================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 Write of size 72 at addr ffff88802fc6cb10 by task syz.6.947/10012 CPU: 0 PID: 10012 Comm: syz.6.947 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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+0x6bf/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_a448e89f4c9ad9d1+0x30/0x4a bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:616 [inline] bpf_prog_run include/linux/filter.h:623 [inline] bpf_overflow_handler+0x1fc/0x510 kernel/events/core.c:10547 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9718 perf_swevent_overflow kernel/events/core.c:9794 [inline] perf_swevent_event+0x324/0x630 kernel/events/core.c:-1 do_perf_sw_event kernel/events/core.c:9935 [inline] ___perf_sw_event+0x4a7/0x730 kernel/events/core.c:9966 __perf_sw_event+0x139/0x270 kernel/events/core.c:9978 perf_sw_event include/linux/perf_event.h:1442 [inline] do_user_addr_fault+0x123e/0x12c0 arch/x86/mm/fault.c:1278 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:fault_in_readable+0xd0/0x150 mm/gup.c:1905 Code: a6 16 bf ff 4d 89 f4 49 81 cc ff 0f 00 00 4d 89 f7 49 01 dc 49 81 e4 00 f0 ff ff 4d 39 e6 77 44 e8 85 16 bf ff 4d 39 e7 74 47 <41> 8a 07 88 44 24 07 49 81 c7 00 10 00 00 4d 39 e7 74 07 e8 68 16 RSP: 0018:ffffc90013f27af0 EFLAGS: 00050287 RAX: ffffffff81c805db RBX: 0000000000001000 RCX: 0000000000080000 RDX: ffffc9000d0ea000 RSI: 00000000000006cd RDI: 00000000000006ce RBP: dffffc0000000000 R08: ffff88807ebd1e00 R09: 0000000000000002 R10: 0000000000000005 R11: 0000000000000002 R12: 0000200000003000 R13: 0000000000000000 R14: 0000200000002000 R15: 0000200000002000 fault_in_iov_iter_readable+0xbf/0x2e0 lib/iov_iter.c:216 generic_perform_write+0x1f5/0x5c0 mm/filemap.c:4021 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:2883 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x46c/0x990 fs/read_write.c:584 ksys_write+0x150/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7faf7299c799 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:00007faf738ce028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007faf72c15fa0 RCX: 00007faf7299c799 RDX: 00000000002a979d RSI: 0000200000000000 RDI: 0000000000000009 RBP: 00007faf72a32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007faf72c16038 R14: 00007faf72c15fa0 R15: 00007ffc6e38b278 Allocated by task 10012: 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+0xb4/0x230 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+0x33a/0x4c0 kernel/bpf/stackmap.c:114 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5458 __do_sys_bpf kernel/bpf/syscall.c:5580 [inline] __se_sys_bpf kernel/bpf/syscall.c:5578 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5578 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 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 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 nf_unregister_net_hook net/netfilter/core.c:-1 [inline] nf_unregister_net_hooks+0xcb/0x130 net/netfilter/core.c:613 ops_exit_list net/core/net_namespace.c:173 [inline] setup_net+0x7e7/0xa30 net/core/net_namespace.c:375 copy_net_ns+0x36d/0x5e0 net/core/net_namespace.c:520 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x430/0x4a0 kernel/nsproxy.c:179 copy_process+0x1724/0x3d80 kernel/fork.c:2509 kernel_clone+0x24b/0x8a0 kernel/fork.c:2914 __do_sys_clone kernel/fork.c:3057 [inline] __se_sys_clone kernel/fork.c:3041 [inline] __x64_sys_clone+0x1b7/0x230 kernel/fork.c:3041 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 nf_unregister_net_hook net/netfilter/core.c:-1 [inline] nf_unregister_net_hooks+0xcb/0x130 net/netfilter/core.c:613 nf_ct_netns_do_put net/netfilter/nf_conntrack_proto.c:543 [inline] nf_ct_netns_put+0x36d/0x520 net/netfilter/nf_conntrack_proto.c:-1 nf_conncount_destroy+0x41/0x150 net/netfilter/nf_conncount.c:688 ovs_ct_limit_exit net/openvswitch/conntrack.c:1597 [inline] ovs_ct_exit+0x9c/0x200 net/openvswitch/conntrack.c:2000 ovs_exit_net+0xed/0x7a0 net/openvswitch/datapath.c:2686 ops_exit_list net/core/net_namespace.c:173 [inline] cleanup_net+0x70a/0xbb0 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 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 ffff88802fc6cb00 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff88802fc6cb00, ffff88802fc6cb28) The buggy address belongs to the physical page: page:ffffea0000bf1b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2fc6c memcg:ffff888031757401 anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 0000000000000000 0000000000000001 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff888031757401 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5769, tgid 5769 (syz-executor), ts 125383727961, free_ts 124878198508 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/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+0x19e/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] alloc_fdtable+0xca/0x2c0 fs/file.c:147 dup_fd+0x786/0xa50 fs/file.c:346 copy_files+0xc3/0x120 kernel/fork.c:1794 copy_process+0x15ab/0x3d80 kernel/fork.c:2494 kernel_clone+0x24b/0x8a0 kernel/fork.c:2914 __do_sys_clone kernel/fork.c:3057 [inline] __se_sys_clone kernel/fork.c:3041 [inline] __x64_sys_clone+0x1b7/0x230 kernel/fork.c:3041 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 vfree+0x1a6/0x320 mm/vmalloc.c:2868 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:2788 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 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 Memory state around the buggy address: ffff88802fc6ca00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802fc6ca80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff88802fc6cb00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802fc6cb80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802fc6cc00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: bf ff 4d 89 f4 mov $0xf4894dff,%edi 5: 49 81 cc ff 0f 00 00 or $0xfff,%r12 c: 4d 89 f7 mov %r14,%r15 f: 49 01 dc add %rbx,%r12 12: 49 81 e4 00 f0 ff ff and $0xfffffffffffff000,%r12 19: 4d 39 e6 cmp %r12,%r14 1c: 77 44 ja 0x62 1e: e8 85 16 bf ff call 0xffbf16a8 23: 4d 39 e7 cmp %r12,%r15 26: 74 47 je 0x6f * 28: 41 8a 07 mov (%r15),%al <-- trapping instruction 2b: 88 44 24 07 mov %al,0x7(%rsp) 2f: 49 81 c7 00 10 00 00 add $0x1000,%r15 36: 4d 39 e7 cmp %r12,%r15 39: 74 07 je 0x42 3b: e8 .byte 0xe8 3c: 68 .byte 0x68 3d: 16 (bad)