================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x868/0xcf0 kernel/bpf/stackmap.c:265 Write of size 8 at addr ffff8880281d7258 by task syz.3.2040/13887 CPU: 1 UID: 0 PID: 13887 Comm: syz.3.2040 Not tainted 6.17.0-rc1-syzkaller-ge4414b01c1cd #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+0x868/0xcf0 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:1332 [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+0x284/0x4b0 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:4866 free_func_state kernel/bpf/verifier.c:1666 [inline] free_verifier_state+0xaf/0x230 kernel/bpf/verifier.c:1682 pop_stack kernel/bpf/verifier.c:2075 [inline] do_check+0x98c9/0xe520 kernel/bpf/verifier.c:20134 do_check_common+0x1949/0x24f0 kernel/bpf/verifier.c:23260 do_check_main kernel/bpf/verifier.c:23343 [inline] bpf_check+0x1746a/0x1d2d0 kernel/bpf/verifier.c:24703 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: 0033:0x7fcb51b8ebe9 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:00007fcb52a5f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fcb51db5fa0 RCX: 00007fcb51b8ebe9 RDX: 0000000000000048 RSI: 00002000000017c0 RDI: 0000000000000005 RBP: 00007fcb51c11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcb51db6038 R14: 00007fcb51db5fa0 R15: 00007ffe115df918 Allocated by task 13887: 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:4365 [inline] __kmalloc_node_noprof+0x276/0x4e0 mm/slub.c:4371 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 ffff8880281d7000 which belongs to the cache kmalloc-cg-1k of size 1024 The buggy address is located 24 bytes to the right of allocated 576-byte region [ffff8880281d7000, ffff8880281d7240) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x281d0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff8880766b2e01 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a44b280 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080100010 00000000f5000000 ffff8880766b2e01 head: 00fff00000000040 ffff88801a44b280 0000000000000000 dead000000000001 head: 0000000000000000 0000000080100010 00000000f5000000 ffff8880766b2e01 head: 00fff00000000003 ffffea0000a07401 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 5528, tgid 5528 (dhcpcd), ts 65735150666, free_ts 60992140715 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:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4384 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:600 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:669 alloc_skb include/linux/skbuff.h:1336 [inline] alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6665 sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2980 unix_dgram_sendmsg+0x461/0x1850 net/unix/af_unix.c:2153 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 sock_write_iter+0x258/0x330 net/socket.c:1179 do_iter_readv_writev+0x619/0x8b0 fs/read_write.c:-1 vfs_writev+0x31a/0x960 fs/read_write.c:1057 page last free pid 5528 tgid 5528 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:2753 [inline] __put_partials+0x156/0x1a0 mm/slub.c:3218 put_cpu_partial+0x17c/0x250 mm/slub.c:3293 __slab_free+0x2d5/0x3c0 mm/slub.c:4550 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:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4281 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659 alloc_skb include/linux/skbuff.h:1336 [inline] alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6665 sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2980 unix_dgram_sendmsg+0x461/0x1850 net/unix/af_unix.c:2153 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 sock_write_iter+0x258/0x330 net/socket.c:1179 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 Memory state around the buggy address: ffff8880281d7100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880281d7180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880281d7200: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff8880281d7280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880281d7300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc 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