================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 48 at addr ffff888135dc2350 by task syz.4.284/1377 CPU: 0 PID: 1377 Comm: syz.4.284 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 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_6611c23d801ea08d+0x21/0x36 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x3c7/0x5e0 kernel/events/core.c:10273 __perf_event_overflow+0x458/0x640 kernel/events/core.c:9448 perf_swevent_overflow+0x1ae/0x240 kernel/events/core.c:9531 perf_swevent_event+0x3a9/0x440 kernel/events/core.c:-1 do_perf_sw_event kernel/events/core.c:9695 [inline] ___perf_sw_event+0x3bf/0x500 kernel/events/core.c:9726 __perf_sw_event+0x134/0x270 kernel/events/core.c:9738 perf_sw_event include/linux/perf_event.h:1250 [inline] do_user_addr_fault+0xfe9/0x1030 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:__put_user_nocheck_4+0x3/0x11 Code: 00 00 48 39 d9 73 54 0f 01 cb 66 89 01 31 c9 0f 01 ca c3 90 90 90 90 90 48 bb fd ef ff ff ff 7f 00 00 48 39 d9 73 34 0f 01 cb <89> 01 31 c9 0f 01 ca c3 90 90 90 90 90 90 48 bb f9 ef ff ff ff 7f RSP: 0018:ffffc90000a17cb8 EFLAGS: 00050297 RAX: 00000000000000b4 RBX: 00007fffffffeffd RCX: 0000000000000000 RDX: ffffc9000baf9000 RSI: 000000000000fe2e RDI: 000000000000fe2f RBP: ffffc90000a17db0 R08: ffff888132dbd203 R09: 1ffff110265b7a40 R10: dffffc0000000000 R11: ffffed10265b7a41 R12: 0000000020102400 R13: 0000000000000000 R14: ffff888108fd2880 R15: dffffc0000000000 __do_sys_clone kernel/fork.c:3043 [inline] __se_sys_clone kernel/fork.c:3027 [inline] __x64_sys_clone+0x193/0x200 kernel/fork.c:3027 x64_sys_call+0x990/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:57 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: 0033:0x7f6d9a19de99 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:00007f6d9b053fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f6d9a425fa0 RCX: 00007f6d9a19de99 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020102400 RBP: 00007f6d9a233eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f6d9a426038 R14: 00007f6d9a425fa0 R15: 00007ffed76bc208 Allocated by task 1377: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x1f/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+0x398/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x467/0xcf0 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4988 __do_sys_bpf kernel/bpf/syscall.c:5110 [inline] __se_sys_bpf kernel/bpf/syscall.c:5108 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5108 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 ffff888135dc2340 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 16 bytes inside of 32-byte region [ffff888135dc2340, ffff888135dc2360) The buggy address belongs to the physical page: page:ffffea0004d77080 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x135dc2 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004cba2c0 dead000000000002 ffff888100042600 raw: 0000000000000000 0000000000400040 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 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 798, tgid 797 (syz.3.128), ts 34379580350, free_ts 29716764151 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2672 prep_new_page+0x1c/0x110 mm/page_alloc.c:2679 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4586 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5930 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3e0 mm/slub.c:2020 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423 kmalloc_trace+0x29/0xb0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] ref_tracker_alloc+0x16b/0x4a0 lib/ref_tracker.c:85 __netdev_tracker_alloc include/linux/netdevice.h:4085 [inline] netdev_hold include/linux/netdevice.h:4114 [inline] dst_init+0xc4/0x3d0 net/core/dst.c:52 dst_alloc+0x191/0x1e0 net/core/dst.c:96 rt_dst_alloc net/ipv4/route.c:1662 [inline] __mkroute_output net/ipv4/route.c:2628 [inline] ip_route_output_key_hash_rcu+0x13f8/0x2160 net/ipv4/route.c:2850 ip_route_output_key_hash+0x146/0x200 net/ipv4/route.c:2679 __ip_route_output_key include/net/route.h:137 [inline] vti_xmit net/ipv4/ip_vti.c:184 [inline] vti_tunnel_xmit+0x4df/0x1520 net/ipv4/ip_vti.c:304 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1580 [inline] free_pcp_prepare mm/page_alloc.c:1654 [inline] free_unref_page_prepare+0x80c/0x820 mm/page_alloc.c:3621 free_unref_page+0x93/0x530 mm/page_alloc.c:3719 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6020 __vunmap+0xa3c/0xc00 mm/vmalloc.c:2739 __vfree mm/vmalloc.c:2788 [inline] vfree+0x61/0x90 mm/vmalloc.c:2819 kcov_put kernel/kcov.c:437 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:533 __fput+0x1fd/0x8f0 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1e1/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xaf2/0x2850 kernel/exit.c:887 do_group_exit+0x21b/0x2e0 kernel/exit.c:1030 __do_sys_exit_group kernel/exit.c:1041 [inline] __se_sys_exit_group kernel/exit.c:1039 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1039 x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232 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 Memory state around the buggy address: ffff888135dc2200: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc ffff888135dc2280: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc >ffff888135dc2300: 00 00 00 00 fc fc fc fc 00 00 00 fc fc fc fc fc ^ ffff888135dc2380: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc ffff888135dc2400: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 48 39 d9 cmp %rbx,%rcx 5: 73 54 jae 0x5b 7: 0f 01 cb stac a: 66 89 01 mov %ax,(%rcx) d: 31 c9 xor %ecx,%ecx f: 0f 01 ca clac 12: c3 ret 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 48 bb fd ef ff ff ff movabs $0x7fffffffeffd,%rbx 1f: 7f 00 00 22: 48 39 d9 cmp %rbx,%rcx 25: 73 34 jae 0x5b 27: 0f 01 cb stac * 2a: 89 01 mov %eax,(%rcx) <-- trapping instruction 2c: 31 c9 xor %ecx,%ecx 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: 48 rex.W 39: bb f9 ef ff ff mov $0xffffeff9,%ebx 3e: ff (bad) 3f: 7f .byte 0x7f