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BUG: KASAN: slab-out-of-bounds in predicate_parse kernel/trace/trace_events_filter.c:557 [inline]
BUG: KASAN: slab-out-of-bounds in process_preds+0x1958/0x19b0 kernel/trace/trace_events_filter.c:1505
Write of size 4 at addr ffff8801d2cc52f0 by task syzkaller805061/4413

CPU: 1 PID: 4413 Comm: syzkaller805061 Not tainted 4.16.0+ #4
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_store4_noabort+0x17/0x20 mm/kasan/report.c:437
 predicate_parse kernel/trace/trace_events_filter.c:557 [inline]
 process_preds+0x1958/0x19b0 kernel/trace/trace_events_filter.c:1505
 create_filter+0x1a8/0x370 kernel/trace/trace_events_filter.c:1714
 ftrace_profile_set_filter+0x109/0x2b0 kernel/trace/trace_events_filter.c:2042
 perf_event_set_filter+0x248/0x1230 kernel/events/core.c:9064
 _perf_ioctl+0x84c/0x15e0 kernel/events/core.c:5056
 perf_ioctl+0x59/0x80 kernel/events/core.c:5107
 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
 SYSC_ioctl fs/ioctl.c:708 [inline]
 SyS_ioctl+0x24/0x30 fs/ioctl.c:706
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x43fda9
RSP: 002b:00007fffc1641498 EFLAGS: 00000213 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fda9
RDX: 0000000020000100 RSI: 0000000040082406 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000213 R12: 00000000004016d0
R13: 0000000000401760 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 1:
 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]
 kzalloc_node include/linux/slab.h:712 [inline]
 disk_expand_part_tbl+0x236/0x3c0 block/genhd.c:1261
 __alloc_disk_node+0x16f/0x500 block/genhd.c:1444
 nbd_dev_add+0xdc/0x9f0 drivers/block/nbd.c:1449
 nbd_init+0x20e/0x22f drivers/block/nbd.c:2114
 do_one_initcall+0x127/0x913 init/main.c:883
 do_initcall_level init/main.c:951 [inline]
 do_initcalls init/main.c:959 [inline]
 do_basic_setup init/main.c:977 [inline]
 kernel_init_freeable+0x49b/0x58e init/main.c:1127
 kernel_init+0x11/0x1b3 init/main.c:1053
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:411

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8801d2cc5280
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 48 bytes to the right of
 64-byte region [ffff8801d2cc5280, ffff8801d2cc52c0)
The buggy address belongs to the page:
page:ffffea00074b3140 count:1 mapcount:0 mapping:ffff8801d2cc5000 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801d2cc5000 0000000000000000 0000000100000020
raw: ffffea00074c9f60 ffffea00074968e0 ffff8801dac00340 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d2cc5180: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff8801d2cc5200: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
>ffff8801d2cc5280: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
                                                             ^
 ffff8801d2cc5300: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
 ffff8801d2cc5380: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
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