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KASAN: slab-out-of-bounds Read in ip6_xmit

Status: fixed on 2018/03/06 13:29
Subsystems: net
[Documentation on labels]
Fix commit: c113187d38ff tls: Use correct sk->sk_prot for IPV6
First crash: 2456d, last: 2406d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in ip6_xmit (3) net C 69 2285d 2327d 8/28 fixed on 2018/07/09 18:05
android-44 KASAN: slab-out-of-bounds Read in ip6_xmit C 404 2228d 2004d 0/2 public: reported C repro on 2019/04/11 08:44
android-49 KASAN: slab-out-of-bounds Read in ip6_xmit C 388 2228d 2003d 0/3 public: reported C repro on 2019/04/12 00:00
upstream KASAN: slab-out-of-bounds Read in ip6_xmit (2) net C 259 2390d 2404d 4/28 fixed on 2018/03/23 18:14

Sample crash report:
IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready
8021q: adding VLAN 0 to HW filter on device bond0
IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
==================================================================
BUG: KASAN: slab-out-of-bounds in ip6_dst_idev include/net/ip6_fib.h:192 [inline]
BUG: KASAN: slab-out-of-bounds in ip6_xmit+0x1f76/0x2260 net/ipv6/ip6_output.c:264
Read of size 8 at addr ffff8801afb31118 by task syzkaller265383/4225

CPU: 0 PID: 4225 Comm: syzkaller265383 Not tainted 4.16.0-rc3+ #335
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23b/0x360 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 ip6_dst_idev include/net/ip6_fib.h:192 [inline]
 ip6_xmit+0x1f76/0x2260 net/ipv6/ip6_output.c:264
 inet6_csk_xmit+0x2fc/0x580 net/ipv6/inet6_connection_sock.c:139
 l2tp_xmit_core net/l2tp/l2tp_core.c:1096 [inline]
 l2tp_xmit_skb+0x105f/0x1410 net/l2tp/l2tp_core.c:1191
 pppol2tp_sendmsg+0x470/0x670 net/l2tp/l2tp_ppp.c:341
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:640
 SYSC_sendto+0x361/0x5c0 net/socket.c:1747
 SyS_sendto+0x40/0x50 net/socket.c:1715
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4417b9
RSP: 002b:00007ffe9afdbf38 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000000001a RCX: 00000000004417b9
RDX: 0000000000000000 RSI: 0000000020de7000 RDI: 0000000000000004
RBP: 00000000004a3a6e R08: 0000000020000000 R09: 0000000000000000
R10: c3fe68eda9554f8b R11: 0000000000000216 R12: 00007ffe9afdc010
R13: 0000000000402540 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 0:
(stack is not available)

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8801afb31100
 which belongs to the cache ip_dst_cache of size 168
The buggy address is located 24 bytes inside of
 168-byte region [ffff8801afb31100, ffff8801afb311a8)
The buggy address belongs to the page:
page:ffffea0006becc40 count:1 mapcount:0 mapping:ffff8801afb31000 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801afb31000 0000000000000000 0000000100000010
raw: ffff8801d6fd2c48 ffff8801d6fd2c48 ffff8801d8342840 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801afb31000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801afb31080: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff8801afb31100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                            ^
 ffff8801afb31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801afb31200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (156):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/03/02 03:10 upstream 8da5db7ddae1 2c6f473e .config console log report syz C ci-upstream-kasan-gce
2018/01/14 06:48 upstream 2c1cfa499018 c9e7aeae .config console log report syz C ci-upstream-kasan-gce
2018/01/25 18:27 upstream 5b7d27967dab 6b2a715e .config console log report syz C ci-upstream-kasan-gce-386
2018/03/02 02:55 net-next-old f1c02cfb7b30 2c6f473e .config console log report syz C ci-upstream-net-kasan-gce
2018/01/24 21:02 net-next-old 969ade4086b9 866f1102 .config console log report syz C ci-upstream-net-kasan-gce
2018/01/14 06:27 net-next-old 6bd39bc3da0f c9e7aeae .config console log report syz C ci-upstream-net-kasan-gce
2018/01/18 02:58 linux-next 1fec57a31e56 b8970f31 .config console log report syz C ci-upstream-next-kasan-gce
2018/01/18 02:53 mmots ce3c209f6733 b8970f31 .config console log report syz C ci-upstream-mmots-kasan-gce
2018/01/14 06:55 mmots ce3c209f6733 c9e7aeae .config console log report syz C ci-upstream-mmots-kasan-gce
2018/03/05 08:43 upstream e64b9562ba28 2c6f473e .config console log report ci-upstream-kasan-gce
2018/01/29 17:04 upstream d8a5b80568a9 08d47756 .config console log report ci-upstream-kasan-gce
2018/01/27 20:10 upstream c4e0ca7fa241 08146b1a .config console log report ci-upstream-kasan-gce
2018/01/22 02:48 upstream 5515114211c5 fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 12:10 upstream d517bb79f499 fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 11:21 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 11:09 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 10:55 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 10:43 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 10:27 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 10:22 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 09:16 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 09:13 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 08:47 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/21 08:44 upstream 24b61240471a fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/20 12:28 upstream 8dd903d2cf7b fbbdcd92 .config console log report ci-upstream-kasan-gce
2018/01/19 19:40 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 19:08 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 19:07 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 19:00 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 18:50 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 18:48 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 18:47 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 18:42 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 18:14 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 18:00 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 17:55 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/19 17:48 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/18 19:56 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce
2018/01/18 17:54 upstream 1d966eb4d632 56cc113a .config console log report ci-upstream-kasan-gce
2018/01/18 17:02 upstream 1d966eb4d632 56cc113a .config console log report ci-upstream-kasan-gce
2018/01/18 16:54 upstream 1d966eb4d632 56cc113a .config console log report ci-upstream-kasan-gce
2018/01/18 10:08 upstream 1d966eb4d632 56cc113a .config console log report ci-upstream-kasan-gce
2018/03/02 19:21 upstream 5d60e057d127 2c6f473e .config console log report ci-upstream-kasan-gce-386
2018/02/09 16:56 upstream f1517df8701c 9fb5ec43 .config console log report ci-upstream-kasan-gce-386
2018/02/03 23:49 upstream 23c35f48f5fb 632a8c2c .config console log report ci-upstream-kasan-gce-386
2018/01/28 08:40 upstream c4e0ca7fa241 08d47756 .config console log report ci-upstream-kasan-gce-386
2018/01/26 20:41 upstream 993ca2068b04 1d18b112 .config console log report ci-upstream-kasan-gce-386
2018/01/23 06:18 upstream a0ec1ded22e6 228e3d95 .config console log report ci-upstream-kasan-gce-386
2018/01/19 17:41 upstream dda3e15231b3 161c1d64 .config console log report ci-upstream-kasan-gce-386
2018/01/24 11:24 net-next-old 43df215d99e6 a5b7566c .config console log report ci-upstream-net-kasan-gce
2018/01/21 16:56 net-next-old ea9722e2650d fbbdcd92 .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.