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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 ffff888143f83c30 by task syz.2.1348/10887

CPU: 0 UID: 0 PID: 10887 Comm: syz.2.1348 Not tainted 6.14.0-syzkaller-05877-g1a9239bb4253 #0 PREEMPT(full) 
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+0x46b/0x11c0 net/rose/af_rose.c:816
 __sys_connect_file net/socket.c:2038 [inline]
 __sys_connect+0x28c/0x2d0 net/socket.c:2057
 __do_sys_connect net/socket.c:2063 [inline]
 __se_sys_connect net/socket.c:2060 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2060
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f77b218d169
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:00007f77b2ffd038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007f77b23a6160 RCX: 00007f77b218d169
RDX: 000000000000001c RSI: 0000200000000180 RDI: 0000000000000004
RBP: 00007f77b220e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f77b23a6160 R15: 00007ffe2c69bd38
 </TASK>

Allocated by task 9927:
 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+0x9d/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x236/0x370 mm/slub.c:4349
 kmalloc_noprof include/linux/slab.h:902 [inline]
 rose_add_node+0x209/0xdb0 net/rose/rose_route.c:85
 rose_rt_ioctl+0xac2/0xf80 net/rose/rose_route.c:747
 rose_ioctl+0x3ca/0x9e0 net/rose/af_rose.c:1380
 sock_do_ioctl+0x15a/0x490 net/socket.c:1190
 sock_ioctl+0x644/0x900 net/socket.c:1311
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10869:
 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:2376 [inline]
 slab_free mm/slub.c:4633 [inline]
 kfree+0x198/0x430 mm/slub.c:4832
 rose_rt_device_down+0x6e5/0x740 net/rose/rose_route.c:522
 rose_device_event+0x606/0x6a0 net/rose/af_rose.c:248
 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2218 [inline]
 call_netdevice_notifiers net/core/dev.c:2232 [inline]
 dev_close_many+0x33e/0x4c0 net/core/dev.c:1738
 netif_close+0x1c2/0x2d0 net/core/dev.c:1751
 dev_close+0x137/0x280 net/core/dev_api.c:225
 bpq_device_event+0x36a/0x620 drivers/net/hamradio/bpqether.c:528
 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
 __dev_notify_flags+0x209/0x410 net/core/dev.c:-1
 netif_change_flags+0xf0/0x1a0 net/core/dev.c:9438
 dev_change_flags+0x146/0x270 net/core/dev_api.c:68
 dev_ioctl+0x819/0x1380 net/core/dev_ioctl.c:821
 sock_do_ioctl+0x233/0x490 net/socket.c:1204
 sock_ioctl+0x644/0x900 net/socket.c:1311
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888143f83c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 48 bytes inside of
 freed 512-byte region [ffff888143f83c00, ffff888143f83e00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x143f80
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff88801b041c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801b041c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea00050fe001 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 1, tgid 1 (swapper/0), ts 12768453173, free_ts 0
 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+0x3695/0x37e0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x2c5/0x7b0 mm/page_alloc.c:4740
 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2446 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2610
 new_slab mm/slub.c:2663 [inline]
 ___slab_alloc+0xc3b/0x1500 mm/slub.c:3849
 __slab_alloc+0x58/0xa0 mm/slub.c:3939
 __slab_alloc_node mm/slub.c:4014 [inline]
 slab_alloc_node mm/slub.c:4175 [inline]
 __kmalloc_cache_noprof+0x26a/0x370 mm/slub.c:4344
 kmalloc_noprof include/linux/slab.h:902 [inline]
 kzalloc_noprof include/linux/slab.h:1036 [inline]
 device_private_init drivers/base/core.c:3511 [inline]
 device_add+0xc1/0xbf0 drivers/base/core.c:3562
 usb_create_ep_devs+0x130/0x230 drivers/usb/core/endpoint.c:170
 create_intf_ep_devs drivers/usb/core/message.c:1252 [inline]
 usb_set_configuration+0x1ac0/0x1fe0 drivers/usb/core/message.c:2216
 usb_generic_driver_probe+0x88/0x140 drivers/usb/core/generic.c:250
 usb_probe_device+0x1b8/0x380 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2b9/0xad0 drivers/base/dd.c:658
 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800
 driver_probe_device+0x50/0x430 drivers/base/dd.c:830
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888143f83b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888143f83b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888143f83c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888143f83c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888143f83d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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