================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271 Write of size 32 at addr ffff88802735a510 by task syz.3.1319/9309 CPU: 1 PID: 9309 Comm: syz.3.1319 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x241/0x290 mm/kasan/generic.c:187 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:362 [inline] bpf_get_stackid_pe+0x343/0x410 kernel/bpf/stackmap.c:331 bpf_prog_c1fc8cdcea84755f+0x30/0x48 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:617 [inline] bpf_prog_run include/linux/filter.h:624 [inline] bpf_overflow_handler+0x1fc/0x510 kernel/events/core.c:10576 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9712 perf_event_overflow kernel/events/core.c:9733 [inline] perf_swevent_hrtimer+0x437/0x610 kernel/events/core.c:11222 __run_hrtimer kernel/time/hrtimer.c:1754 [inline] __hrtimer_run_queues+0x4e8/0xc10 kernel/time/hrtimer.c:1818 hrtimer_interrupt+0x39d/0x980 kernel/time/hrtimer.c:1880 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__syscall_enter_from_user_work kernel/entry/common.c:97 [inline] RIP: 0010:syscall_enter_from_user_mode+0x2e/0x80 kernel/entry/common.c:118 Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 e9 fa ff ff 66 90 66 90 e8 40 d2 fe f6 e8 fb d1 fe f6 fb 65 48 8b 05 22 a7 74 75 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 3d 11 e5 f6 48 RSP: 0018:ffffc90019c77f08 EFLAGS: 00000286 RAX: ffff888031481e00 RBX: 0000000000000101 RCX: 01c4585e49057a00 RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: ffffffff8b1d32e0 RBP: ffffc90019c77f48 R08: ffffffff8e8c772f R09: 1ffffffff1d18ee5 R10: dffffc0000000000 R11: fffffbfff1d18ee6 R12: 0000000000000000 R13: 0000000000000000 R14: ffffc90019c77f58 R15: 0000000000000000 do_syscall_64+0x28/0xb0 arch/x86/entry/common.c:72 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe6d239e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe6d3333028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe6d2625fa0 RCX: 00007fe6d239e0d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffff9c RBP: 00007fe6d2435024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe6d2626038 R14: 00007fe6d2625fa0 R15: 00007ffda15dec18 Allocated by task 9309: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node+0xb6/0x240 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:303 [inline] bpf_map_area_alloc+0x5e/0x110 kernel/bpf/syscall.c:316 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x32b/0x4b0 kernel/bpf/stackmap.c:114 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5460 __do_sys_bpf kernel/bpf/syscall.c:5582 [inline] __se_sys_bpf kernel/bpf/syscall.c:5580 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5580 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x780 kernel/rcu/tree.c:3452 drop_sysctl_table+0x394/0x540 fs/proc/proc_sysctl.c:1515 unregister_sysctl_table+0x41/0x60 fs/proc/proc_sysctl.c:1536 retire_ipc_sysctls+0x5e/0x80 ipc/ipc_sysctl.c:312 free_ipc_ns ipc/namespace.c:160 [inline] free_ipc+0x12f/0x270 ipc/namespace.c:181 process_one_work kernel/workqueue.c:2657 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x780 kernel/rcu/tree.c:3452 drop_sysctl_table+0x394/0x540 fs/proc/proc_sysctl.c:1515 unregister_sysctl_table+0x41/0x60 fs/proc/proc_sysctl.c:1536 retire_ipc_sysctls+0x5e/0x80 ipc/ipc_sysctl.c:312 free_ipc_ns ipc/namespace.c:160 [inline] free_ipc+0x12f/0x270 ipc/namespace.c:181 process_one_work kernel/workqueue.c:2657 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88802735a400 which belongs to the cache kmalloc-cg-512 of size 512 The buggy address is located 272 bytes inside of allocated 288-byte region [ffff88802735a400, ffff88802735a520) The buggy address belongs to the physical page: page:ffffea00009cd600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27358 head:ffffea00009cd600 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff8880304c1501 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c4f140 ffffea0001f55b00 dead000000000002 raw: 0000000000000000 0000000080100010 00000001ffffffff ffff8880304c1501 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 5153, tgid 5153 (udevd), ts 29619138348, free_ts 29578781530 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_slab_page+0x5d/0x180 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node_track_caller+0xa4/0x230 mm/slab_common.c:1027 kmalloc_reserve+0x116/0x240 net/core/skbuff.c:584 __alloc_skb+0x138/0x2c0 net/core/skbuff.c:653 alloc_skb include/linux/skbuff.h:1316 [inline] alloc_skb_with_frags+0xcd/0x7a0 net/core/skbuff.c:6353 sock_alloc_send_pskb+0x883/0x9a0 net/core/sock.c:2830 unix_dgram_sendmsg+0x5a9/0x16e0 net/unix/af_unix.c:2003 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x2dc/0x420 net/socket.c:1161 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_write+0x151/0x260 fs/read_write.c:637 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1182 [inline] free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x319/0x400 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:770 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x17e/0x2c0 mm/slub.c:3519 getname_flags+0xbb/0x500 fs/namei.c:140 do_sys_openat2+0xda/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88802735a400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802735a480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88802735a500: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802735a580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802735a600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 41 56 push %r14 2: 53 push %rbx 3: 48 89 f3 mov %rsi,%rbx 6: 49 89 fe mov %rdi,%r14 9: 48 8b 7c 24 10 mov 0x10(%rsp),%rdi e: e8 e9 fa ff ff call 0xfffffafc 13: 66 90 xchg %ax,%ax 15: 66 90 xchg %ax,%ax 17: e8 40 d2 fe f6 call 0xf6fed25c 1c: e8 fb d1 fe f6 call 0xf6fed21c 21: fb sti 22: 65 48 8b 05 22 a7 74 mov %gs:0x7574a722(%rip),%rax # 0x7574a74c 29: 75 * 2a: 48 8b 70 08 mov 0x8(%rax),%rsi <-- trapping instruction 2e: 40 f6 c6 3f test $0x3f,%sil 32: 74 0b je 0x3f 34: 4c 89 f7 mov %r14,%rdi 37: 5b pop %rbx 38: 41 5e pop %r14 3a: e9 3d 11 e5 f6 jmp 0xf6e5117c 3f: 48 rex.W