================================================================== BUG: KASAN: use-after-free in _copy_to_user+0x9d/0xd0 lib/usercopy.c:27 Read of size 1001 at addr ffff888171bffff2 by task syz-executor.3/6252 CPU: 1 PID: 6252 Comm: syz-executor.3 Not tainted 4.14.139+ #36 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xca/0x134 lib/dump_stack.c:53 print_address_description+0x60/0x226 mm/kasan/report.c:187 __kasan_report.cold+0x1a/0x41 mm/kasan/report.c:316 _copy_to_user+0x9d/0xd0 lib/usercopy.c:27 copy_to_user include/linux/uaccess.h:155 [inline] bpf_test_finish.isra.0+0xa7/0x160 net/bpf/test_run.c:59 bpf_prog_test_run_skb+0x528/0x8c0 net/bpf/test_run.c:144 bpf_prog_test_run kernel/bpf/syscall.c:1346 [inline] SYSC_bpf kernel/bpf/syscall.c:1618 [inline] SyS_bpf+0xa3b/0x3830 kernel/bpf/syscall.c:1563 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459829 RSP: 002b:00007ff822ce6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829 RDX: 0000000000000028 RSI: 00000000200004c0 RDI: 000000000000000a RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff822ce76d4 R13: 00000000004bfb92 R14: 00000000004d1818 R15: 00000000ffffffff The buggy address belongs to the page: page:ffffea0005c6ffc0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x4000000000000000() raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888171bffe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888171bfff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888171bfff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888171c00000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888171c00080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================