================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 80 at addr ffff8881188b6d90 by task syz.0.2886/8930 CPU: 1 PID: 8930 Comm: syz.0.2886 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x3d0/0x5e0 kernel/events/core.c:10238 __perf_event_overflow+0x437/0x620 kernel/events/core.c:9448 perf_swevent_overflow kernel/events/core.c:9524 [inline] perf_swevent_event+0x2f7/0x530 kernel/events/core.c:-1 do_perf_sw_event kernel/events/core.c:9665 [inline] ___perf_sw_event+0x3bf/0x4f0 kernel/events/core.c:9696 __perf_sw_event+0x134/0x270 kernel/events/core.c:9708 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:__put_user_nocheck_4+0x3/0x11 Code: 00 00 48 39 d9 73 54 0f 01 cb 66 89 01 31 c9 0f 01 ca c3 90 90 90 90 90 48 bb fd ef ff ff ff 7f 00 00 48 39 d9 73 34 0f 01 cb <89> 01 31 c9 0f 01 ca c3 90 90 90 90 90 90 48 bb f9 ef ff ff ff 7f RSP: 0018:ffffc900075c7798 EFLAGS: 00050297 RAX: 0000000000000000 RBX: 00007fffffffeffd RCX: 0000000000000000 RDX: ffffc9000169a000 RSI: 000000000000001b RDI: 00000000ffffffff RBP: ffffc900075c7850 R08: ffff88811fd2d100 R09: 0000000000000002 R10: 0000000000000005 R11: 0000000000000002 R12: 1ffff92000eb8ef8 R13: 0000000000000000 R14: ffff88813243b2d8 R15: 0000000000000000 sock_do_ioctl+0x114/0x330 net/socket.c:1191 sock_ioctl+0x4bd/0x710 net/socket.c:1310 vfs_ioctl fs/ioctl.c:51 [inline] do_vfs_ioctl+0xbc3/0x1cd0 fs/ioctl.c:830 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl+0x9f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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: 0033:0x7f34d939c819 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:00007f34da2c8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f34d9615fa0 RCX: 00007f34d939c819 RDX: 0000000000000000 RSI: 000000000000541b RDI: 0000000000000009 RBP: 00007f34d9432c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f34d9616038 R14: 00007f34d9615fa0 R15: 00007fffb8082ce8 Allocated by task 8930: 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:4987 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5107 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 ffff8881188b6d80 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff8881188b6d80, ffff8881188b6dc0) The buggy address belongs to the physical page: page:ffffea0004622d80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1188b6 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004833b40 dead000000000002 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 107, tgid 107 (udevd), ts 4702743062, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670 prep_new_page+0x1c/0x110 mm/page_alloc.c:2677 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5924 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+0xa1/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x28a/0x460 mm/util.c:592 kvmalloc include/linux/slab.h:716 [inline] simple_xattr_alloc+0x43/0xa0 fs/xattr.c:1008 shmem_initxattrs+0x8d/0x1e0 mm/shmem.c:3294 security_inode_init_security+0x2a9/0x3d0 security/security.c:1133 shmem_mknod+0xbb/0x1d0 mm/shmem.c:2951 shmem_create+0x2c/0x40 mm/shmem.c:3010 page_owner free stack trace missing Memory state around the buggy address: ffff8881188b6c80: 00 00 00 00 00 00 00 03 fc fc fc fc fc fc fc fc ffff8881188b6d00: 00 00 00 00 00 00 00 03 fc fc fc fc fc fc fc fc >ffff8881188b6d80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881188b6e00: 00 00 00 00 00 00 00 03 fc fc fc fc fc fc fc fc ffff8881188b6e80: 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 48 39 d9 cmp %rbx,%rcx 5: 73 54 jae 0x5b 7: 0f 01 cb stac a: 66 89 01 mov %ax,(%rcx) d: 31 c9 xor %ecx,%ecx f: 0f 01 ca clac 12: c3 ret 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 48 bb fd ef ff ff ff movabs $0x7fffffffeffd,%rbx 1f: 7f 00 00 22: 48 39 d9 cmp %rbx,%rcx 25: 73 34 jae 0x5b 27: 0f 01 cb stac * 2a: 89 01 mov %eax,(%rcx) <-- trapping instruction 2c: 31 c9 xor %ecx,%ecx 2e: 0f 01 ca clac 31: c3 ret 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 48 rex.W 39: bb f9 ef ff ff mov $0xffffeff9,%ebx 3e: ff (bad) 3f: 7f .byte 0x7f