From: syzbot <syzbot+3a288d5f5530b901310e@syzkaller.appspotmail.com>
To: davem@davemloft.net, edumazet@google.com,
linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
sunlw.fnst@cn.fujitsu.com, syzkaller-bugs@googlegroups.com
Subject: KMSAN: uninit-value in dev_uc_add_excl
Date: Thu, 20 Sep 2018 13:54:05 -0700 [thread overview]
Message-ID: <000000000000368ca9057653b99a@google.com> (raw)
Hello,
syzbot found the following crash on:
HEAD commit: 99e79f6a8963 kmsan: disable assembly implementations of cr..
git tree: https://github.com/google/kmsan.git/master
console output: https://syzkaller.appspot.com/x/log.txt?x=14ccc911400000
kernel config: https://syzkaller.appspot.com/x/.config?x=dc53c800f40430e5
dashboard link: https://syzkaller.appspot.com/bug?extid=3a288d5f5530b901310e
compiler: clang version 8.0.0 (trunk 339414)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=178141fa400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=113d1efa400000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3a288d5f5530b901310e@syzkaller.appspotmail.com
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
==================================================================
BUG: KMSAN: uninit-value in memcmp+0x11d/0x180 lib/string.c:863
CPU: 1 PID: 4318 Comm: syz-executor998 Not tainted 4.19.0-rc3+ #49
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+0x14b/0x190 lib/dump_stack.c:113
kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
__msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
memcmp+0x11d/0x180 lib/string.c:863
dev_uc_add_excl+0x165/0x7b0 net/core/dev_addr_lists.c:464
ndo_dflt_fdb_add net/core/rtnetlink.c:3463 [inline]
rtnl_fdb_add+0x1081/0x1270 net/core/rtnetlink.c:3558
rtnetlink_rcv_msg+0xa0b/0x1530 net/core/rtnetlink.c:4715
netlink_rcv_skb+0x36e/0x5f0 net/netlink/af_netlink.c:2454
rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4733
netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
netlink_unicast+0x1638/0x1720 net/netlink/af_netlink.c:1343
netlink_sendmsg+0x1205/0x1290 net/netlink/af_netlink.c:1908
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg net/socket.c:631 [inline]
___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
__sys_sendmsg net/socket.c:2152 [inline]
__do_sys_sendmsg net/socket.c:2161 [inline]
__se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
__x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440ee9
Code: e8 cc ab 02 00 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 bb 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff6a93b518 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440ee9
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 000000000000b4b0
R13: 0000000000401ec0 R14: 0000000000000000 R15: 0000000000000000
Uninit was created at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
slab_post_alloc_hook mm/slab.h:446 [inline]
slab_alloc_node mm/slub.c:2718 [inline]
__kmalloc_node_track_caller+0x9e7/0x1160 mm/slub.c:4351
__kmalloc_reserve net/core/skbuff.c:138 [inline]
__alloc_skb+0x2f5/0x9e0 net/core/skbuff.c:206
alloc_skb include/linux/skbuff.h:996 [inline]
netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline]
netlink_sendmsg+0xb49/0x1290 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg net/socket.c:631 [inline]
___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
__sys_sendmsg net/socket.c:2152 [inline]
__do_sys_sendmsg net/socket.c:2161 [inline]
__se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
__x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
entry_SYSCALL_64_after_hwframe+0x63/0xe7
==================================================================
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
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reply other threads:[~2018-09-20 20:54 UTC|newest]
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