==================================================================
BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183
Read of size 2 at addr ffff888079d8282a by task swapper/1/0
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
print_address_description+0x60/0x2d0 mm/kasan/report.c:248
__kasan_report mm/kasan/report.c:434 [inline]
kasan_report+0xdf/0x130 mm/kasan/report.c:451
rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183
call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
expire_timers kernel/time/timer.c:1699 [inline]
__run_timers+0x53e/0x800 kernel/time/timer.c:1970
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
handle_softirqs+0x339/0x830 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:730
Code: b7 48 89 df e8 76 29 f8 f7 eb ad e8 4f af f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 97 a5 5f 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000d67d48 EFLAGS: 000002c2
RAX: d7c8d5f96d675f00 RBX: ffff888017978000 RCX: d7c8d5f96d675f00
RDX: 0000000000000001 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe40
RBP: ffffc90000d67e80 R08: ffff8880b913b30b R09: 1ffff11017227661
R10: dffffc0000000000 R11: ffffed1017227662 R12: 1ffff920001acfb4
R13: dffffc0000000000 R14: 1ffff11002f2f000 R15: 0000000000000000
default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
cpuidle_idle_call kernel/sched/idle.c:202 [inline]
do_idle+0x3a1/0x650 kernel/sched/idle.c:326
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:424
start_secondary+0x330/0x430 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xb1/0xbb
Allocated by task 4686:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
____kasan_kmalloc mm/kasan/common.c:513 [inline]
__kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522
kmalloc include/linux/slab.h:607 [inline]
rose_add_node+0x227/0xdb0 net/rose/rose_route.c:85
rose_rt_ioctl+0xa2b/0xe70 net/rose/rose_route.c:738
rose_ioctl+0x2a7/0x7d0 net/rose/af_rose.c:1377
sock_do_ioctl+0xfb/0x320 net/socket.c:1147
sock_ioctl+0x4d2/0x710 net/socket.c:1266
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
The buggy address belongs to the object at ffff888079d82800
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
512-byte region [ffff888079d82800, ffff888079d82a00)
The buggy address belongs to the page:
page:ffffea0001e76000 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888079d82800 pfn:0x79d80
head:ffffea0001e76000 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea000183e908 ffffea0001825f08 ffff888016c41c80
raw: ffff888079d82800 000000000010000a 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 4192, ts 64749674211, free_ts 64737620008
prep_new_page mm/page_alloc.c:2426 [inline]
get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192
__alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
alloc_slab_page mm/slub.c:1780 [inline]
allocate_slab mm/slub.c:1917 [inline]
new_slab+0xc0/0x4b0 mm/slub.c:1980
___slab_alloc+0x80a/0xdd0 mm/slub.c:3013
__slab_alloc mm/slub.c:3100 [inline]
slab_alloc_node mm/slub.c:3191 [inline]
slab_alloc mm/slub.c:3233 [inline]
kmem_cache_alloc_trace+0x1a5/0x2a0 mm/slub.c:3250
kmalloc include/linux/slab.h:607 [inline]
kzalloc include/linux/slab.h:738 [inline]
mca_alloc net/ipv6/mcast.c:880 [inline]
__ipv6_dev_mc_inc+0x3fa/0xa90 net/ipv6/mcast.c:935
ipv6_add_dev+0xcd8/0x1190 net/ipv6/addrconf.c:467
addrconf_notify+0x66f/0xf00 net/ipv6/addrconf.c:3576
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
call_netdevice_notifiers_extack net/core/dev.c:2074 [inline]
call_netdevice_notifiers net/core/dev.c:2088 [inline]
register_netdevice+0x12a6/0x1710 net/core/dev.c:10454
register_netdev+0x37/0x50 net/core/dev.c:10547
ip6gre_init_net+0x21f/0x2f0 net/ipv6/ip6_gre.c:1635
ops_init+0x357/0x600 net/core/net_namespace.c:138
setup_net+0x39e/0xa10 net/core/net_namespace.c:333
copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503
create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
page last free stack trace:
create_dummy_stack mm/page_owner.c:59 [inline]
register_dummy_stack+0x95/0xf0 mm/page_owner.c:65
init_page_owner+0x25/0x750 mm/page_owner.c:83
kernel_init_freeable+0x3e4/0x570 init/main.c:1627
kernel_init+0x19/0x1b0 init/main.c:1520
Memory state around the buggy address:
ffff888079d82700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888079d82780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888079d82800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888079d82880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888079d82900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: b7 48 mov $0x48,%bh
2: 89 df mov %ebx,%edi
4: e8 76 29 f8 f7 call 0xf7f8297f
9: eb ad jmp 0xffffffb8
b: e8 4f af f6 ff call 0xfff6af5f
10: 00 00 add %al,(%rax)
12: cc int3
13: cc int3
14: 00 00 add %al,(%rax)
16: cc int3
17: cc int3
18: 00 00 add %al,(%rax)
1a: cc int3
1b: cc int3
1c: 00 00 add %al,(%rax)
1e: cc int3
1f: 66 90 xchg %ax,%ax
21: 0f 00 2d 97 a5 5f 00 verw 0x5fa597(%rip) # 0x5fa5bf
28: fb sti
29: f4 hlt
* 2a: c3 ret <-- trapping instruction
2b: 0f 1f 40 00 nopl 0x0(%rax)
2f: 41 57 push %r15
31: 41 56 push %r14
33: 53 push %rbx
34: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14
3b: fc ff df
3e: 65 gs
3f: 48 rex.W