================================================================== BUG: KASAN: slab-out-of-bounds in stack_map_get_build_id_offset+0x833/0x9b0 kernel/bpf/stackmap.c:147 Write of size 4 at addr ffff888120f66b30 by task syz-executor184/306 CPU: 1 PID: 306 Comm: syz-executor184 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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 __asan_report_store4_noabort+0x17/0x20 mm/kasan/report_generic.c:355 stack_map_get_build_id_offset+0x833/0x9b0 kernel/bpf/stackmap.c:147 __bpf_get_stackid+0x5ac/0x960 kernel/bpf/stackmap.c:250 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x2ee/0x400 kernel/bpf/stackmap.c:334 bpf_prog_2414a5d5030ea31b+0x21/0x25 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 kernel/events/core.c:9531 [inline] perf_swevent_event+0x243/0x440 kernel/events/core.c:9582 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:copy_user_short_string+0x24/0x40 arch/x86/lib/copy_user_64.S:243 Code: 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 89 d1 8a 06 <88> 07 48 ff c6 48 ff c7 ff c9 75 f2 31 c0 0f 01 ca c3 8d 14 ca eb RSP: 0018:ffffc90000df6e98 EFLAGS: 00050206 RAX: ffffffff82692d30 RBX: 0000000000000003 RCX: 0000000000000003 RDX: 0000000000000003 RSI: ffff88810f90c66c RDI: 000000000000cf3d RBP: ffffc90000df6ec0 R08: ffff88810f90c66e R09: 1ffff11021f218cd R10: dffffc0000000000 R11: ffffed1021f218ce R12: 00007fffffffeffd R13: 0000000000000003 R14: 000000000000cf3d R15: ffff88810f90c66c copy_to_user include/linux/uaccess.h:169 [inline] bpf_verifier_vlog+0x179/0x390 kernel/bpf/log.c:34 verbose+0x1f0/0x2b0 kernel/bpf/verifier.c:303 print_insn_state+0x132/0x1c0 kernel/bpf/verifier.c:930 do_check+0x4127/0xf140 kernel/bpf/verifier.c:12501 do_check_common+0x11c3/0x1970 kernel/bpf/verifier.c:14940 do_check_main kernel/bpf/verifier.c:15003 [inline] bpf_check+0xa04e/0x10e90 kernel/bpf/verifier.c:15580 bpf_prog_load+0x10f4/0x1670 kernel/bpf/syscall.c:2624 __sys_bpf+0x57b/0x850 kernel/bpf/syscall.c:5006 __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 RIP: 0033:0x7f46ef269949 Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffcced482a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f46ef269949 RDX: 0000000000000024 RSI: 0000200000000440 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000006 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f46ef2fcc40 R15: 0000000000000002 Allocated by task 306: 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 ffff888120f66800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 816 bytes inside of 1024-byte region [ffff888120f66800, ffff888120f66c00) The buggy address belongs to the physical page: page:ffffea000483d800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x120f60 head:ffffea000483d800 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100043080 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 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 301, tgid 301 (sshd-session), ts 25208418869, free_ts 25208025883 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931 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 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc_node_track_caller+0xa1/0x1e0 mm/slab_common.c:958 kmalloc_reserve net/core/skbuff.c:449 [inline] __alloc_skb+0x226/0x4a0 net/core/skbuff.c:518 alloc_skb_fclone include/linux/skbuff.h:1372 [inline] tcp_stream_alloc_skb+0x47/0x360 net/ipv4/tcp.c:871 tcp_sendmsg_locked+0xcb7/0x39f0 net/ipv4/tcp.c:1334 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1492 inet_sendmsg+0xb6/0xd0 net/ipv4/af_inet.c:841 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] sock_write_iter+0x2ea/0x3f0 net/socket.c:1134 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1581 [inline] free_pcp_prepare mm/page_alloc.c:1655 [inline] free_unref_page_prepare+0x81b/0x820 mm/page_alloc.c:3622 free_unref_page+0x93/0x530 mm/page_alloc.c:3720 free_the_page mm/page_alloc.c:863 [inline] free_compound_page+0x99/0xd0 mm/page_alloc.c:886 destroy_large_folio+0x68/0xa0 mm/page_alloc.c:923 __folio_put_large mm/swap.c:113 [inline] __folio_put+0xd1/0xe0 mm/swap.c:121 folio_put include/linux/mm.h:1442 [inline] put_page include/linux/mm.h:1494 [inline] page_to_skb+0x4e1/0xb50 drivers/net/virtio_net.c:565 receive_mergeable drivers/net/virtio_net.c:1158 [inline] receive_buf+0x469/0x4890 drivers/net/virtio_net.c:1297 virtnet_receive drivers/net/virtio_net.c:1592 [inline] virtnet_poll+0x5c9/0x1150 drivers/net/virtio_net.c:1710 __napi_poll+0xcd/0x5d0 net/core/dev.c:6644 napi_poll net/core/dev.c:6711 [inline] net_rx_action+0x4a3/0xa90 net/core/dev.c:6825 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642 __do_softirq kernel/softirq.c:680 [inline] invoke_softirq kernel/softirq.c:497 [inline] __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:729 irq_exit_rcu+0x9/0x10 kernel/softirq.c:741 common_interrupt+0xbe/0xe0 arch/x86/kernel/irq.c:242 asm_common_interrupt+0x27/0x40 arch/x86/include/asm/idtentry.h:682 Memory state around the buggy address: ffff888120f66a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888120f66a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888120f66b00: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ^ ffff888120f66b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888120f66c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== syz-executor184 (306) used greatest stack depth: 21664 bytes left ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 89 d1 mov %edx,%ecx 8: 83 e2 07 and $0x7,%edx b: c1 e9 03 shr $0x3,%ecx e: 74 12 je 0x22 10: 4c 8b 06 mov (%rsi),%r8 13: 4c 89 07 mov %r8,(%rdi) 16: 48 8d 76 08 lea 0x8(%rsi),%rsi 1a: 48 8d 7f 08 lea 0x8(%rdi),%rdi 1e: ff c9 dec %ecx 20: 75 ee jne 0x10 22: 21 d2 and %edx,%edx 24: 74 10 je 0x36 26: 89 d1 mov %edx,%ecx 28: 8a 06 mov (%rsi),%al * 2a: 88 07 mov %al,(%rdi) <-- trapping instruction 2c: 48 ff c6 inc %rsi 2f: 48 ff c7 inc %rdi 32: ff c9 dec %ecx 34: 75 f2 jne 0x28 36: 31 c0 xor %eax,%eax 38: 0f 01 ca clac 3b: c3 ret 3c: 8d 14 ca lea (%rdx,%rcx,8),%edx 3f: eb .byte 0xeb