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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 ffff8801b549bff0 by task syz-executor5/16092

CPU: 1 PID: 16092 Comm: syz-executor5 Not tainted 4.17.0-rc6+ #23
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:00007f5016c83c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5016c846d4 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 15558:
 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
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554
 getname_flags+0xd0/0x5a0 fs/namei.c:140
 user_path_at_empty+0x2d/0x50 fs/namei.c:2555
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x24a/0x7c0 fs/open.c:389
 __do_sys_access fs/open.c:441 [inline]
 __se_sys_access fs/open.c:439 [inline]
 __x64_sys_access+0x59/0x80 fs/open.c:439
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 15558:
 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]
 kmem_cache_free+0x86/0x2d0 mm/slab.c:3756
 putname+0xf2/0x130 fs/namei.c:261
 filename_lookup+0x38b/0x4f0 fs/namei.c:2330
 user_path_at_empty+0x40/0x50 fs/namei.c:2555
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x24a/0x7c0 fs/open.c:389
 __do_sys_access fs/open.c:441 [inline]
 __se_sys_access fs/open.c:439 [inline]
 __x64_sys_access+0x59/0x80 fs/open.c:439
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801b549acc0
 which belongs to the cache names_cache of size 4096
The buggy address is located 816 bytes to the right of
 4096-byte region [ffff8801b549acc0, ffff8801b549bcc0)
The buggy address belongs to the page:
page:ffffea0006d52680 count:1 mapcount:0 mapping:ffff8801b549acc0 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801b549acc0 0000000000000000 0000000100000001
raw: ffffea0006d52620 ffffea0007659a20 ffff8801da988dc0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b549be80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801b549bf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8801b549bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                             ^
 ffff8801b549c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801b549c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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