syzbot


KASAN: slab-out-of-bounds Read in shrink_slab

Status: closed as dup on 2018/07/07 16:48
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+59db6e2c8310927c035f@syzkaller.appspotmail.com
First crash: 2128d, last: 2118d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: stack-out-of-bounds Read in timerqueue_add kernel C 4 2114d 2130d
Discussions (1)
Title Replies (including bot) Last reply
KASAN: slab-out-of-bounds Read in shrink_slab 1 (2) 2018/07/07 16:48

Sample crash report:
QAT: Invalid ioctl
QAT: Invalid ioctl
==================================================================
BUG: KASAN: slab-out-of-bounds in __read_once_size include/linux/compiler.h:188 [inline]
BUG: KASAN: slab-out-of-bounds in list_empty include/linux/list.h:203 [inline]
BUG: KASAN: slab-out-of-bounds in shrink_slab_memcg mm/vmscan.c:595 [inline]
BUG: KASAN: slab-out-of-bounds in shrink_slab+0xa04/0xa60 mm/vmscan.c:671
Read of size 8 at addr ffff880197982e18 by task syz-executor6/18390

CPU: 1 PID: 18390 Comm: syz-executor6 Not tainted 4.18.0-rc4-next-20180713+ #7
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+0x1c9/0x2b4 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+0x242/0x30d mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 __read_once_size include/linux/compiler.h:188 [inline]
 list_empty include/linux/list.h:203 [inline]
 shrink_slab_memcg mm/vmscan.c:595 [inline]
 shrink_slab+0xa04/0xa60 mm/vmscan.c:671
 shrink_node+0x429/0x16a0 mm/vmscan.c:2735
 shrink_zones mm/vmscan.c:2964 [inline]
 do_try_to_free_pages+0x3e7/0x1290 mm/vmscan.c:3026
 try_to_free_mem_cgroup_pages+0x49d/0xc90 mm/vmscan.c:3324
 memory_high_write+0x283/0x310 mm/memcontrol.c:5611
 cgroup_file_write+0x31f/0x840 kernel/cgroup/cgroup.c:3502
 kernfs_fop_write+0x2ba/0x480 fs/kernfs/file.c:316
 __vfs_write+0x117/0x9d0 fs/read_write.c:485
 __kernel_write+0x10c/0x370 fs/read_write.c:506
 write_pipe_buf+0x181/0x240 fs/splice.c:798
 splice_from_pipe_feed fs/splice.c:503 [inline]
 __splice_from_pipe+0x38e/0x7c0 fs/splice.c:627
 splice_from_pipe+0x1ea/0x340 fs/splice.c:662
 default_file_splice_write+0x3c/0x90 fs/splice.c:810
 do_splice_from fs/splice.c:852 [inline]
 direct_splice_actor+0x128/0x190 fs/splice.c:1019
 splice_direct_to_actor+0x318/0x8f0 fs/splice.c:974
 do_splice_direct+0x2d4/0x420 fs/splice.c:1062
 do_sendfile+0x62a/0xe20 fs/read_write.c:1440
 __do_sys_sendfile64 fs/read_write.c:1495 [inline]
 __se_sys_sendfile64 fs/read_write.c:1487 [inline]
 __x64_sys_sendfile64+0x15d/0x250 fs/read_write.c:1487
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455ab9
Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007fa35a1ecc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fa35a1ed6d4 RCX: 0000000000455ab9
RDX: 0000000020000040 RSI: 0000000000000014 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c0d79 R14: 00000000004d1380 R15: 0000000000000000

Allocated by task 17954:
 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:2625
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x252/0x7e0 fs/open.c:378
 __do_sys_access fs/open.c:430 [inline]
 __se_sys_access fs/open.c:428 [inline]
 __x64_sys_access+0x59/0x80 fs/open.c:428
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 17954:
 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+0x397/0x510 fs/namei.c:2371
 user_path_at_empty+0x40/0x50 fs/namei.c:2625
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x252/0x7e0 fs/open.c:378
 __do_sys_access fs/open.c:430 [inline]
 __se_sys_access fs/open.c:428 [inline]
 __x64_sys_access+0x59/0x80 fs/open.c:428
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff880197982ec0
 which belongs to the cache names_cache of size 4096
The buggy address is located 168 bytes to the left of
 4096-byte region [ffff880197982ec0, ffff880197983ec0)
The buggy address belongs to the page:
page:ffffea00065e6080 count:1 mapcount:0 mapping:ffff8801da987dc0 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffffea0006516688 ffffea00071ce988 ffff8801da987dc0
raw: 0000000000000000 ffff880197982ec0 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff880197982d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff880197982d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff880197982e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                            ^
 ffff880197982e80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff880197982f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (84):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/16 07:42 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/16 05:14 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/16 03:19 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/16 01:33 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 23:57 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 20:09 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 17:22 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 14:47 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 12:45 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 11:11 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 10:07 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 08:30 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 06:49 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 06:04 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 03:50 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 01:17 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/15 00:16 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 23:01 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 21:42 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 19:02 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 16:13 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 15:01 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 13:54 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 13:45 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 13:27 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 12:38 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 11:59 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 11:31 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 11:09 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 09:04 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 06:02 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 05:27 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 05:23 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 03:11 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 03:03 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 02:36 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 02:34 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 02:15 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 01:19 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/14 01:08 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/13 22:38 linux-next 483d835c8189 92a49505 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/06 17:41 linux-next 526674536360 9636bc93 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.