================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6cc/0xcf0 kernel/bpf/stackmap.c:265 Write of size 8 at addr ffff88804e69aa48 by task syz.2.134/6528 CPU: 0 UID: 0 PID: 6528 Comm: syz.2.134 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:1810 [inline] bpf_get_stackid_raw_tp+0x196/0x210 kernel/trace/bpf_trace.c:1799 bpf_prog_b724608cae728045+0x27/0x2f bpf_dispatcher_nop_func include/linux/bpf.h:1335 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline] bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2298 __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 slab_free_after_rcu_debug+0x60/0x2a0 mm/slub.c:4732 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5225 Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 df c4 eb 09 e8 ea 41 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc9000e19e618 EFLAGS: 00000286 RAX: cb8c3cfdf83d5c00 RBX: 0000000000000000 RCX: cb8c3cfdf83d5c00 RDX: 0000000000000000 RSI: ffffffff8d9ba186 RDI: ffffffff8be33e00 RBP: ffffc9000e19e670 R08: ffffffff8fa3a837 R09: 1ffffffff1f47506 R10: dffffc0000000000 R11: fffffbfff1f47507 R12: ffff88807d50bc00 R13: dffffc0000000000 R14: ffff888032ed9e00 R15: ffff8880b863ab58 context_switch kernel/sched/core.c:5360 [inline] __schedule+0x17a0/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5893 Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 0b 4d 03 11 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000e19ea10 EFLAGS: 00000206 RAX: cb8c3cfdf83d5c00 RBX: 0000000000000202 RCX: cb8c3cfdf83d5c00 RDX: 0000000000000000 RSI: ffffffff8dba9858 RDI: ffffffff8be33e00 RBP: ffff88807d50c6f0 R08: ffffc9000e19f018 R09: 0000000000000000 R10: ffffc9000e19eb98 R11: fffff52001c33d75 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8e13a120 R15: ffff88807d50bc00 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1169 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 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_track_caller_noprof+0x271/0x4e0 mm/slub.c:4395 __do_krealloc mm/slub.c:4957 [inline] krealloc_noprof+0x124/0x340 mm/slub.c:5010 copy_array+0x63/0xf0 kernel/bpf/verifier.c:1392 copy_verifier_state+0xaf/0xf10 kernel/bpf/verifier.c:1742 push_stack+0x19d/0x390 kernel/bpf/verifier.c:2116 check_cond_jmp_op+0x1469/0x2910 kernel/bpf/verifier.c:16780 do_check_insn kernel/bpf/verifier.c:19975 [inline] do_check+0x6751/0xe520 kernel/bpf/verifier.c:20112 do_check_common+0x1949/0x24f0 kernel/bpf/verifier.c:23283 do_check_main kernel/bpf/verifier.c:23366 [inline] bpf_check+0x12c60/0x1d4c0 kernel/bpf/verifier.c:24726 bpf_prog_load+0x1318/0x1930 kernel/bpf/syscall.c:2979 __sys_bpf+0x528/0x870 kernel/bpf/syscall.c:6029 __do_sys_bpf kernel/bpf/syscall.c:6139 [inline] __se_sys_bpf kernel/bpf/syscall.c:6137 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137 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: 0033:0x7fb876d8eba9 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:00007fb874ff6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fb876fd5fa0 RCX: 00007fb876d8eba9 RDX: 0000000000000094 RSI: 0000200000000840 RDI: 0000000000000005 RBP: 00007fb876e11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb876fd6038 R14: 00007fb876fd5fa0 R15: 00007ffe20859488 Allocated by task 6532: 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:393 [inline] bpf_map_area_alloc+0x64/0x180 kernel/bpf/syscall.c:406 prealloc_elems_and_freelist+0x86/0x1d0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x33f/0x4c0 kernel/bpf/stackmap.c:114 map_create+0xaa0/0x14d0 kernel/bpf/syscall.c:1480 __sys_bpf+0x60f/0x870 kernel/bpf/syscall.c:6011 __do_sys_bpf kernel/bpf/syscall.c:6139 [inline] __se_sys_bpf kernel/bpf/syscall.c:6137 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137 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 ffff88804e69a800 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 [ffff88804e69a800, ffff88804e69aa40) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4e698 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888059d73501 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a44b280 ffffea0000c0fc00 dead000000000003 raw: 0000000000000000 0000000000100010 00000000f5000000 ffff888059d73501 head: 00fff00000000040 ffff88801a44b280 ffffea0000c0fc00 dead000000000003 head: 0000000000000000 0000000000100010 00000000f5000000 ffff888059d73501 head: 00fff00000000003 ffffea000139a601 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5622, tgid 5622 (sshd), ts 68911850346, free_ts 66565088947 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_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2492 [inline] allocate_slab+0x8a/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] __do_kmalloc_node mm/slub.c:4375 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4388 kmalloc_noprof include/linux/slab.h:909 [inline] kmalloc_array_noprof include/linux/slab.h:948 [inline] alloc_pipe_info+0x1fd/0x4d0 fs/pipe.c:815 get_pipe_inode fs/pipe.c:894 [inline] create_pipe_files+0x8a/0x7e0 fs/pipe.c:926 __do_pipe_flags+0x46/0x1f0 fs/pipe.c:988 do_pipe2+0x9c/0x170 fs/pipe.c:1036 __do_sys_pipe2 fs/pipe.c:1054 [inline] __se_sys_pipe2 fs/pipe.c:1052 [inline] __x64_sys_pipe2+0x5a/0x70 fs/pipe.c:1052 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 5530 tgid 5530 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 free_large_kmalloc+0x13a/0x1f0 mm/slub.c:4820 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1086 skb_release_all net/core/skbuff.c:1151 [inline] __kfree_skb net/core/skbuff.c:1165 [inline] consume_skb+0x9e/0xf0 net/core/skbuff.c:1397 netlink_recvmsg+0x5b2/0xa30 net/netlink/af_netlink.c:1974 sock_recvmsg_nosec net/socket.c:1065 [inline] sock_recvmsg+0x229/0x270 net/socket.c:1087 ____sys_recvmsg+0x1c9/0x460 net/socket.c:2834 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2876 __sys_recvmsg net/socket.c:2909 [inline] __do_sys_recvmsg net/socket.c:2915 [inline] __se_sys_recvmsg net/socket.c:2912 [inline] __x64_sys_recvmsg+0x198/0x260 net/socket.c:2912 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 Memory state around the buggy address: ffff88804e69a900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88804e69a980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88804e69aa00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff88804e69aa80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804e69ab00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 0f 84 3c 01 00 00 je 0x142 6: 48 85 db test %rbx,%rbx 9: 0f 85 63 01 00 00 jne 0x172 f: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 14: 4c 8b 75 d0 mov -0x30(%rbp),%r14 18: 4c 89 e7 mov %r12,%rdi 1b: e8 df c4 eb 09 call 0x9ebc4ff 20: e8 ea 41 36 00 call 0x36420f 25: fb sti 26: 4c 8b 65 c0 mov -0x40(%rbp),%r12 * 2a: 49 8d bc 24 18 16 00 lea 0x1618(%r12),%rdi <-- trapping instruction 31: 00 32: 48 89 f8 mov %rdi,%rax 35: 48 c1 e8 03 shr $0x3,%rax 39: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 3e: 84 c0 test %al,%al