================================================================== BUG: KASAN: slab-out-of-bounds in predicate_parse kernel/trace/trace_events_filter.c:562 [inline] BUG: KASAN: slab-out-of-bounds in process_preds+0x1905/0x19d0 kernel/trace/trace_events_filter.c:1508 Read of size 4 at addr ffff8801d08a3ff0 by task syz-executor1/9796 CPU: 1 PID: 9796 Comm: syz-executor1 Not tainted 4.17.0-rc4+ #17 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:00007fa896d08c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa896d096d4 RCX: 0000000000455a09 RDX: 0000000020000040 RSI: 0000000040082406 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002bf R14: 00000000006f8288 R15: 0000000000000000 Allocated by task 2388: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node+0x47/0x70 mm/slab.c:3689 kmalloc_node include/linux/slab.h:554 [inline] kvmalloc_node+0x6b/0x100 mm/util.c:421 kvmalloc include/linux/mm.h:550 [inline] seq_buf_alloc fs/seq_file.c:32 [inline] seq_read+0xa33/0x1520 fs/seq_file.c:211 kernfs_fop_read+0x13e/0x690 fs/kernfs/file.c:252 __vfs_read+0x10f/0xa50 fs/read_write.c:416 vfs_read+0x17f/0x3d0 fs/read_write.c:452 ksys_read+0xf9/0x250 fs/read_write.c:578 __do_sys_read fs/read_write.c:588 [inline] __se_sys_read fs/read_write.c:586 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:586 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 2388: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 kvfree+0x61/0x70 mm/util.c:440 seq_release+0x51/0x80 fs/seq_file.c:371 kernfs_fop_release+0xf7/0x1a0 fs/kernfs/file.c:781 __fput+0x34d/0x890 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x1e4/0x290 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x2bd/0x310 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801d08a2b40 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 1200 bytes to the right of 4096-byte region [ffff8801d08a2b40, ffff8801d08a3b40) The buggy address belongs to the page: page:ffffea0007422880 count:1 mapcount:0 mapping:ffff8801d08a2b40 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801d08a2b40 0000000000000000 0000000100000001 raw: ffffea00074169a0 ffffea00066a03a0 ffff8801da800dc0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d08a3e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801d08a3f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801d08a3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801d08a4000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801d08a4080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================