================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 96 at addr ffff88811272e790 by task syz.5.967/4039 CPU: 1 PID: 4039 Comm: syz.5.967 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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_a448e89f4c9ad9d1+0x28/0x42 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x51f/0x5e0 kernel/events/core.c:10273 __perf_event_overflow+0x437/0x620 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/0x4f0 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+0xffb/0x1050 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:fault_in_readable+0xd5/0x150 mm/gup.c:1915 Code: b1 34 c7 ff 4d 89 f4 49 81 cc ff 0f 00 00 4d 89 f7 49 01 dc 49 81 e4 00 f0 ff ff 4d 39 e6 77 3d e8 90 34 c7 ff 4d 39 e7 74 40 <41> 8a 07 88 45 df 49 81 c7 00 10 00 00 4d 39 e7 74 07 e8 74 34 c7 RSP: 0018:ffffc900062b7a28 EFLAGS: 00050287 RAX: ffffffff81aa46f0 RBX: 0000000000001000 RCX: ffff88810d411440 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900062b7a50 R08: ffff88810d411440 R09: 0000000000000002 R10: 0000000000000006 R11: 0000000000000000 R12: 0000200000185000 R13: dffffc0000000000 R14: 0000200000184000 R15: 0000200000184000 fault_in_iov_iter_readable+0xc3/0x320 lib/iov_iter.c:356 generic_perform_write+0x212/0x740 mm/filemap.c:3904 __generic_file_write_iter+0x17a/0x230 mm/filemap.c:4013 generic_file_write_iter+0xae/0x310 mm/filemap.c:4042 call_write_iter include/linux/fs.h:2282 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x603/0xce0 fs/read_write.c:584 ksys_write+0x149/0x250 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 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: 0033:0x7fec5919ce59 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:00007fec59f86028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fec59416090 RCX: 00007fec5919ce59 RDX: 00000000002a979d RSI: 0000200000000000 RDI: 000000000000000f RBP: 00007fec59232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fec59416128 R14: 00007fec59416090 R15: 00007fff888a87b8 Allocated by task 4040: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x25/0x30 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+0x3a7/0x530 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x49c/0xd80 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 ffff88811272e780 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88811272e780, ffff88811272e7c0) The buggy address belongs to the physical page: page:ffffea000449cb80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11272e flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000001 ffff888100042780 raw: 0000000000000000 0000000000200020 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 1952, tgid 1941 (syz.0.427), ts 76413737016, free_ts 69661231766 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+0x2d12/0x2d80 mm/page_alloc.c:4585 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5929 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc_node_track_caller+0xa0/0x1e0 mm/slab_common.c:958 __do_krealloc mm/slab_common.c:1341 [inline] krealloc+0x6f/0x110 mm/slab_common.c:1374 push_jmp_history kernel/bpf/verifier.c:2462 [inline] is_state_visited kernel/bpf/verifier.c:12321 [inline] do_check+0x2d42/0xf070 kernel/bpf/verifier.c:12461 do_check_common+0x11ae/0x1950 kernel/bpf/verifier.c:14940 do_check_main kernel/bpf/verifier.c:15003 [inline] bpf_check+0x3f98/0x10d10 kernel/bpf/verifier.c:15580 bpf_prog_load+0x10f0/0x16a0 kernel/bpf/syscall.c:2624 __sys_bpf+0x57b/0x850 kernel/bpf/syscall.c:5006 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+0x7f8/0x800 mm/page_alloc.c:3620 free_unref_page+0x95/0x540 mm/page_alloc.c:3718 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6019 __free_slab+0xca/0x1a0 mm/slub.c:2044 free_slab mm/slub.c:2059 [inline] discard_slab+0x29/0x40 mm/slub.c:2065 __slab_free+0x201/0x280 mm/slub.c:3625 do_slab_free mm/slub.c:3666 [inline] ___cache_free+0xbf/0xd0 mm/slub.c:3722 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:311 kasan_slab_alloc include/linux/kasan.h:202 [inline] slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768 slab_alloc_node mm/slub.c:3382 [inline] slab_alloc mm/slub.c:3392 [inline] __kmem_cache_alloc_lru mm/slub.c:3399 [inline] kmem_cache_alloc_lru+0x104/0x280 mm/slub.c:3415 __d_alloc+0x34/0x6c0 fs/dcache.c:1774 d_alloc_pseudo+0x1d/0x70 fs/dcache.c:1906 alloc_file_pseudo+0xe0/0x200 fs/file_table.c:265 __anon_inode_getfile fs/anon_inodes.c:122 [inline] anon_inode_getfile+0xa6/0x180 fs/anon_inodes.c:160 Memory state around the buggy address: ffff88811272e680: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88811272e700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88811272e780: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88811272e800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88811272e880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 34 c7 xor $0xc7,%al 2: ff 4d 89 decl -0x77(%rbp) 5: f4 hlt 6: 49 81 cc ff 0f 00 00 or $0xfff,%r12 d: 4d 89 f7 mov %r14,%r15 10: 49 01 dc add %rbx,%r12 13: 49 81 e4 00 f0 ff ff and $0xfffffffffffff000,%r12 1a: 4d 39 e6 cmp %r12,%r14 1d: 77 3d ja 0x5c 1f: e8 90 34 c7 ff call 0xffc734b4 24: 4d 39 e7 cmp %r12,%r15 27: 74 40 je 0x69 * 29: 41 8a 07 mov (%r15),%al <-- trapping instruction 2c: 88 45 df mov %al,-0x21(%rbp) 2f: 49 81 c7 00 10 00 00 add $0x1000,%r15 36: 4d 39 e7 cmp %r12,%r15 39: 74 07 je 0x42 3b: e8 .byte 0xe8 3c: 74 34 je 0x72 3e: c7 .byte 0xc7