syzbot

==================================================================
BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183
Read of size 2 at addr ffff888027ad2c2a by task syz.2.348/6540

CPU: 0 PID: 6540 Comm: syz.2.348 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <IRQ>
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc900033778e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 68f1bd661c74af00
RDX: 0000000000000000 RSI: ffffffff8a8c1480 RDI: ffffffff8adefae0
RBP: ffffc900033779e8 R08: dffffc0000000000 R09: fffffbfff215c249
R10: fffffbfff215c249 R11: 1ffffffff215c248 R12: 0000000000000000
R13: 1ffff9200066ef28 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 xa_load+0x80/0x2e0 lib/xarray.c:1461
 memcg_list_lru_allocated mm/list_lru.c:469 [inline]
 memcg_list_lru_alloc+0x11d/0xae0 mm/list_lru.c:483
 memcg_slab_pre_alloc_hook mm/slab.h:494 [inline]
 slab_pre_alloc_hook+0x2b2/0x310 mm/slab.h:715
 slab_alloc_node mm/slub.c:3318 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x49/0x2e0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 shmem_alloc_inode+0x24/0x40 mm/shmem.c:3898
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063
 new_inode+0x25/0x1c0 fs/inode.c:1091
 shmem_get_inode+0x347/0xbf0 mm/shmem.c:2354
 shmem_mknod+0x55/0x1c0 mm/shmem.c:2935
 shmem_mkdir+0x27/0x60 mm/shmem.c:2989
 vfs_mkdir+0x387/0x570 fs/namei.c:4106
 do_mkdirat+0x1d0/0x430 fs/namei.c:4131
 __do_sys_mkdirat fs/namei.c:4146 [inline]
 __se_sys_mkdirat fs/namei.c:4144 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4144
 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
RIP: 0033:0x7fba19d8d457
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 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:00007fba17ff5e68 EFLAGS: 00000202 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fba17ff5ef0 RCX: 00007fba19d8d457
RDX: 00000000000001ff RSI: 00002000000000c0 RDI: 00000000ffffff9c
RBP: 0000200000000080 R08: 0000000000000000 R09: 000000000001f77d
R10: 0000000000000000 R11: 0000000000000202 R12: 00002000000000c0
R13: 00007fba17ff5eb0 R14: 000000000001f783 R15: 0000200000000100
 </TASK>

Allocated by task 6052:
 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
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:936 [inline]
 __kmalloc_node_track_caller+0xae/0x230 mm/slab_common.c:956
 kmalloc_reserve net/core/skbuff.c:446 [inline]
 __alloc_skb+0x22a/0x7e0 net/core/skbuff.c:515
 alloc_skb include/linux/skbuff.h:1271 [inline]
 alloc_skb_with_frags+0xa7/0x710 net/core/skbuff.c:6162
 sock_alloc_send_pskb+0x853/0x980 net/core/sock.c:2750
 sock_alloc_send_skb include/net/sock.h:1926 [inline]
 __ip_append_data+0x253c/0x3760 net/ipv4/ip_output.c:1121
 ip_make_skb+0x1d6/0x3f0 net/ipv4/ip_output.c:1666
 udp_sendmsg+0x1abc/0x2390 net/ipv4/udp.c:1276
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmmsg+0x272/0x490 net/socket.c:2659
 __do_sys_sendmmsg net/socket.c:2688 [inline]
 __se_sys_sendmmsg net/socket.c:2685 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2685
 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 ffff888027ad2c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 512-byte region [ffff888027ad2c00, ffff888027ad2e00)

The buggy address belongs to the physical page:
page:ffffea00009eb400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888027ad1000 pfn:0x27ad0
head:ffffea00009eb400 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea00015c3a08 ffffea000153ff08 ffff888017441c80
raw: ffff888027ad1000 0000000000100002 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 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4349, tgid 4349 (kworker/0:5), ts 72030890982, free_ts 64349476242
 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_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
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc_node_track_caller+0x9e/0x230 mm/slab_common.c:956
 kmalloc_reserve net/core/skbuff.c:446 [inline]
 __alloc_skb+0x22a/0x7e0 net/core/skbuff.c:515
 alloc_skb include/linux/skbuff.h:1271 [inline]
 ndisc_alloc_skb+0xa6/0x450 net/ipv6/ndisc.c:423
 ndisc_send_rs+0x2a2/0x610 net/ipv6/ndisc.c:707
 addrconf_dad_completed+0x792/0xcf0 net/ipv6/addrconf.c:4296
 addrconf_dad_work+0xc3e/0x14d0 net/ipv6/addrconf.c:-1
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa0/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x27e/0x540 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x58e/0x5d0 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x1aa/0x380 security/tomoyo/file.c:771
 security_file_open+0x5e/0xa0 security/security.c:1681
 do_dentry_open+0x305/0x10d0 fs/open.c:869
 do_open fs/namei.c:3626 [inline]
 path_openat+0x25c6/0x2e70 fs/namei.c:3783
 do_filp_open+0x1c1/0x3c0 fs/namei.c:3810
 do_sys_openat2+0x142/0x490 fs/open.c:1318

Memory state around the buggy address:
 ffff888027ad2b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888027ad2b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888027ad2c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888027ad2c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888027ad2d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	00 9c 8f 84 24 80 00 	add    %bl,0x802484(%rdi,%rcx,4)
   7:	00 00                	add    %al,(%rax)
   9:	f6 84 24 81 00 00 00 	testb  $0x2,0x81(%rsp)
  10:	02
  11:	0f 85 f5 00 00 00    	jne    0x10c
  17:	41 f7 c6 00 02 00 00 	test   $0x200,%r14d
  1e:	74 01                	je     0x21
  20:	fb                   	sti
  21:	48 c7 44 24 60 0e 36 	movq   $0x45e0360e,0x60(%rsp)
  28:	e0 45
* 2a:	4b c7 44 3d 00 00 00 	movq   $0x0,0x0(%r13,%r15,1) <-- trapping instruction
  31:	00 00
  33:	66 43 c7 44 3d 09 00 	movw   $0x0,0x9(%r13,%r15,1)
  3a:	00
  3b:	43                   	rex.XB
  3c:	c6                   	.byte 0xc6
  3d:	44                   	rex.R
  3e:	3d                   	.byte 0x3d
  3f:	0b                   	.byte 0xb