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BUG: KASAN: slab-use-after-free in rose_get_neigh+0x1b6/0x6f0 net/rose/rose_route.c:692
Read of size 1 at addr ffff888022373030 by task syz.0.772/8942

CPU: 1 UID: 0 PID: 8942 Comm: syz.0.772 Not tainted 6.14.0-rc6-syzkaller-00121-gd9c743b6990b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 rose_get_neigh+0x1b6/0x6f0 net/rose/rose_route.c:692
 rose_connect+0x45a/0x1170 net/rose/af_rose.c:816
 __sys_connect_file net/socket.c:2045 [inline]
 __sys_connect+0x288/0x2d0 net/socket.c:2064
 __do_sys_connect net/socket.c:2070 [inline]
 __se_sys_connect net/socket.c:2067 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2067
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc2d9d8d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fc2dab84038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007fc2d9fa5fa0 RCX: 00007fc2d9d8d169
RDX: 000000000000001c RSI: 0000400000000000 RDI: 0000000000000007
RBP: 00007fc2d9e0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc2d9fa5fa0 R15: 00007ffde8d7d3e8
 </TASK>

Allocated by task 8572:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4325
 kmalloc_noprof include/linux/slab.h:901 [inline]
 rose_add_node+0x209/0xda0 net/rose/rose_route.c:85
 rose_rt_ioctl+0xa6f/0xed0 net/rose/rose_route.c:747
 rose_ioctl+0x3cb/0x9d0 net/rose/af_rose.c:1380
 sock_do_ioctl+0x158/0x460 net/socket.c:1199
 sock_ioctl+0x626/0x8e0 net/socket.c:1318
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 8779:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4609 [inline]
 kfree+0x196/0x430 mm/slub.c:4757
 rose_rt_device_down+0x6e5/0x740 net/rose/rose_route.c:522
 rose_device_event+0x604/0x6a0 net/rose/af_rose.c:248
 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2244 [inline]
 call_netdevice_notifiers net/core/dev.c:2258 [inline]
 dev_close_many+0x33c/0x4c0 net/core/dev.c:1748
 dev_close+0x1c0/0x2c0 net/core/dev.c:1770
 bpq_device_event+0x372/0x8d0 drivers/net/hamradio/bpqether.c:547
 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
 __dev_notify_flags+0x207/0x400
 dev_change_flags+0xf0/0x1a0 net/core/dev.c:9334
 dev_ifsioc+0x7c2/0xe70 net/core/dev_ioctl.c:563
 dev_ioctl+0x719/0x1340 net/core/dev_ioctl.c:826
 sock_do_ioctl+0x240/0x460 net/socket.c:1213
 sock_ioctl+0x626/0x8e0 net/socket.c:1318
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888022373000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 48 bytes inside of
 freed 512-byte region [ffff888022373000, ffff888022373200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888022372800 pfn:0x22370
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 ffff88801b041c80 ffffea0000cd6910 ffffea0001b14e10
raw: ffff888022372800 000000000010000d 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801b041c80 ffffea0000cd6910 ffffea0001b14e10
head: ffff888022372800 000000000010000d 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea000088dc01 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 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 5841, tgid 5841 (syz-executor), ts 76661060009, free_ts 76460364606
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4740
 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:2423 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2587
 new_slab mm/slub.c:2640 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826
 __slab_alloc+0x58/0xa0 mm/slub.c:3916
 __slab_alloc_node mm/slub.c:3991 [inline]
 slab_alloc_node mm/slub.c:4152 [inline]
 __do_kmalloc_node mm/slub.c:4293 [inline]
 __kmalloc_noprof+0x2e6/0x4c0 mm/slub.c:4306
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 fib6_info_alloc+0x2e/0xf0 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x445/0x12c0 net/ipv6/route.c:3767
 ip6_route_add+0x28/0x160 net/ipv6/route.c:3861
 addrconf_prefix_route net/ipv6/addrconf.c:2485 [inline]
 inet6_addr_add+0x7ed/0xe30 net/ipv6/addrconf.c:3050
 inet6_rtm_newaddr+0xa89/0xf10 net/ipv6/addrconf.c:5057
 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6912
 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2533
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1338
page last free pid 5832 tgid 5832 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660
 __slab_free+0x2c2/0x380 mm/slub.c:4520
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4115 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4216
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:596
 alloc_skb include/linux/skbuff.h:1331 [inline]
 nlmsg_new include/net/netlink.h:1018 [inline]
 netlink_ack+0x145/0xa60 net/netlink/af_netlink.c:2470
 netlink_rcv_skb+0x294/0x480 net/netlink/af_netlink.c:2539
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1882
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:733
 __sys_sendto+0x363/0x4c0 net/socket.c:2187
 __do_sys_sendto net/socket.c:2194 [inline]
 __se_sys_sendto net/socket.c:2190 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2190
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888022372f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888022372f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888022373000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888022373080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888022373100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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