smc: fix out of bound access in smc_nl_get_sys_info()

mainline inclusion
from mainline-v5.11-rc4
commit 25fe2c9c
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I78IFM
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=25fe2c9c4cd2e97c5f5b69f3aefe69aad3057936



--------------------------------

smc_clc_get_hostname() sets the host pointer to a buffer
which is not NULL-terminated (see smc_clc_init()).

Reported-by:  <syzbot+f4708c391121cfc58396@syzkaller.appspotmail.com>
Fixes: 099b990b ("net/smc: Add support for obtaining system information")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Yingyu Zeng <zengyingyu@sangfor.com.cn>