================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 Write of size 72 at addr ffff88801ea5fe10 by task syz.1.1688/10478 CPU: 1 PID: 10478 Comm: syz.1.1688 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memcpy+0x3c/0x60 mm/kasan/shadow.c:66 __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x33f/0x400 kernel/bpf/stackmap.c:334 bpf_prog_ceda4e53fcf21ae1+0x28/0x40 bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x522/0x7c0 kernel/events/core.c:10286 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496 do_perf_sw_event kernel/events/core.c:9713 [inline] ___perf_sw_event+0x49e/0x6e0 kernel/events/core.c:9744 __perf_sw_event+0x135/0x260 kernel/events/core.c:9756 perf_sw_event include/linux/perf_event.h:1254 [inline] do_user_addr_fault+0xaea/0xb10 arch/x86/mm/fault.c:1284 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166 Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 a4 31 c0 0f 01 ca c3 89 ca eb 0a 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc9000d677b88 EFLAGS: 00050206 RAX: ffffffff84110b01 RBX: 0000000000000340 RCX: 0000000000000200 RDX: 0000000000000340 RSI: 0000200000002000 RDI: ffff888077a3c140 RBP: 0000000000000000 R08: ffff888077a3c33f R09: 1ffff1100ef47867 R10: dffffc0000000000 R11: ffffed100ef47868 R12: 00007fffffffecc0 R13: 1ffff92001acef8c R14: ffff888077a3c000 R15: 0000200000001ec0 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline] _copy_from_user+0xf4/0x170 lib/usercopy.c:23 copy_from_user include/linux/uaccess.h:161 [inline] bpf_prog_test_run_xdp+0xbf3/0xf10 net/bpf/test_run.c:1397 bpf_prog_test_run+0x31e/0x390 kernel/bpf/syscall.c:3695 __sys_bpf+0x62b/0x780 kernel/bpf/syscall.c:5048 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline] __se_sys_bpf kernel/bpf/syscall.c:5132 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6cd939c799 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:00007f6cda1c0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f6cd9615fa0 RCX: 00007f6cd939c799 RDX: 0000000000000050 RSI: 0000200000000600 RDI: 000000000000000a RBP: 00007f6cd9432c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6cd9616038 R14: 00007f6cd9615fa0 R15: 00007ffc3e2ca538 Allocated by task 10478: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node+0xb0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline] bpf_map_area_alloc+0x47/0xe0 kernel/bpf/syscall.c:341 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x390/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x534/0x1000 kernel/bpf/syscall.c:1149 __sys_bpf+0x38b/0x780 kernel/bpf/syscall.c:5012 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline] __se_sys_bpf kernel/bpf/syscall.c:5132 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849 nf_unregister_net_hook net/netfilter/core.c:-1 [inline] nf_unregister_net_hooks+0xc7/0x130 net/netfilter/core.c:601 nf_defrag_ipv4_disable+0x91/0xe0 net/ipv4/netfilter/nf_defrag_ipv4.c:162 nf_ct_netns_do_put net/netfilter/nf_conntrack_proto.c:562 [inline] nf_ct_netns_put+0x2d6/0x510 net/netfilter/nf_conntrack_proto.c:641 nf_conncount_destroy+0x3d/0x150 net/netfilter/nf_conncount.c:688 ovs_ct_limit_exit net/openvswitch/conntrack.c:1919 [inline] ovs_ct_exit+0x98/0x200 net/openvswitch/conntrack.c:2322 ovs_exit_net+0xe9/0x7a0 net/openvswitch/datapath.c:2655 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x706/0xba0 net/core/net_namespace.c:640 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849 nf_hook_entries_free net/netfilter/core.c:88 [inline] __nf_register_net_hook+0x788/0x910 net/netfilter/core.c:445 nf_register_net_hook+0xae/0x190 net/netfilter/core.c:566 nf_register_net_hooks+0x40/0x1a0 net/netfilter/core.c:582 nf_ct_netns_do_get+0x3bc/0x5b0 net/netfilter/nf_conntrack_proto.c:482 nf_ct_netns_inet_get+0x1f/0x150 net/netfilter/nf_conntrack_proto.c:591 nf_conncount_init+0x123/0x380 net/netfilter/nf_conncount.c:640 ovs_ct_limit_init net/openvswitch/conntrack.c:1902 [inline] ovs_ct_init+0x312/0x480 net/openvswitch/conntrack.c:2311 ovs_init_net+0x1e2/0x240 net/openvswitch/datapath.c:2613 ops_init+0x355/0x5f0 net/core/net_namespace.c:138 setup_net+0x4f2/0xbd0 net/core/net_namespace.c:336 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:508 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226 ksys_unshare+0x4ca/0x8b0 kernel/fork.c:3282 __do_sys_unshare kernel/fork.c:3353 [inline] __se_sys_unshare kernel/fork.c:3351 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3351 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88801ea5fe00 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88801ea5fe00, ffff88801ea5fe40) The buggy address belongs to the physical page: page:ffffea00007a97c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1ea5f memcg:ffff888020da3c01 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0001f2b5c0 dead000000000005 ffff888017442780 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff888020da3c01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x16cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY), pid 3645, tgid 3645 (udevd), ts 18137574013, free_ts 18123819826 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa0/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] inotify_handle_inode_event+0x17c/0x4e0 fs/notify/inotify/inotify_fsnotify.c:96 fsnotify_handle_inode_event fs/notify/fsnotify.c:282 [inline] fsnotify_handle_event fs/notify/fsnotify.c:311 [inline] send_to_group fs/notify/fsnotify.c:385 [inline] fsnotify+0x168c/0x1d00 fs/notify/fsnotify.c:591 __fsnotify_parent+0x683/0x820 fs/notify/fsnotify.c:248 notify_change+0xcbb/0xf40 fs/attr.c:504 chmod_common+0x24e/0x3f0 fs/open.c:606 do_fchmodat+0xd4/0x1a0 fs/open.c:645 __do_sys_chmod fs/open.c:663 [inline] __se_sys_chmod fs/open.c:661 [inline] __x64_sys_chmod+0x5c/0x70 fs/open.c:661 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x11a/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] shmem_alloc_inode+0x24/0x40 mm/shmem.c:3898 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 new_inode+0x25/0x1c0 fs/inode.c:1091 shmem_get_inode+0x347/0xbf0 mm/shmem.c:2354 shmem_mknod+0x55/0x1c0 mm/shmem.c:2935 lookup_open fs/namei.c:3490 [inline] open_last_lookups fs/namei.c:3558 [inline] path_openat+0x1181/0x2ee0 fs/namei.c:3788 do_filp_open+0x1f1/0x430 fs/namei.c:3818 do_sys_openat2+0x150/0x4b0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 Memory state around the buggy address: ffff88801ea5fd00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88801ea5fd80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88801ea5fe00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801ea5fe80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88801ea5ff00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: ff c9 dec %ecx 2: 75 f2 jne 0xfffffff6 4: 89 d1 mov %edx,%ecx 6: c1 e9 03 shr $0x3,%ecx 9: 83 e2 07 and $0x7,%edx c: f3 48 a5 rep movsq %ds:(%rsi),%es:(%rdi) f: 89 d1 mov %edx,%ecx 11: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) 13: 31 c0 xor %eax,%eax 15: 0f 01 ca clac 18: c3 ret 19: 8d 0c ca lea (%rdx,%rcx,8),%ecx 1c: 89 ca mov %ecx,%edx 1e: eb 20 jmp 0x40 20: 0f 01 cb stac 23: 83 fa 40 cmp $0x40,%edx 26: 72 38 jb 0x60 28: 89 d1 mov %edx,%ecx * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: 31 c0 xor %eax,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 89 ca mov %ecx,%edx 34: eb 0a jmp 0x40 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop