================================================================== BUG: KASAN: stack-out-of-bounds in __bpf_get_stack+0x5a9/0xaa0 kernel/bpf/stackmap.c:493 Write of size 96 at addr ffffc9000bf57448 by task syz.4.2835/14811 CPU: 0 UID: 0 PID: 14811 Comm: syz.4.2835 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 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 __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:6858 bpf_stack_liveness_free+0x128/0x230 kernel/bpf/liveness.c:237 bpf_check+0x163ed/0x1c300 kernel/bpf/verifier.c:25391 bpf_prog_load+0x13ba/0x1a10 kernel/bpf/syscall.c:3088 __sys_bpf+0x507/0x860 kernel/bpf/syscall.c:6164 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6272 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1fb3d8f749 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:00007f1fb4c3d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f1fb3fe5fa0 RCX: 00007f1fb3d8f749 RDX: 000000000000004d RSI: 000020000000e000 RDI: 0000000000000005 RBP: 00007f1fb3e13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1fb3fe6038 R14: 00007f1fb3fe5fa0 R15: 00007ffebedd0f98 The buggy address belongs to stack of task syz.4.2835/14811 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 0xffffc9000bf50000 allocated at copy_process+0x4ea/0x3950 kernel/fork.c:2009 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888000000000 pfn:0x7f312 memcg:ffff888029575802 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: ffff888000000000 0000000000000000 00000001ffffffff ffff888029575802 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 14809, tgid 14809 (syz.4.2835), ts 403653457643, free_ts 403606604916 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline] alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2507 vm_area_alloc_pages mm/vmalloc.c:3647 [inline] __vmalloc_area_node mm/vmalloc.c:3724 [inline] __vmalloc_node_range_noprof+0x96c/0x12d0 mm/vmalloc.c:3897 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3960 alloc_thread_stack_node kernel/fork.c:311 [inline] dup_task_struct+0x3c4/0x7b0 kernel/fork.c:880 copy_process+0x4ea/0x3950 kernel/fork.c:2009 kernel_clone+0x21e/0x820 kernel/fork.c:2608 __do_sys_clone3 kernel/fork.c:2910 [inline] __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2889 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 23 tgid 23 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2901 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xd70/0x1870 kernel/rcu/tree.c:2857 handle_softirqs+0x27d/0x850 kernel/softirq.c:622 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:1063 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Memory state around the buggy address: ffffc9000bf57380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000bf57400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc9000bf57480: 00 00 00 00 f1 f1 f1 f1 00 00 f2 f2 00 00 f3 f3 ^ ffffc9000bf57500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000bf57580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================