================================================================== BUG: KASAN: use-after-free in _copy_to_user+0xa4/0xd0 lib/usercopy.c:27 Read of size 924 at addr ffff8881f6bffff3 by task syz-executor.2/29755 CPU: 0 PID: 29755 Comm: syz-executor.2 Not tainted 4.14.135 #31 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x19c lib/dump_stack.c:53 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x123/0x190 mm/kasan/kasan.c:267 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272 _copy_to_user+0xa4/0xd0 lib/usercopy.c:27 copy_to_user include/linux/uaccess.h:155 [inline] bpf_test_finish.isra.0+0xaf/0x150 net/bpf/test_run.c:59 bpf_prog_test_run_skb+0x5af/0x9a0 net/bpf/test_run.c:144 bpf_prog_test_run kernel/bpf/syscall.c:1258 [inline] SYSC_bpf kernel/bpf/syscall.c:1520 [inline] SyS_bpf+0x749/0x38f3 kernel/bpf/syscall.c:1469 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459829 RSP: 002b:00007f90bae5fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829 RDX: 0000000000000028 RSI: 0000000020000140 RDI: 000000000000000a RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f90bae606d4 R13: 00000000004bfb92 R14: 00000000004d1758 R15: 00000000ffffffff The buggy address belongs to the page: page:ffffea0007daffc0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x6fffc0000000000() raw: 06fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff raw: ffffea0007daffe0 ffffea0007daffe0 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881f6bffe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881f6bfff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8881f6bfff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881f6c00000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881f6c00080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================