syzbot


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

Status: fixed on 2020/02/14 01:19
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+9328206518f08318a5fd@syzkaller.appspotmail.com
Fix commit: 04b69426d846 hsr: fix slab-out-of-bounds Read in hsr_debugfs_rename()
First crash: 1631d, last: 1621d
Cause bisection: introduced by (bisect log) :
commit 4c2d5e33dcd3a6333a7895be3b542ff3d373177c
Author: Taehee Yoo <ap420073@gmail.com>
Date: Sun Dec 22 11:26:39 2019 +0000

  hsr: rename debugfs file when interface name is changed

Crash: KASAN: slab-out-of-bounds Read in hsr_debugfs_rename (log)
Repro: C syz .config
  
Discussions (4)
Title Replies (including bot) Last reply
[PATCH 5.4 000/203] 5.4.13-stable review 216 (216) 2020/11/18 21:41
[PATCH AUTOSEL 5.4 06/26] rxrpc: Unlock new call in rxrpc_new_incoming_call() rather than the caller 21 (21) 2020/01/10 22:05
[PATCH net] hsr: fix slab-out-of-bounds Read in hsr_debugfs_rename() 2 (2) 2019/12/31 08:51
KASAN: slab-out-of-bounds Read in hsr_debugfs_rename 0 (2) 2019/12/28 13:11

Sample crash report:
8021q: adding VLAN 0 to HW filter on device batadv0
@: renamed from hsr_slave_0
==================================================================
BUG: KASAN: slab-out-of-bounds in hsr_debugfs_rename+0xa8/0xc0 net/hsr/hsr_debugfs.c:73
Read of size 8 at addr ffff88809f7f4cd8 by task syz-executor679/9217

CPU: 1 PID: 9217 Comm: syz-executor679 Not tainted 5.5.0-rc2-syzkaller #0
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+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 hsr_debugfs_rename+0xa8/0xc0 net/hsr/hsr_debugfs.c:73
 hsr_netdev_notify+0x6c8/0xa00 net/hsr/hsr_main.c:49
 notifier_call_chain+0xc2/0x230 kernel/notifier.c:83
 __raw_notifier_call_chain kernel/notifier.c:361 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:368
 call_netdevice_notifiers_info net/core/dev.c:1893 [inline]
 call_netdevice_notifiers_info+0xba/0x130 net/core/dev.c:1878
 call_netdevice_notifiers_extack net/core/dev.c:1905 [inline]
 call_netdevice_notifiers net/core/dev.c:1919 [inline]
 dev_change_name+0x504/0x930 net/core/dev.c:1270
 do_setlink+0x2d28/0x3720 net/core/rtnetlink.c:2571
 __rtnl_newlink+0xbf0/0x1790 net/core/rtnetlink.c:3238
 rtnl_newlink+0x69/0xa0 net/core/rtnetlink.c:3363
 rtnetlink_rcv_msg+0x45e/0xaf0 net/core/rtnetlink.c:5424
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:659
 ____sys_sendmsg+0x753/0x880 net/socket.c:2330
 ___sys_sendmsg+0x100/0x170 net/socket.c:2384
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4425d9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 6b 0e fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd616ed1b8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004425d9
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 0000000000000003 R08: 00000000bb1414ac R09: 00000000bb1414ac
R10: 00000000bb1414ac R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000403960 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 9217:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527
 __do_kmalloc_node mm/slab.c:3616 [inline]
 __kmalloc_node+0x4e/0x70 mm/slab.c:3623
 kmalloc_node include/linux/slab.h:579 [inline]
 kvmalloc_node+0x68/0x100 mm/util.c:574
 kvmalloc include/linux/mm.h:655 [inline]
 kvzalloc include/linux/mm.h:663 [inline]
 alloc_netdev_mqs+0x98/0xde0 net/core/dev.c:9731
 rtnl_create_link+0x22d/0xab0 net/core/rtnetlink.c:3042
 __rtnl_newlink+0xfa0/0x1790 net/core/rtnetlink.c:3295
 rtnl_newlink+0x69/0xa0 net/core/rtnetlink.c:3363
 rtnetlink_rcv_msg+0x45e/0xaf0 net/core/rtnetlink.c:5424
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:659
 __sys_sendto+0x262/0x380 net/socket.c:1985
 __do_sys_sendto net/socket.c:1997 [inline]
 __se_sys_sendto net/socket.c:1993 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1993
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff88809f7f4000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 3288 bytes inside of
 4096-byte region [ffff88809f7f4000, ffff88809f7f5000)
The buggy address belongs to the page:
page:ffffea00027dfd00 refcount:1 mapcount:0 mapping:ffff8880aa402000 index:0x0 compound_mapcount: 0
raw: 00fffe0000010200 ffffea00028eb488 ffffea0002387b08 ffff8880aa402000
raw: 0000000000000000 ffff88809f7f4000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809f7f4b80: 00 00 00 00 00 00 00 00 07 fc fc fc fc fc fc fc
 ffff88809f7f4c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88809f7f4c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                    ^
 ffff88809f7f4d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88809f7f4d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/27 22:23 bpf 3c2f450e553c be5c2c81 .config console log report syz C ci-upstream-bpf-kasan-gce
2019/12/27 22:46 net-old a5bcd72e054a be5c2c81 .config console log report syz ci-upstream-net-this-kasan-gce
2019/12/27 08:22 net-old a5bcd72e054a be5c2c81 .config console log report syz ci-upstream-net-this-kasan-gce
2019/12/27 06:10 bpf 3c2f450e553c be5c2c81 .config console log report syz ci-upstream-bpf-kasan-gce
2020/01/06 09:08 bpf 3c2f450e553c 438e1227 .config console log report ci-upstream-bpf-kasan-gce
2020/01/06 08:25 bpf 3c2f450e553c 438e1227 .config console log report ci-upstream-bpf-kasan-gce
2020/01/06 08:23 bpf 3c2f450e553c 438e1227 .config console log report ci-upstream-bpf-kasan-gce
2020/01/06 06:26 bpf 3c2f450e553c 438e1227 .config console log report ci-upstream-bpf-kasan-gce
2019/12/29 23:18 bpf 3c2f450e553c af6b8ef8 .config console log report ci-upstream-bpf-kasan-gce
2019/12/29 15:39 bpf 3c2f450e553c af6b8ef8 .config console log report ci-upstream-bpf-kasan-gce
2019/12/29 14:38 bpf 3c2f450e553c af6b8ef8 .config console log report ci-upstream-bpf-kasan-gce
2019/12/28 23:34 bpf 3c2f450e553c af6b8ef8 .config console log report ci-upstream-bpf-kasan-gce
2019/12/28 16:10 bpf 3c2f450e553c af6b8ef8 .config console log report ci-upstream-bpf-kasan-gce
2019/12/28 08:26 bpf 3c2f450e553c be5c2c81 .config console log report ci-upstream-bpf-kasan-gce
2019/12/27 22:48 bpf 3c2f450e553c be5c2c81 .config console log report ci-upstream-bpf-kasan-gce
2019/12/27 19:58 bpf 3c2f450e553c be5c2c81 .config console log report ci-upstream-bpf-kasan-gce
2019/12/27 13:12 bpf 3c2f450e553c be5c2c81 .config console log report ci-upstream-bpf-kasan-gce
2019/12/27 05:27 bpf 3c2f450e553c be5c2c81 .config console log report ci-upstream-bpf-kasan-gce
* Struck through repros no longer work on HEAD.