================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6cc/0xcf0 kernel/bpf/stackmap.c:265 Write of size 8 at addr ffff88814d069248 by task syz.3.31/6086 CPU: 0 UID: 0 PID: 6086 Comm: syz.3.31 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __bpf_get_stackid+0x6cc/0xcf0 kernel/bpf/stackmap.c:265 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1628 [inline] bpf_get_stackid_raw_tp+0x196/0x210 kernel/trace/bpf_trace.c:1617 bpf_prog_0269d7a1bf76b886+0x27/0x2f bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline] __bpf_prog_run include/linux/filter.h:721 [inline] bpf_prog_run include/linux/filter.h:728 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2116 __do_trace_kfree include/trace/events/kmem.h:94 [inline] trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x3a0/0x440 mm/slub.c:4881 check_cfg+0x1c82/0x2110 kernel/bpf/verifier.c:17979 bpf_check+0x1fa4/0x1d720 kernel/bpf/verifier.c:24617 bpf_prog_load+0x13ba/0x19e0 kernel/bpf/syscall.c:3062 __sys_bpf+0x507/0x860 kernel/bpf/syscall.c:6134 __do_sys_bpf kernel/bpf/syscall.c:6244 [inline] __se_sys_bpf kernel/bpf/syscall.c:6242 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6242 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd44ab8eec9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd44bab6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fd44ade5fa0 RCX: 00007fd44ab8eec9 RDX: 0000000000000048 RSI: 00002000000054c0 RDI: 0000000000000005 RBP: 00007fd44ac11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd44ade6038 R14: 00007fd44ade5fa0 R15: 00007ffef85e8778 Allocated by task 6086: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4376 [inline] __kmalloc_node_noprof+0x276/0x4e0 mm/slub.c:4382 kmalloc_node_noprof include/linux/slab.h:932 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:395 [inline] bpf_map_area_alloc+0x64/0x180 kernel/bpf/syscall.c:408 prealloc_elems_and_freelist+0x86/0x1d0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x33f/0x4c0 kernel/bpf/stackmap.c:114 map_create+0xaa6/0x1640 kernel/bpf/syscall.c:1497 __sys_bpf+0x5f0/0x860 kernel/bpf/syscall.c:6116 __do_sys_bpf kernel/bpf/syscall.c:6244 [inline] __se_sys_bpf kernel/bpf/syscall.c:6242 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6242 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88814d069000 which belongs to the cache kmalloc-cg-1k of size 1024 The buggy address is located 8 bytes to the right of allocated 576-byte region [ffff88814d069000, ffff88814d069240) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14d068 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88814cf33001 flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 057ff00000000040 ffff88801a44b280 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080100010 00000000f5000000 ffff88814cf33001 head: 057ff00000000040 ffff88801a44b280 dead000000000122 0000000000000000 head: 0000000000000000 0000000080100010 00000000f5000000 ffff88814cf33001 head: 057ff00000000003 ffffea0005341a01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 6075, tgid 6070 (syz.2.27), ts 101106755557, free_ts 80408122284 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_slab_page mm/slub.c:2494 [inline] allocate_slab+0x65/0x370 mm/slub.c:2660 new_slab mm/slub.c:2714 [inline] ___slab_alloc+0xbeb/0x1420 mm/slub.c:3901 __slab_alloc mm/slub.c:3992 [inline] __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] __kmalloc_cache_node_noprof+0x29a/0x3d0 mm/slub.c:4415 kmalloc_node_noprof include/linux/slab.h:928 [inline] alloc_mem_cgroup_per_node_info mm/memcontrol.c:3664 [inline] mem_cgroup_alloc mm/memcontrol.c:3746 [inline] mem_cgroup_css_alloc+0x4b2/0x1f20 mm/memcontrol.c:3791 css_create kernel/cgroup/cgroup.c:5669 [inline] cgroup_apply_control_enable+0x3d4/0xa80 kernel/cgroup/cgroup.c:3289 cgroup_mkdir+0xc40/0xe60 kernel/cgroup/cgroup.c:5893 kernfs_iop_mkdir+0x211/0x350 fs/kernfs/dir.c:1268 vfs_mkdir+0x303/0x510 fs/namei.c:4366 do_mkdirat+0x247/0x590 fs/namei.c:4399 __do_sys_mkdirat fs/namei.c:4416 [inline] __se_sys_mkdirat fs/namei.c:4414 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4414 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5851 tgid 5851 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 discard_slab mm/slub.c:2758 [inline] __put_partials+0x156/0x1a0 mm/slub.c:3223 put_cpu_partial+0x17c/0x250 mm/slub.c:3298 __slab_free+0x2d5/0x3c0 mm/slub.c:4565 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4191 [inline] slab_alloc_node mm/slub.c:4240 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4247 vm_area_dup+0x2b/0x680 mm/vma_init.c:122 __split_vma+0x1a9/0xa00 mm/vma.c:515 vms_gather_munmap_vmas+0x2ea/0x12f0 mm/vma.c:1359 do_vmi_align_munmap+0x25d/0x420 mm/vma.c:1527 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1584 __vm_munmap+0x23b/0x3d0 mm/vma.c:3155 __do_sys_munmap mm/mmap.c:1080 [inline] __se_sys_munmap mm/mmap.c:1077 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1077 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff88814d069100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88814d069180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88814d069200: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff88814d069280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88814d069300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================