Hello, syzbot found the following issue on: HEAD commit: 3db1a3fa Merge tag 'staging-5.11-rc1' of git://git.kernel... git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=121dc937500000 kernel config: https://syzkaller.appspot.com/x/.config?x=2764fc28a92339f9 dashboard link: https://syzkaller.appspot.com/bug?extid=f4708c391121cfc58396 compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16522287500000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1144680f500000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+f4708c391121cfc58396@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: global-out-of-bounds in string_nocheck lib/vsprintf.c:611 [inline] BUG: KASAN: global-out-of-bounds in string+0x39c/0x3d0 lib/vsprintf.c:693 Read of size 1 at addr ffffffff8faea960 by task syz-executor646/8509 CPU: 0 PID: 8509 Comm: syz-executor646 Not tainted 5.10.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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+0x5/0x4c8 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562 string_nocheck lib/vsprintf.c:611 [inline] string+0x39c/0x3d0 lib/vsprintf.c:693 vsnprintf+0x71b/0x14f0 lib/vsprintf.c:2618 snprintf+0xbb/0xf0 lib/vsprintf.c:2751 smc_nl_get_sys_info+0x493/0x880 net/smc/smc_core.c:249 genl_lock_dumpit+0x60/0x90 net/netlink/genetlink.c:623 netlink_dump+0x4b9/0xb70 net/netlink/af_netlink.c:2268 __netlink_dump_start+0x642/0x900 net/netlink/af_netlink.c:2373 genl_family_rcv_msg_dumpit+0x2af/0x310 net/netlink/genetlink.c:686 genl_family_rcv_msg net/netlink/genetlink.c:780 [inline] genl_rcv_msg+0x434/0x580 net/netlink/genetlink.c:800 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 genl_rcv+0x24/0x40 net/netlink/genetlink.c:811 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2336 ___sys_sendmsg+0xf3/0x170 net/socket.c:2390 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2423 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x440299 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 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff4b943e58 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440299 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401aa0 R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the variable: smc_hostname+0x20/0x40 Memory state around the buggy address: ffffffff8faea800: 00 00 f9 f9 f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 ffffffff8faea880: 00 00 f9 f9 f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 >ffffffff8faea900: 00 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 f9 f9 f9 f9 ^ ffffffff8faea980: 04 f9 f9 f9 f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 ffffffff8faeaa00: 00 00 f9 f9 f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 ================================================================== --- This report 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@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
