KASAN: use-after-free Read in check

KASAN: use-after-free Read in check_lifetime
Status: moderation: reported on 2021/01/06 01:30
Reported-by: syzbot+afd3cfdc74d9898db581@syzkaller.appspotmail.com
First crash: 23d, last: 23d

Sample crash report:

==================================================================
BUG: KASAN: use-after-free in check_lifetime+0x89c/0x9b0 net/ipv4/devinet.c:713
Read of size 4 at addr ffff8880129ee348 by task kworker/0:6/12509

CPU: 0 PID: 12509 Comm: kworker/0:6 Not tainted 5.10.0-next-20201223-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_power_efficient check_lifetime
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:396 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413
 check_lifetime+0x89c/0x9b0 net/ipv4/devinet.c:713
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Allocated by task 4898:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:404 [inline]
 ____kasan_kmalloc mm/kasan/common.c:435 [inline]
 ____kasan_kmalloc.constprop.0+0xa0/0xd0 mm/kasan/common.c:407
 kmalloc include/linux/slab.h:552 [inline]
 kernfs_get_open_node fs/kernfs/file.c:571 [inline]
 kernfs_fop_open+0x957/0xd40 fs/kernfs/file.c:717
 do_dentry_open+0x4b9/0x11b0 fs/open.c:817
 do_open fs/namei.c:3254 [inline]
 path_openat+0x1b9a/0x2730 fs/namei.c:3371
 do_filp_open+0x17e/0x3c0 fs/namei.c:3398
 do_sys_openat2+0x16d/0x420 fs/open.c:1172
 do_sys_open fs/open.c:1188 [inline]
 __do_sys_open fs/open.c:1196 [inline]
 __se_sys_open fs/open.c:1192 [inline]
 __x64_sys_open+0x119/0x1c0 fs/open.c:1192
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff8880129ee300
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 72 bytes inside of
 128-byte region [ffff8880129ee300, ffff8880129ee380)
The buggy address belongs to the page:
page:00000000cee6b9a4 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880129ee300 pfn:0x129ee
flags: 0xfff00000000200(slab)
raw: 00fff00000000200 ffffea0000628308 ffffea00009f1208 ffff888010041640
raw: ffff8880129ee300 000000000010000e 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880129ee200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc
 ffff8880129ee280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880129ee300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff8880129ee380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880129ee400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Maintainers
ci-upstream-linux-next-kasan-gce-root	2021/01/02 01:20	linux-next	d7a03a44	79264ae3	.config	log	report			info	davem@davemloft.net, kuba@kernel.org, kuznet@ms2.inr.ac.ru, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, yoshfuji@linux-ipv6.org