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BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x3a4/0x760 arch/x86/kernel/unwind_frame.c:305
Read of size 8 at addr ffff8881e0affd88 by task syz.0.27/585

CPU: 0 PID: 585 Comm: syz.0.27 Not tainted 5.4.292-syzkaller-05062-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 __dump_stack+0x1e/0x20 lib/dump_stack.c:77
 dump_stack+0x15b/0x1b8 lib/dump_stack.c:118
 print_address_description+0x8d/0x4c0 mm/kasan/report.c:384
 __kasan_report+0xef/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 unwind_next_frame+0x3a4/0x760 arch/x86/kernel/unwind_frame.c:305
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save_tsk+0x1e8/0x2b0 kernel/stacktrace.c:151
 proc_pid_stack+0x12e/0x200 fs/proc/base.c:490
 proc_single_show+0xdc/0x170 fs/proc/base.c:801
 seq_read+0x540/0xe50 fs/seq_file.c:232
 do_loop_readv_writev include/linux/uio.h:110 [inline]
 do_iter_read+0x44b/0x5d0 fs/read_write.c:935
 vfs_readv fs/read_write.c:997 [inline]
 do_preadv+0x1f6/0x330 fs/read_write.c:1089
 __do_sys_preadv fs/read_write.c:1139 [inline]
 __se_sys_preadv fs/read_write.c:1134 [inline]
 __x64_sys_preadv+0x9e/0xb0 fs/read_write.c:1134
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fd5ae2a6de9
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:00007fd5adcf8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00007fd5ae4c0080 RCX: 00007fd5ae2a6de9
RDX: 0000000000000332 RSI: 00004000000017c0 RDI: 0000000000000005
RBP: 00007fd5ae3282a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd5ae4c0080 R15: 00007ffe6b837668

The buggy address belongs to the page:
page:ffffea000782bfc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea000782bfc8 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+0x35e/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x1296/0x1310 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x202/0x4b0 mm/page_alloc.c:4894
 __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+0x91/0x640 kernel/fork.c:886
 copy_process+0x503/0x2cf0 kernel/fork.c:1889
 _do_fork+0x190/0x860 kernel/fork.c:2399
 __do_sys_clone kernel/fork.c:2557 [inline]
 __se_sys_clone kernel/fork.c:2538 [inline]
 __x64_sys_clone+0x12e/0x160 kernel/fork.c:2538
 do_syscall_64+0xcf/0x170 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+0x7e4/0x910 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4956 [inline]
 __free_pages+0x8c/0x110 mm/page_alloc.c:4962
 free_thread_stack kernel/fork.c:299 [inline]
 release_task_stack kernel/fork.c:439 [inline]
 put_task_stack+0x21b/0x260 kernel/fork.c:450
 finish_task_switch+0x245/0x590 kernel/sched/core.c:3481
 context_switch kernel/sched/core.c:3613 [inline]
 __schedule+0xa57/0x12a0 kernel/sched/core.c:4309
 preempt_schedule_common+0x9b/0xf0 kernel/sched/core.c:4458
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:4483
 ___preempt_schedule+0x16/0x20 arch/x86/entry/thunk_64.S:50
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
 _raw_spin_unlock_irq+0x61/0x70 kernel/locking/spinlock.c:199
 spin_unlock_irq include/linux/spinlock.h:388 [inline]
 do_group_exit+0x242/0x300 kernel/exit.c:981
 __do_sys_exit_group kernel/exit.c:995 [inline]
 __se_sys_exit_group kernel/exit.c:993 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:993
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881e0affc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881e0affd00: f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 00 f3 f3
>ffff8881e0affd80: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
                      ^
 ffff8881e0affe00: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3
 ffff8881e0affe80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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