================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 Write of size 48 at addr ffff888055db6310 by task syz.1.16490/26034 CPU: 1 PID: 26034 Comm: syz.1.16490 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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_ee9fdca00c0e1e15+0x28/0x3d bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x6d1/0x790 kernel/events/core.c:10321 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496 perf_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 do_perf_sw_event kernel/events/core.c:9743 [inline] ___perf_sw_event+0x498/0x6d0 kernel/events/core.c:9774 __perf_sw_event+0x135/0x260 kernel/events/core.c:9786 perf_sw_event include/linux/perf_event.h:1254 [inline] do_user_addr_fault+0x497/0xb20 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:__get_user_4+0x1c/0x30 arch/x86/lib/getuser.S:85 Code: 01 ca c3 90 90 90 90 90 90 90 90 90 90 90 48 ba fd ef ff ff ff 7f 00 00 48 39 d0 0f 83 90 00 00 00 48 19 d2 48 21 d0 0f 01 cb <8b> 10 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 90 90 90 90 90 48 ba RSP: 0018:ffffc9000c2bfd98 EFLAGS: 00050206 RAX: 000000110e22fff6 RBX: ffff888026989c40 RCX: b0a908339c54b100 RDX: ffffffffffffffff RSI: ffffffff8a8c2920 RDI: ffffffff8adee1a0 RBP: ffffc9000c2bfed8 R08: ffffffff8e200f6f R09: 1ffffffff1c401ed R10: dffffc0000000000 R11: fffffbfff1c401ee R12: 00000000c004743e R13: ffff888026989d18 R14: ffff888080f78c80 R15: 1ffff110101ef1c5 ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1071 [inline] ppp_ioctl+0x530/0x1a40 drivers/net/ppp/ppp_generic.c:743 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 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: 0033:0x7fd15799ce59 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:00007fd1587f4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd157c15fa0 RCX: 00007fd15799ce59 RDX: 000000110e22fff6 RSI: 00000000c004743e RDI: 0000000000000009 RBP: 00007fd157a32e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd157c16038 R14: 00007fd157c15fa0 R15: 00007ffd5c5797a8 Allocated by task 26034: 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+0xb2/0x240 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+0x386/0x510 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x524/0xff0 kernel/bpf/syscall.c:1149 __sys_bpf+0x38b/0x780 kernel/bpf/syscall.c:5013 __do_sys_bpf kernel/bpf/syscall.c:5135 [inline] __se_sys_bpf kernel/bpf/syscall.c:5133 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5133 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/0x950 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_ipv6_disable+0x91/0xe0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:163 nf_ct_netns_do_put net/netfilter/nf_conntrack_proto.c:570 [inline] nf_ct_netns_put+0x371/0x510 net/netfilter/nf_conntrack_proto.c:-1 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:2687 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x703/0xba0 net/core/net_namespace.c:640 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888055db6300 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff888055db6300, ffff888055db6340) The buggy address belongs to the physical page: page:ffffea0001576d80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55db6 memcg:ffff888073b61001 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 dead000000000100 dead000000000122 ffff888017442780 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff888073b61001 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 12119, tgid 12119 (syz-executor), ts 2743558930903, free_ts 2743527151051 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560 prep_new_page mm/page_alloc.c:2567 [inline] get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658 alloc_slab_page+0x5d/0x180 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2d0 mm/slub.c:1997 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x126/0x270 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] alloc_fdtable+0xca/0x2c0 fs/file.c:147 dup_fd+0x743/0xa20 fs/file.c:346 copy_files+0x72/0xe0 kernel/fork.c:1642 copy_process+0x1862/0x40c0 kernel/fork.c:2345 kernel_clone+0x24b/0x900 kernel/fork.c:2764 __do_sys_clone kernel/fork.c:2905 [inline] __se_sys_clone kernel/fork.c:2889 [inline] __x64_sys_clone+0x1a7/0x220 kernel/fork.c:2889 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 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x188/0x1e0 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 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/0x490 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa3/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x28a/0x550 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x382/0x610 security/tomoyo/file.c:831 tomoyo_path_symlink+0xa8/0xf0 security/tomoyo/tomoyo.c:199 security_path_symlink+0xdc/0x130 security/security.c:1199 do_symlinkat+0x10c/0x400 fs/namei.c:4503 __do_sys_symlinkat fs/namei.c:4525 [inline] __se_sys_symlinkat fs/namei.c:4522 [inline] __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4522 Memory state around the buggy address: ffff888055db6200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888055db6280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff888055db6300: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff888055db6380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888055db6400: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 01 ca add %ecx,%edx 2: c3 ret 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 48 ba fd ef ff ff ff movabs $0x7fffffffeffd,%rdx 15: 7f 00 00 18: 48 39 d0 cmp %rdx,%rax 1b: 0f 83 90 00 00 00 jae 0xb1 21: 48 19 d2 sbb %rdx,%rdx 24: 48 21 d0 and %rdx,%rax 27: 0f 01 cb stac * 2a: 8b 10 mov (%rax),%edx <-- trapping instruction 2c: 31 c0 xor %eax,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 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: 48 rex.W 3f: ba .byte 0xba