syz-executor4[8330] is installing a program with bpf_probe_write_user helper that may corrupt user memory! ================================================================== BUG: KASAN: use-after-free in predicate_parse kernel/trace/trace_events_filter.c:562 [inline] BUG: KASAN: use-after-free in process_preds+0x1905/0x19d0 kernel/trace/trace_events_filter.c:1508 Read of size 4 at addr ffff8801c06bfff0 by task syz-executor6/8891 CPU: 0 PID: 8891 Comm: syz-executor6 Not tainted 4.17.0-rc4+ #20 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 predicate_parse kernel/trace/trace_events_filter.c:562 [inline] process_preds+0x1905/0x19d0 kernel/trace/trace_events_filter.c:1508 create_filter+0x155/0x270 kernel/trace/trace_events_filter.c:1716 ftrace_profile_set_filter+0x130/0x2e0 kernel/trace/trace_events_filter.c:2041 perf_event_set_filter+0x248/0x1230 kernel/events/core.c:9079 _perf_ioctl+0x84c/0x15e0 kernel/events/core.c:5059 perf_ioctl+0x59/0x80 kernel/events/core.c:5110 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 __do_sys_ioctl fs/ioctl.c:708 [inline] __se_sys_ioctl fs/ioctl.c:706 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a09 RSP: 002b:00007fd04258ec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd04258f6d4 RCX: 0000000000455a09 RDX: 00000000200000c0 RSI: 0000000040082406 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002bf R14: 00000000006f8288 R15: 0000000000000000 The buggy address belongs to the page: page:ffffea000701afc0 count:0 mapcount:-127 mapping:0000000000000000 index:0x0 flags: 0x2fffc0000000000() raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffff80 raw: ffffea00066903a0 ffffea000661f5a0 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c06bfe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8801c06bff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8801c06bff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8801c06c0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801c06c0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================