================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 72 at addr ffff888112370890 by task syz.3.122/722 CPU: 1 PID: 722 Comm: syz.3.122 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189 memcpy+0x44/0x70 mm/kasan/shadow.c:66 __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x2ee/0x400 kernel/bpf/stackmap.c:334 bpf_prog_02c92f715e75ceb8+0x28/0x3d bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x51f/0x5e0 kernel/events/core.c:10238 __perf_event_overflow+0x437/0x620 kernel/events/core.c:9448 perf_swevent_overflow kernel/events/core.c:9524 [inline] perf_swevent_event+0x2f7/0x530 kernel/events/core.c:-1 do_perf_sw_event kernel/events/core.c:9665 [inline] ___perf_sw_event+0x3bf/0x4f0 kernel/events/core.c:9696 __perf_sw_event+0x134/0x270 kernel/events/core.c:9708 perf_sw_event include/linux/perf_event.h:1250 [inline] do_user_addr_fault+0xffb/0x1050 arch/x86/mm/fault.c:1285 handle_page_fault arch/x86/mm/fault.c:1464 [inline] exc_page_fault+0x51/0xb0 arch/x86/mm/fault.c:1517 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:copy_user_short_string+0xa/0x40 arch/x86/lib/copy_user_64.S:232 Code: 83 f8 12 74 0a 89 d1 f3 a4 89 c8 0f 01 ca c3 89 d0 0f 01 ca c3 01 ca eb e7 90 90 90 90 90 90 90 89 d1 83 e2 07 c1 e9 03 74 12 <4c> 8b 06 4c 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10 RSP: 0018:ffffc9000114faa0 EFLAGS: 00050202 RAX: ffffffff82689a01 RBX: 0000000000000010 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000300 RDI: ffffc9000e15d050 RBP: ffffc9000114fac8 R08: ffffc9000e15d05f R09: 1ffff92001c2ba0b R10: dffffc0000000000 R11: fffff52001c2ba0c R12: 00007fffffffeff0 R13: 0000000000000300 R14: ffffc9000e15d050 R15: 0000000000000300 copy_from_user include/linux/uaccess.h:161 [inline] __get_filter+0x167/0x410 net/core/filter.c:1510 sk_attach_filter+0x23/0x140 net/core/filter.c:1541 tun_attach+0x368/0x1460 drivers/net/tun.c:784 tun_set_iff+0x49d/0xe90 drivers/net/tun.c:2776 __tun_chr_ioctl+0x89b/0x1e90 drivers/net/tun.c:3114 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3401 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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: 0033:0x7f6e6199c819 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:00007f6e628fd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6e61c15fa0 RCX: 00007f6e6199c819 RDX: 0000200000002280 RSI: 00000000400454ca RDI: 000000000000000c RBP: 00007f6e61a32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6e61c16038 R14: 00007f6e61c15fa0 R15: 00007ffedadcb058 Allocated by task 722: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:380 [inline] __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:389 kasan_kmalloc include/linux/kasan.h:212 [inline] __do_kmalloc_node mm/slab_common.c:938 [inline] __kmalloc_node+0xb2/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline] bpf_map_area_alloc+0x4b/0xe0 kernel/bpf/syscall.c:341 prealloc_elems_and_freelist+0x8a/0x1e0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x3a7/0x530 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x49c/0xd80 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4987 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5107 x64_sys_call+0x488/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 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 ffff888112370880 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff888112370880, ffff8881123708c0) The buggy address belongs to the physical page: page:ffffea000448dc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x112370 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004c96180 dead000000000004 ffff888100042780 raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 283, tgid 283 (syz-executor), ts 23930969720, free_ts 23921065826 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670 prep_new_page+0x1c/0x110 mm/page_alloc.c:2677 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5924 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423 kmalloc_trace+0x29/0xb0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] call_modprobe kernel/kmod.c:79 [inline] __request_module+0x2a7/0x910 kernel/kmod.c:170 dev_load+0x5b/0xb0 net/core/dev_ioctl.c:435 dev_ioctl+0x3a2/0xcf0 net/core/dev_ioctl.c:500 sock_do_ioctl+0x252/0x330 net/socket.c:1205 sock_ioctl+0x4bd/0x710 net/socket.c:1310 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1578 [inline] free_pcp_prepare mm/page_alloc.c:1652 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3618 free_unref_page+0x95/0x540 mm/page_alloc.c:3716 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6014 __free_slab+0xca/0x1a0 mm/slub.c:2044 free_slab mm/slub.c:2059 [inline] discard_slab mm/slub.c:2065 [inline] __unfreeze_partials+0x160/0x190 mm/slub.c:2614 put_cpu_partial+0xa9/0x100 mm/slub.c:2690 __slab_free+0x1c4/0x280 mm/slub.c:3589 do_slab_free mm/slub.c:3666 [inline] ___cache_free+0xbf/0xd0 mm/slub.c:3722 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:311 kasan_slab_alloc include/linux/kasan.h:202 [inline] slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768 slab_alloc_node mm/slub.c:3382 [inline] __kmem_cache_alloc_node+0x192/0x2c0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc_node+0xa1/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] kzalloc_node include/linux/slab.h:710 [inline] qdisc_alloc+0x79/0x780 net/sched/sch_generic.c:951 qdisc_create_dflt+0x6b/0x3b0 net/sched/sch_generic.c:1009 Memory state around the buggy address: ffff888112370780: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff888112370800: 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc fc >ffff888112370880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff888112370900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888112370980: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 83 f8 12 cmp $0x12,%eax 3: 74 0a je 0xf 5: 89 d1 mov %edx,%ecx 7: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) 9: 89 c8 mov %ecx,%eax b: 0f 01 ca clac e: c3 ret f: 89 d0 mov %edx,%eax 11: 0f 01 ca clac 14: c3 ret 15: 01 ca add %ecx,%edx 17: eb e7 jmp 0x0 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 89 d1 mov %edx,%ecx 22: 83 e2 07 and $0x7,%edx 25: c1 e9 03 shr $0x3,%ecx 28: 74 12 je 0x3c * 2a: 4c 8b 06 mov (%rsi),%r8 <-- trapping instruction 2d: 4c 89 07 mov %r8,(%rdi) 30: 48 8d 76 08 lea 0x8(%rsi),%rsi 34: 48 8d 7f 08 lea 0x8(%rdi),%rdi 38: ff c9 dec %ecx 3a: 75 ee jne 0x2a 3c: 21 d2 and %edx,%edx 3e: 74 10 je 0x50