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BUG: KASAN: stack-out-of-bounds in __bpf_get_stack+0x5a9/0xaa0 kernel/bpf/stackmap.c:493
Write of size 152 at addr ffffc900034c7b28 by task syz.3.826/9110

CPU: 0 UID: 0 PID: 9110 Comm: syz.3.826 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:200
 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106
 __bpf_get_stack+0x5a9/0xaa0 kernel/bpf/stackmap.c:493
 ____bpf_get_stack kernel/bpf/stackmap.c:517 [inline]
 bpf_get_stack+0x33/0x50 kernel/bpf/stackmap.c:514
 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1653 [inline]
 bpf_get_stack_raw_tp+0x1a9/0x220 kernel/trace/bpf_trace.c:1643
 bpf_prog_d42cce3539a3fce9+0x3e/0x46
 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline]
 __bpf_prog_run include/linux/filter.h:723 [inline]
 bpf_prog_run include/linux/filter.h:730 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline]
 bpf_trace_run2+0x284/0x4c0 kernel/trace/bpf_trace.c:2116
 __traceiter_kfree+0x2e/0x50 include/trace/events/kmem.h:97
 __do_trace_kfree include/trace/events/kmem.h:97 [inline]
 trace_kfree include/trace/events/kmem.h:97 [inline]
 kfree+0x5ef/0x660 mm/slub.c:6865
 slab_free_after_rcu_debug+0x5d/0x260 mm/slub.c:6716
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core+0xc8e/0x1720 kernel/rcu/tree.c:2857
 handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x60/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x57/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0033:0x7fa1d0054230
Code: f6 48 8b 0f 31 c0 56 48 8d 35 74 b9 19 00 ff 77 18 4c 8b 4f 10 4c 8b 47 08 48 8d 3d 4c 07 1c 00 e8 a5 ab ff ff 0f 1f 44 00 00 <48> 89 f0 48 83 ec 08 4c 8b 4a 28 4c 8b 42 20 48 8b 4a 18 4c 8b 5a
RSP: 002b:00007fa1d1103058 EFLAGS: 00000246
RAX: 00007fa1d02a2eb0 RBX: 00007fa1d03e5fa0 RCX: 00007fa1d0216543
RDX: 00007fa1d03e5fd0 RSI: 0000000000000000 RDI: 0000000000000141
RBP: 00007fa1d0213f91 R08: 7fffffffffffffff R09: 3fffffffffffffff
R10: 4000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa1d03e6038 R14: 00007fa1d03e5fa0 R15: 00007ffca32cfc78
 </TASK>

The buggy address belongs to stack of task syz.3.826/9110
 and is located at offset 296 in frame:
 __bpf_get_stack+0x0/0xaa0 include/linux/mmap_lock.h:-1

This frame has 1 object:
 [32, 36) 'rctx.i'

The buggy address belongs to a 8-page vmalloc region starting at 0xffffc900034c0000 allocated at copy_process+0x4ea/0x3950 kernel/fork.c:2052
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x89c07
memcg:ffff88807dc43c02
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff ffff88807dc43c02
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x29c2(GFP_NOWAIT|__GFP_HIGHMEM|__GFP_IO|__GFP_FS|__GFP_ZERO), pid 9020, tgid 9020 (syz.3.804), ts 191272412781, free_ts 191242535017
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x234/0x290 mm/page_alloc.c:1857
 prep_new_page mm/page_alloc.c:1865 [inline]
 get_page_from_freelist+0x24e0/0x2580 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
 alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2577
 vm_area_alloc_pages mm/vmalloc.c:3649 [inline]
 __vmalloc_area_node mm/vmalloc.c:3863 [inline]
 __vmalloc_node_range_noprof+0x795/0x16a0 mm/vmalloc.c:4051
 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:4111
 alloc_thread_stack_node kernel/fork.c:354 [inline]
 dup_task_struct+0x228/0x9a0 kernel/fork.c:923
 copy_process+0x4ea/0x3950 kernel/fork.c:2052
 kernel_clone+0x21e/0x820 kernel/fork.c:2651
 __do_sys_clone3 kernel/fork.c:2953 [inline]
 __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2932
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5827 tgid 5827 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943
 discard_slab mm/slub.c:3346 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3886
 __slab_free+0x294/0x320 mm/slub.c:5952
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270
 vm_area_dup+0x2b/0x680 mm/vma_init.c:123
 dup_mmap+0x870/0x1b80 mm/mmap.c:1773
 dup_mm kernel/fork.c:1529 [inline]
 copy_mm+0x13c/0x4b0 kernel/fork.c:1581
 copy_process+0x165d/0x3950 kernel/fork.c:2221
 kernel_clone+0x21e/0x820 kernel/fork.c:2651
 __do_sys_clone kernel/fork.c:2792 [inline]
 __se_sys_clone kernel/fork.c:2776 [inline]
 __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2776
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffffc900034c7a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900034c7b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc900034c7b80: f1 f1 f1 f1 00 00 f2 f2 00 00 f3 f3 00 00 00 00
                   ^
 ffffc900034c7c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900034c7c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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