==================================================================
BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88802349602a by task modprobe/17988

CPU: 0 UID: 0 PID: 17988 Comm: modprobe Not tainted 6.16.0-syzkaller-12063-g37816488247d #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 rose_timer_expiry+0x471/0x4b0
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:unwind_next_frame+0x15/0x2390
Code: 00 eb 88 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 81 ec 98 00 00 00 <49> 89 fe 48 bd 00 00 00 00 00 fc ff df 48 8d 5f 48 48 89 d8 48 c1
RSP: 0018:ffffc900284b6518 EFLAGS: 00000296
RAX: ffffc900284b66d0 RBX: ffffc900284b6648 RCX: 0000000000000001
RDX: ffffc900284b66d8 RSI: dffffc0000000000 RDI: ffffc900284b6648
RBP: 1ffff92005096cca R08: ffffc900284b6601 R09: 0000000000000000
R10: ffffc900284b6648 R11: fffff52005096cd5 R12: ffffc900284b6680
R13: ffffc900284b6658 R14: 1ffff92005096ccb R15: ffffc900284b6650
 __unwind_start+0x5b9/0x760
 arch_stack_walk+0xe4/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_stack+0x3e/0x60
 kasan_record_aux_stack+0xbd/0xd0
 call_rcu+0x157/0x9c0
 mas_wr_store_entry+0x1f1b/0x25b0
 mas_store_prealloc+0xb00/0xf60
 mmap_region+0x1b5e/0x20c0
 do_mmap+0xc45/0x10d0
 vm_mmap_pgoff+0x2a6/0x4d0
 elf_load+0x248/0x6c0
 load_elf_interp+0x4ce/0xb60
 load_elf_binary+0x1a01/0x2740
 bprm_execve+0x99c/0x1450
 kernel_execve+0x8f0/0x9f0
 call_usermodehelper_exec_async+0x210/0x360
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 10825:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 rose_add_node+0x23a/0xde0
 rose_rt_ioctl+0xa48/0xfb0
 rose_ioctl+0x3ce/0x8b0
 sock_do_ioctl+0xdc/0x300
 sock_ioctl+0x576/0x790
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 16715:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 rose_rt_device_down+0x473/0x4c0
 rose_device_event+0x603/0x6a0
 notifier_call_chain+0x1b6/0x3e0
 __dev_notify_flags+0x18d/0x2e0
 netif_change_flags+0xe8/0x1a0
 dev_change_flags+0x130/0x260
 dev_ioctl+0x7b4/0x1150
 sock_do_ioctl+0x22c/0x300
 sock_ioctl+0x576/0x790
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888023496000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff888023496000, ffff888023496200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888023494800 pfn:0x23494
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 ffffea0000bb8d10 ffffea00006ce710
raw: ffff888023494800 0000000000100001 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea0000bb8d10 ffffea00006ce710
head: ffff888023494800 0000000000100001 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00008d2501 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5847, tgid 5847 (syz-executor), ts 47242071805, free_ts 47227188050
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x8a/0x370
 ___slab_alloc+0xbeb/0x1410
 __kmalloc_noprof+0x305/0x4f0
 fib6_info_alloc+0x30/0xf0
 ip6_route_info_create+0x142/0x860
 addrconf_f6i_alloc+0x1d2/0x450
 ipv6_add_addr+0x56e/0x1090
 addrconf_add_linklocal+0x28c/0x6c0
 addrconf_addr_gen+0x490/0x580
 addrconf_init_auto_addrs+0x62d/0xa30
 addrconf_notify+0xacc/0x1010
 notifier_call_chain+0x1b6/0x3e0
page last free pid 5847 tgid 5847 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __slab_free+0x303/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 __alloc_skb+0x112/0x2d0
 netlink_sendmsg+0x5c6/0xb30
 __sock_sendmsg+0x21c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888023495f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888023495f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888023496000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888023496080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888023496100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
