==================================================================
BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183
Read of size 2 at addr ffff88802407f02a by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:420
kasan_report+0x10b/0x140 mm/kasan/report.c:524
rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183
call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1504
expire_timers kernel/time/timer.c:1549 [inline]
__run_timers+0x525/0x7c0 kernel/time/timer.c:1820
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:sched_core_balance+0x151/0xdc0 kernel/sched/core.c:6236
Code: 8b 8a e8 f2 cf 09 00 4c 89 7c 24 38 4c 89 6c 24 28 e9 f4 0b 00 00 48 8b 7c 24 40 e8 f9 a7 c6 08 e8 b4 59 2d 00 fb 41 83 fd 08 <0f> 83 c1 0b 00 00 4e 8d 34 fd 80 19 5e 8c 4c 89 f0 48 c1 e8 03 48
RSP: 0018:ffffffff8c807a20 EFLAGS: 00000293
RAX: 1053020adeb31f00 RBX: ffff8880b8e3b7c8 RCX: 1053020adeb31f00
RDX: dffffc0000000000 RSI: ffffffff8a8c0420 RDI: ffffffff8adef6a0
RBP: ffffffff8c807ba0 R08: dffffc0000000000 R09: ffffed10171c7551
R10: ffffed10171c7551 R11: 1ffff110171c7550 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff8880b8e27748 R15: 0000000000000000
do_balance_callbacks kernel/sched/core.c:4892 [inline]
__balance_callbacks+0x103/0x190 kernel/sched/core.c:4946
__schedule+0x1374/0x40b0 kernel/sched/core.c:6566
schedule_idle+0x4a/0x90 kernel/sched/core.c:6665
do_idle+0x525/0x570 kernel/sched/idle.c:331
cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
rest_init+0x2dc/0x300 init/main.c:733
arch_call_rest_init+0xa/0xa init/main.c:893
start_kernel+0x490/0x539 init/main.c:1140
secondary_startup_64_no_verify+0xcf/0xdb
Allocated by task 4619:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:374 [inline]
__kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383
kmalloc include/linux/slab.h:563 [inline]
rose_add_node+0x227/0xdb0 net/rose/rose_route.c:85
rose_rt_ioctl+0xa4c/0xe90 net/rose/rose_route.c:740
rose_ioctl+0x27a/0x790 net/rose/af_rose.c:1380
sock_do_ioctl+0xd3/0x2f0 net/socket.c:1204
sock_ioctl+0x4ed/0x6e0 net/socket.c:1321
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff88802407f000
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
512-byte region [ffff88802407f000, ffff88802407f200)
The buggy address belongs to the physical page:
page:ffffea0000901f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802407f000 pfn:0x2407c
head:ffffea0000901f00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea000158b508 ffffea000098cc08 ffff888017441c80
raw: ffff88802407f000 000000000010000f 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 6053257128, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532
prep_new_page mm/page_alloc.c:2539 [inline]
get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328
__alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614
alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2115
alloc_slab_page+0x5d/0x160 mm/slub.c:1794
allocate_slab mm/slub.c:1939 [inline]
new_slab+0x87/0x2c0 mm/slub.c:1992
___slab_alloc+0xbc6/0x1220 mm/slub.c:3180
__slab_alloc mm/slub.c:3279 [inline]
slab_alloc_node mm/slub.c:3364 [inline]
__kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3437
kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026
kmalloc include/linux/slab.h:563 [inline]
kzalloc include/linux/slab.h:699 [inline]
device_private_init drivers/base/core.c:3541 [inline]
device_add+0xba/0xfb0 drivers/base/core.c:3591
tty_register_device_attr+0x40a/0x920 drivers/tty/tty_io.c:3250
tty_register_device drivers/tty/tty_io.c:3185 [inline]
tty_register_driver+0x596/0xb10 drivers/tty/tty_io.c:3449
legacy_pty_init+0x3c1/0x5fd drivers/tty/pty.c:581
pty_init+0xa/0x12 drivers/tty/pty.c:943
do_one_initcall+0x214/0x7a0 init/main.c:1298
do_initcall_level+0x137/0x1e4 init/main.c:1371
page_owner free stack trace missing
Memory state around the buggy address:
ffff88802407ef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802407ef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802407f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802407f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802407f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 8b 8a e8 f2 cf 09 mov 0x9cff2e8(%rdx),%ecx
6: 00 4c 89 7c add %cl,0x7c(%rcx,%rcx,4)
a: 24 38 and $0x38,%al
c: 4c 89 6c 24 28 mov %r13,0x28(%rsp)
11: e9 f4 0b 00 00 jmp 0xc0a
16: 48 8b 7c 24 40 mov 0x40(%rsp),%rdi
1b: e8 f9 a7 c6 08 call 0x8c6a819
20: e8 b4 59 2d 00 call 0x2d59d9
25: fb sti
26: 41 83 fd 08 cmp $0x8,%r13d
* 2a: 0f 83 c1 0b 00 00 jae 0xbf1 <-- trapping instruction
30: 4e 8d 34 fd 80 19 5e lea -0x73a1e680(,%r15,8),%r14
37: 8c
38: 4c 89 f0 mov %r14,%rax
3b: 48 c1 e8 03 shr $0x3,%rax
3f: 48 rex.W