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KASAN: use-after-free Write in __xfrm_policy_unlink

Status: fixed on 2019/03/06 07:43
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+9d971dd21eb26567036b@syzkaller.appspotmail.com
Fix commit: 1548bc4e0512 xfrm: policy: delete inexact policies from inexact list on hash rebuild
First crash: 2123d, last: 1895d
▶ ▼ Discussions (4)
Title Replies (including bot) Last reply
[PATCH 04/10] xfrm: policy: delete inexact policies from inexact list on hash rebuild 1 (1) 2019/01/25 07:44
[PATCH ipsec 0/7] xfrm: policy: fix various bugs 16 (16) 2019/01/10 08:09
[Patch net] xfrm: fix reinsert in xfrm_hash_rebuild() 3 (3) 2019/01/05 04:29
KASAN: use-after-free Write in __xfrm_policy_unlink 2 (5) 2018/12/27 10:17
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Write in __xfrm_policy_unlink (2) net 7 1775d 1821d 12/26 fixed on 2019/09/02 04:08

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:704 [inline]
BUG: KASAN: use-after-free in hlist_del_rcu include/linux/rculist.h:455 [inline]
BUG: KASAN: use-after-free in __xfrm_policy_unlink+0x9ec/0xa00 net/xfrm/xfrm_policy.c:2212
Write of size 8 at addr ffff88808ad1d690 by task syz-executor791/8433

CPU: 1 PID: 8433 Comm: syz-executor791 Not tainted 5.0.0-rc2+ #27
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+0x1db/0x2d0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/generic_report.c:140
 __hlist_del include/linux/list.h:704 [inline]
 hlist_del_rcu include/linux/rculist.h:455 [inline]
 __xfrm_policy_unlink+0x9ec/0xa00 net/xfrm/xfrm_policy.c:2212
 xfrm_policy_insert+0x223/0x910 net/xfrm/xfrm_policy.c:1587
 xfrm_add_policy+0x2a1/0x6c0 net/xfrm/xfrm_user.c:1657
 xfrm_user_rcv_msg+0x458/0x8d0 net/xfrm/xfrm_user.c:2663
 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477
 xfrm_netlink_rcv+0x70/0x90 net/xfrm/xfrm_user.c:2671
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x7ec/0x910 net/socket.c:2116
 __sys_sendmsg+0x112/0x270 net/socket.c:2154
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg net/socket.c:2161 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x442549
Code: e8 3c e7 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 9b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffd9092b58 EFLAGS: 00000207 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000442549
RDX: 0000000000000000 RSI: 000000002014f000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000207 R12: 0000000000000030
R13: 000000000000dce1 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 8420:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3609
 kmalloc include/linux/slab.h:545 [inline]
 kzalloc include/linux/slab.h:740 [inline]
 xfrm_policy_alloc+0xfb/0x530 net/xfrm/xfrm_policy.c:383
 xfrm_policy_construct+0x30/0x660 net/xfrm/xfrm_user.c:1599
 xfrm_add_policy+0x20a/0x6c0 net/xfrm/xfrm_user.c:1648
 xfrm_user_rcv_msg+0x458/0x8d0 net/xfrm/xfrm_user.c:2663
 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477
 xfrm_netlink_rcv+0x70/0x90 net/xfrm/xfrm_user.c:2671
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x7ec/0x910 net/socket.c:2116
 __sys_sendmsg+0x112/0x270 net/socket.c:2154
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg net/socket.c:2161 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 9:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466
 __cache_free mm/slab.c:3487 [inline]
 kfree+0xcf/0x230 mm/slab.c:3806
 xfrm_policy_destroy_rcu+0x48/0x60 net/xfrm/xfrm_policy.c:407
 __rcu_reclaim kernel/rcu/rcu.h:240 [inline]
 rcu_do_batch kernel/rcu/tree.c:2452 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline]
 rcu_process_callbacks+0xc4a/0x1680 kernel/rcu/tree.c:2754
 __do_softirq+0x30b/0xb11 kernel/softirq.c:292

The buggy address belongs to the object at ffff88808ad1d680
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 16 bytes inside of
 1024-byte region [ffff88808ad1d680, ffff88808ad1da80)
The buggy address belongs to the page:
page:ffffea00022b4700 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0002912308 ffffea00028f6a88 ffff88812c3f0ac0
raw: 0000000000000000 ffff88808ad1c000 0000000100000007 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808ad1d580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808ad1d600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88808ad1d680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88808ad1d700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808ad1d780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (254):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/01/15 18:41 upstream fe76fc6aaf53 79cb1a7c .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/01/15 18:13 upstream fe76fc6aaf53 79cb1a7c .config console log report syz C ci-upstream-kasan-gce-root
2019/01/15 18:13 upstream fe76fc6aaf53 79cb1a7c .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/01/15 18:11 upstream fe76fc6aaf53 79cb1a7c .config console log report syz C ci-upstream-kasan-gce
2019/01/15 17:00 upstream fe76fc6aaf53 79cb1a7c .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/01/15 16:36 upstream fe76fc6aaf53 79cb1a7c .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/01/14 19:40 upstream 1c7fc5cbc339 95485883 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/01/14 19:36 upstream 1c7fc5cbc339 95485883 .config console log report syz C ci-upstream-kasan-gce-root
2019/01/14 17:09 upstream 1c7fc5cbc339 95485883 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/01/14 17:08 upstream 1c7fc5cbc339 95485883 .config console log report syz C ci-upstream-kasan-gce-root
2019/01/10 06:49 upstream 4064e47c8281 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/01/10 06:49 upstream 4064e47c8281 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce
2019/01/10 06:48 upstream 4064e47c8281 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/01/10 06:48 upstream 4064e47c8281 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce-root
2019/01/09 13:53 upstream a88cc8da0279 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/01/09 13:34 upstream a88cc8da0279 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce
2019/01/09 13:18 upstream a88cc8da0279 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/01/09 13:15 upstream a88cc8da0279 45c0c1b1 .config console log report syz C ci-upstream-kasan-gce-root
2019/01/09 03:35 upstream 7b5585136713 010ed08b .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/01/09 00:59 upstream 7b5585136713 010ed08b .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/01/09 00:52 upstream 7b5585136713 010ed08b .config console log report syz C ci-upstream-kasan-gce
2019/01/09 00:51 upstream 7b5585136713 010ed08b .config console log report syz C ci-upstream-kasan-gce-root
2019/01/06 04:58 upstream f1c2f8857c5a 53be0a37 .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/01/06 04:53 upstream f1c2f8857c5a 53be0a37 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/01/06 04:23 upstream f1c2f8857c5a 53be0a37 .config console log report syz C ci-upstream-kasan-gce
2019/01/06 03:46 upstream f1c2f8857c5a 53be0a37 .config console log report syz C ci-upstream-kasan-gce-root
2019/01/15 17:49 net-old 2f960bd05640 79cb1a7c .config console log report syz C ci-upstream-net-this-kasan-gce
2019/01/14 20:38 net-old 2f960bd05640 95485883 .config console log report syz C ci-upstream-net-this-kasan-gce
2019/01/14 19:15 net-old 2f960bd05640 95485883 .config console log report syz C ci-upstream-net-this-kasan-gce
2019/01/10 06:25 net-old d972f3dce8d1 45c0c1b1 .config console log report syz C ci-upstream-net-this-kasan-gce
2019/01/09 12:54 net-old d972f3dce8d1 45c0c1b1 .config console log report syz C ci-upstream-net-this-kasan-gce
2019/01/09 00:28 net-old 977e4899c9b4 010ed08b .config console log report syz C ci-upstream-net-this-kasan-gce
2019/01/06 04:10 net-old d4a7e9bb74b5 53be0a37 .config console log report syz C ci-upstream-net-this-kasan-gce
2019/01/15 18:11 net-next-old b71acb0e3721 79cb1a7c .config console log report syz C ci-upstream-net-kasan-gce
2019/01/14 19:39 net-next-old b71acb0e3721 95485883 .config console log report syz C ci-upstream-net-kasan-gce
2019/01/10 07:00 net-next-old b71acb0e3721 45c0c1b1 .config console log report syz C ci-upstream-net-kasan-gce
2019/01/09 13:16 net-next-old b71acb0e3721 45c0c1b1 .config console log report syz C ci-upstream-net-kasan-gce
2019/01/09 08:11 net-next-old b71acb0e3721 45c0c1b1 .config console log report syz C ci-upstream-net-kasan-gce
2019/01/06 12:58 net-next-old b71acb0e3721 94f8adb5 .config console log report syz C ci-upstream-net-kasan-gce
2018/12/22 08:04 net-next-old ce28bb445388 603b5124 .config console log report syz C ci-upstream-net-kasan-gce
2019/01/10 08:17 linux-next 6cab33afc3dd 45c0c1b1 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/01/09 13:17 linux-next d6e77253170d 45c0c1b1 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/01/09 02:27 linux-next 139287cc2cc0 010ed08b .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/01/06 13:18 linux-next a4983672f9ca 94f8adb5 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/01/14 16:47 upstream 1c7fc5cbc339 95485883 .config console log report syz ci-upstream-kasan-gce
2019/01/14 17:06 net-next-old b71acb0e3721 95485883 .config console log report syz ci-upstream-net-kasan-gce
2018/12/20 23:03 net-next-old a9cd3439e3c6 aaf59e84 .config console log report syz ci-upstream-net-kasan-gce
2019/03/03 07:51 net-old 07f12b26e21a 1c0e457a .config console log report ci-upstream-net-this-kasan-gce
2019/01/30 05:21 net-old abfd04f738c2 aa432daf .config console log report ci-upstream-net-this-kasan-gce
2019/01/29 23:08 net-old abfd04f738c2 aa432daf .config console log report ci-upstream-net-this-kasan-gce
2019/01/29 09:59 net-old abfd04f738c2 aa432daf .config console log report ci-upstream-net-this-kasan-gce
2019/01/28 19:27 net-old abfd04f738c2 629c2a27 .config console log report ci-upstream-net-this-kasan-gce
2019/01/28 00:51 net-old abfd04f738c2 c73f090a .config console log report ci-upstream-net-this-kasan-gce
2019/01/27 18:27 net-old abfd04f738c2 c73f090a .config console log report ci-upstream-net-this-kasan-gce
2019/01/24 06:13 net-old 63530aba7826 56558f63 .config console log report ci-upstream-net-this-kasan-gce
2019/01/24 01:53 net-old 63530aba7826 56558f63 .config console log report ci-upstream-net-this-kasan-gce
2019/01/23 12:21 net-old ab06418b7fb8 7cf3249c .config console log report ci-upstream-net-this-kasan-gce
2019/01/23 08:22 net-old 56cb4e503499 b1ff06b2 .config console log report ci-upstream-net-this-kasan-gce
2019/01/21 22:20 net-old 49a57857aeea badbbeee .config console log report ci-upstream-net-this-kasan-gce
2019/01/21 09:58 net-old 6436408e814b fd37a550 .config console log report ci-upstream-net-this-kasan-gce
2019/01/17 00:29 net-old f2f98c1d7fa8 d538790b .config console log report ci-upstream-net-this-kasan-gce
2019/01/13 19:54 net-old 8d008e64a2eb c3f3344c .config console log report ci-upstream-net-this-kasan-gce
2019/01/30 03:54 net-next-old 085c4c7dd2b6 aa432daf .config console log report ci-upstream-net-kasan-gce
2019/01/29 19:40 net-next-old 085c4c7dd2b6 aa432daf .config console log report ci-upstream-net-kasan-gce
2019/01/29 18:31 net-next-old 085c4c7dd2b6 aa432daf .config console log report ci-upstream-net-kasan-gce
2019/01/29 07:01 net-next-old 085c4c7dd2b6 aa432daf .config console log report ci-upstream-net-kasan-gce
2019/01/29 03:40 net-next-old 085c4c7dd2b6 aa432daf .config console log report ci-upstream-net-kasan-gce
2019/01/28 13:35 net-next-old 085c4c7dd2b6 629c2a27 .config console log report ci-upstream-net-kasan-gce
2019/01/28 08:44 net-next-old 085c4c7dd2b6 c73f090a .config console log report ci-upstream-net-kasan-gce
2019/01/27 20:27 net-next-old 085c4c7dd2b6 c73f090a .config console log report ci-upstream-net-kasan-gce
2019/01/27 10:58 net-next-old a4b829949326 c73f090a .config console log report ci-upstream-net-kasan-gce
2019/01/27 00:38 net-next-old a4b829949326 c73f090a .config console log report ci-upstream-net-kasan-gce
2019/01/26 20:59 net-next-old f859a4484703 c73f090a .config console log report ci-upstream-net-kasan-gce
2019/01/26 16:39 net-next-old f859a4484703 c73f090a .config console log report ci-upstream-net-kasan-gce
2019/01/26 10:05 net-next-old f859a4484703 c73f090a .config console log report ci-upstream-net-kasan-gce
2019/01/26 07:30 net-next-old 30e5c2c6bf28 ebf7a37c .config console log report ci-upstream-net-kasan-gce
2019/01/26 00:17 net-next-old 30e5c2c6bf28 ebf7a37c .config console log report ci-upstream-net-kasan-gce
2019/01/24 14:52 net-next-old 254764e55652 ce1ccf97 .config console log report ci-upstream-net-kasan-gce
2019/01/23 05:41 net-next-old 1435d9970378 b1ff06b2 .config console log report ci-upstream-net-kasan-gce
2019/01/22 02:17 net-next-old 28f9d1a3d4fe badbbeee .config console log report ci-upstream-net-kasan-gce
2019/01/21 04:31 net-next-old 4e15cbe82996 fd37a550 .config console log report ci-upstream-net-kasan-gce
2019/01/20 22:13 net-next-old 4e15cbe82996 fd37a550 .config console log report ci-upstream-net-kasan-gce
2019/01/20 04:53 net-next-old 133bbb18ab1a 353f32ea .config console log report ci-upstream-net-kasan-gce
2019/01/19 01:58 net-next-old 435f3f267780 2103a236 .config console log report ci-upstream-net-kasan-gce
2019/01/18 11:09 net-next-old 22c2ad616b74 5bf17c30 .config console log report ci-upstream-net-kasan-gce
2019/01/17 09:32 net-next-old bdbe8cc1a30c c2faf9b2 .config console log report ci-upstream-net-kasan-gce
2019/01/17 06:07 net-next-old bdbe8cc1a30c c2faf9b2 .config console log report ci-upstream-net-kasan-gce
2019/01/16 11:39 net-next-old 9dde6da51297 b47fa78d .config console log report ci-upstream-net-kasan-gce
2019/01/16 00:23 net-next-old 7939f8beecf1 79cb1a7c .config console log report ci-upstream-net-kasan-gce
2019/01/15 05:11 net-next-old b71acb0e3721 ebacf5cb .config console log report ci-upstream-net-kasan-gce
2019/01/13 23:41 net-next-old b71acb0e3721 c3f3344c .config console log report ci-upstream-net-kasan-gce
2019/01/13 14:22 net-next-old b71acb0e3721 c3f3344c .config console log report ci-upstream-net-kasan-gce
2018/07/18 02:43 net-next-old fcaccc829382 6d5bd5b5 .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.