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BUG: KASAN: out-of-bounds in user_mode arch/x86/include/asm/ptrace.h:131 [inline]
BUG: KASAN: out-of-bounds in unwind_next_frame+0x1cd/0x1ea0 arch/x86/kernel/unwind_orc.c:426
Read of size 8 at addr ffff8881eec874c0 by task syz.6.113/860

CPU: 0 PID: 860 Comm: syz.6.113 Not tainted 5.4.289-syzkaller-00030-gcb850525fc3e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x600 mm/kasan/report.c:384
 __kasan_report+0xf3/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 user_mode arch/x86/include/asm/ptrace.h:131 [inline]
 unwind_next_frame+0x1cd/0x1ea0 arch/x86/kernel/unwind_orc.c:426
 arch_stack_walk+0x111/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save_tsk+0x309/0x4b0 kernel/stacktrace.c:151
 proc_pid_stack+0x125/0x1e0 fs/proc/base.c:490
 proc_single_show+0xda/0x160 fs/proc/base.c:801
 seq_read+0x4df/0xe60 fs/seq_file.c:232
 do_loop_readv_writev fs/read_write.c:713 [inline]
 do_iter_read+0x3e8/0x580 fs/read_write.c:935
 vfs_readv fs/read_write.c:997 [inline]
 do_preadv+0x20e/0x350 fs/read_write.c:1089
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f4c95feade9
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:00007f4c94613038 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00007f4c96204160 RCX: 00007f4c95feade9
RDX: 0000000000000332 RSI: 00004000000017c0 RDI: 000000000000000b
RBP: 00007f4c9606c2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4c96204160 R15: 00007fffb86846d8

The buggy address belongs to the page:
page:ffffea0007bb21c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea0007bb21c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x500dc0(GFP_USER|__GFP_ZERO|__GFP_ACCOUNT)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893
 __alloc_pages include/linux/gfp.h:503 [inline]
 __alloc_pages_node include/linux/gfp.h:516 [inline]
 alloc_pages_node include/linux/gfp.h:530 [inline]
 alloc_thread_stack_node kernel/fork.c:259 [inline]
 dup_task_struct+0x85/0x600 kernel/fork.c:886
 copy_process+0x56d/0x3230 kernel/fork.c:1889
 _do_fork+0x197/0x900 kernel/fork.c:2399
 __do_sys_clone kernel/fork.c:2557 [inline]
 __se_sys_clone kernel/fork.c:2538 [inline]
 __x64_sys_clone+0x26b/0x2c0 kernel/fork.c:2538
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x847/0x950 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4955 [inline]
 __free_pages+0x91/0x140 mm/page_alloc.c:4961
 __free_slab+0x221/0x2e0 mm/slub.c:1774
 __slab_free+0x34b/0x360 mm/slub.c:3012
 qlist_free_all+0x43/0xb0 mm/kasan/quarantine.c:167
 quarantine_reduce+0x1d9/0x210 mm/kasan/quarantine.c:260
 __kasan_kmalloc+0x41/0x210 mm/kasan/common.c:507
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 __alloc_skb+0x7a/0x4d0 net/core/skbuff.c:198
 alloc_skb include/linux/skbuff.h:1080 [inline]
 nlmsg_new include/net/netlink.h:888 [inline]
 rtmsg_ifinfo_build_skb+0x81/0x180 net/core/rtnetlink.c:3528
 rollback_registered_many+0xd72/0x1330 net/core/dev.c:8654
 rollback_registered net/core/dev.c:8692 [inline]
 unregister_netdevice_queue+0x333/0x500 net/core/dev.c:9786
 unregister_netdevice include/linux/netdevice.h:2726 [inline]
 __tun_detach+0x8de/0x1390 drivers/net/tun.c:747
 tun_detach drivers/net/tun.c:763 [inline]
 tun_chr_close+0x8f/0x130 drivers/net/tun.c:3563
 __fput+0x262/0x680 fs/file_table.c:281
 task_work_run+0x140/0x170 kernel/task_work.c:113

Memory state around the buggy address:
 ffff8881eec87380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881eec87400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881eec87480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                           ^
 ffff8881eec87500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881eec87580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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