35 00 fb 48 8b 9c 24 88 00 00 00 <83> fb 08 0f 83 3b 0d 00 00 4c 8d 24 dd 10 fd bd 8d 4c 89 e0 48 c1
RSP: 0018:ffffffff8de07980 EFLAGS: 00000282
RAX: 445e219a598cd600 RBX: 0000000000000000 RCX: 445e219a598cd600
RDX: 0000000000000000 RSI: ffffffff8d9b7d7a RDI: ffffffff8be33780
RBP: ffffffff8de07b20 R08: ffffffff8fa38c37 R09: 1ffffffff1f47186
R10: dffffc0000000000 R11: fffffbfff1f47187 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff8880b8639f80 R15: 0000000000000000
do_balance_callbacks kernel/sched/core.c:5011 [inline]
__balance_callbacks+0x110/0x190 kernel/sched/core.c:5065
__schedule+0x19d8/0x4cc0 kernel/sched/core.c:6968
schedule_idle+0x52/0x90 kernel/sched/core.c:7084
do_idle+0x4ad/0x510 kernel/sched/idle.c:358
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:744
start_kernel+0x3a9/0x410 init/main.c:1097
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
common_startup_64+0x13e/0x147
Allocated by task 9491:
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:388 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396
kmalloc_noprof include/linux/slab.h:905 [inline]
rose_add_node+0x23a/0xde0 net/rose/rose_route.c:85
rose_rt_ioctl+0xa48/0xfb0 net/rose/rose_route.c:740
rose_ioctl+0x3ce/0x8b0 net/rose/af_rose.c:1380
sock_do_ioctl+0xdc/0x300 net/socket.c:1238
sock_ioctl+0x576/0x790 net/socket.c:1359
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:598 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 11315:
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:243 [inline]
__kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kfree+0x18e/0x440 mm/slub.c:4879
rose_rt_device_down+0x473/0x4c0 net/rose/rose_route.c:515
rose_device_event+0x603/0x6a0 net/rose/af_rose.c:248
notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
call_netdevice_notifiers net/core/dev.c:2281 [inline]
__dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1
netif_change_flags+0xe8/0x1a0 net/core/dev.c:9617
dev_change_flags+0x130/0x260 net/core/dev_api.c:68
dev_ioctl+0x7b4/0x1150 net/core/dev_ioctl.c:824
sock_do_ioctl+0x22c/0x300 net/socket.c:1252
sock_ioctl+0x576/0x790 net/socket.c:1359
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:598 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88806dfa2000
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
freed 512-byte region [ffff88806dfa2000, ffff88806dfa2200)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88806dfa3c00 pfn:0x6dfa0
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 ffff88801a441c80 ffffea00014de010 ffffea0001b70f10
raw: ffff88806dfa3c00 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea00014de010 ffffea0001b70f10
head: ffff88806dfa3c00 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0001b7e801 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 5860, tgid 5860 (syz-executor), ts 96435670990, free_ts 87277422964
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
prep_new_page mm/page_alloc.c:1859 [inline]
get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
alloc_slab_page mm/slub.c:2487 [inline]
allocate_slab+0x8a/0x370 mm/slub.c:2655
new_slab mm/slub.c:2709 [inline]
___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
__slab_alloc mm/slub.c:3981 [inline]
__slab_alloc_node mm/slub.c:4056 [inline]
slab_alloc_node mm/slub.c:4217 [inline]
__do_kmalloc_node mm/slub.c:4364 [inline]
__kmalloc_noprof+0x305/0x4f0 mm/slub.c:4377
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+0x142/0x860 net/ipv6/route.c:3811
addrconf_f6i_alloc+0x1d2/0x450 net/ipv6/route.c:4680
fixup_permanent_addr net/ipv6/addrconf.c:3583 [inline]
addrconf_permanent_addr+0x274/0x9d0 net/ipv6/addrconf.c:3622
addrconf_notify+0x887/0x1010 net/ipv6/addrconf.c:3694
notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
call_netdevice_notifiers net/core/dev.c:2281 [inline]
__dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1
netif_change_flags+0xe8/0x1a0 net/core/dev.c:9617
do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3143
page last free pid 5842 tgid 5842 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xdbd/0x1520 mm/page_alloc.c:2952
folios_put_refs+0x559/0x640 mm/swap.c:997
free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:264
__tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
vms_clear_ptes+0x42c/0x540 mm/vma.c:1235
vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1277
do_vmi_align_munmap+0x358/0x420 mm/vma.c:1536
do_vmi_munmap+0x253/0x2e0 mm/vma.c:1584
__vm_munmap+0x23b/0x3d0 mm/vma.c:3155
__do_sys_munmap mm/mmap.c:1080 [inline]
__se_sys_munmap mm/mmap.c:1077 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1077
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88806dfa1f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88806dfa1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88806dfa2000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88806dfa2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88806dfa2100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
vkms_vblank_simulate: vblank timer overrun
----------------
Code disassembly (best guess):
0: 0b 00 or (%rax),%eax
2: 4c 89 b4 24 80 00 00 mov %r14,0x80(%rsp)
9: 00
a: 4c 89 7c 24 60 mov %r15,0x60(%rsp)
f: e9 73 0d 00 00 jmp 0xd87
14: 4c 89 f7 mov %r14,%rdi
17: e8 3f 04 ea 09 call 0x9ea045b
1c: e8 8a 1c 35 00 call 0x351cab
21: fb sti
22: 48 8b 9c 24 88 00 00 mov 0x88(%rsp),%rbx
29: 00
* 2a: 83 fb 08 cmp $0x8,%ebx <-- trapping instruction
2d: 0f 83 3b 0d 00 00 jae 0xd6e
33: 4c 8d 24 dd 10 fd bd lea -0x724202f0(,%rbx,8),%r12
3a: 8d
3b: 4c 89 e0 mov %r12,%rax
3e: 48 rex.W
3f: c1 .byte 0xc1