syzbot

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BUG: KASAN: use-after-free in rose_get_neigh+0x1b2/0x6e0 net/rose/rose_route.c:692
Read of size 1 at addr ffff88807b195c30 by task syz.2.12138/31312

CPU: 1 PID: 31312 Comm: syz.2.12138 Not tainted 6.1.132-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:427
 kasan_report+0x136/0x160 mm/kasan/report.c:531
 rose_get_neigh+0x1b2/0x6e0 net/rose/rose_route.c:692
 rose_connect+0x456/0x1160 net/rose/af_rose.c:816
 __sys_connect_file net/socket.c:2011 [inline]
 __sys_connect+0x2c9/0x300 net/socket.c:2028
 __do_sys_connect net/socket.c:2038 [inline]
 __se_sys_connect net/socket.c:2035 [inline]
 __x64_sys_connect+0x76/0x80 net/socket.c:2035
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc1c518d169
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:00007fc1c5fd5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007fc1c53a5fa0 RCX: 00007fc1c518d169
RDX: 000000000000001c RSI: 0000200000000040 RDI: 0000000000000008
RBP: 00007fc1c520e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc1c53a5fa0 R15: 00007ffcb526fa98
 </TASK>

Allocated by task 4469:
 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+0x97/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:563 [inline]
 rose_add_node+0x209/0xda0 net/rose/rose_route.c:85
 rose_rt_ioctl+0xa64/0xec0 net/rose/rose_route.c:747
 rose_ioctl+0x2ca/0x8d0 net/rose/af_rose.c:1380
 sock_do_ioctl+0x152/0x450 net/socket.c:1204
 sock_ioctl+0x484/0x770 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 31312:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 rose_rt_device_down+0x6e1/0x730 net/rose/rose_route.c:522
 rose_device_event+0x5fd/0x690 net/rose/af_rose.c:248
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455
 __dev_notify_flags+0x1fd/0x3f0 net/core/dev.c:-1
 dev_change_flags+0xe7/0x190 net/core/dev.c:8702
 dev_ifsioc+0x177/0x1150 net/core/dev_ioctl.c:327
 dev_ioctl+0x508/0xf70 net/core/dev_ioctl.c:588
 sock_do_ioctl+0x26b/0x450 net/socket.c:1218
 sock_ioctl+0x484/0x770 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88807b195c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 48 bytes inside of
 512-byte region [ffff88807b195c00, ffff88807b195e00)

The buggy address belongs to the physical page:
page:ffffea0001ec6500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7b194
head:ffffea0001ec6500 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017c41c80
raw: 0000000000000000 0000000000100010 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4356, tgid 4356 (kworker/0:5), ts 546629160253, free_ts 546439797578
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4328
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5606
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/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]
 mca_alloc net/ipv6/mcast.c:880 [inline]
 __ipv6_dev_mc_inc+0x426/0xa80 net/ipv6/mcast.c:936
 addrconf_join_solict net/ipv6/addrconf.c:2198 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:4042 [inline]
 addrconf_dad_work+0x444/0x16e0 net/ipv6/addrconf.c:4167
 process_one_work+0x917/0x1260 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
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+0x12a6/0x15b0 mm/page_alloc.c:3384
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3479
 __stack_depot_save+0x409/0x470 lib/stackdepot.c:506
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x60/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x10c/0x2d0 mm/slub.c:3429
 xas_alloc lib/xarray.c:377 [inline]
 xas_create+0x10cf/0x16c0 lib/xarray.c:679
 xas_store+0x9f/0x1960 lib/xarray.c:789
 memcg_list_lru_alloc+0x7ed/0xd20 mm/list_lru.c:520
 memcg_slab_pre_alloc_hook mm/slab.h:494 [inline]
 slab_pre_alloc_hook+0x2a1/0x300 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+0x4a/0x2d0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 alloc_inode fs/inode.c:263 [inline]
 new_inode_pseudo+0x81/0x1d0 fs/inode.c:1063
 __ns_get_path+0x252/0x650 fs/nsfs.c:80
 ns_get_path_cb fs/nsfs.c:118 [inline]
 ns_get_path+0x51/0x90 fs/nsfs.c:144
 proc_ns_get_link+0xf5/0x1f0 fs/proc/namespaces.c:61

Memory state around the buggy address:
 ffff88807b195b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807b195b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807b195c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88807b195c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807b195d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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