fs/nfsd/nfs4proc.c:1219:17: warning: 'strncpy' specified bound 63 equals destination size

From: kernel test robot
Date: Tue Jan 18 2022 - 06:15:25 EST


Hi Dai,

FYI, the error/warning still remains.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: e3a8b6a1e70c37702054ae3c7c07ed828435d8ee
commit: f4e44b393389c77958f7c58bf4415032b4cda15b NFSD: delay unmount source's export after inter-server copy completed.
date: 8 months ago
config: parisc-allyesconfig (https://download.01.org/0day-ci/archive/20220118/202201181657.6QL0fpaT-lkp@xxxxxxxxx/config)
compiler: hppa-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f4e44b393389c77958f7c58bf4415032b4cda15b
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout f4e44b393389c77958f7c58bf4415032b4cda15b
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=parisc SHELL=/bin/bash drivers/net/ethernet/mellanox/mlx5/core/esw/ drivers/net/wireless/broadcom/brcm80211/brcmfmac/ drivers/net/wireless/broadcom/brcm80211/brcmsmac/ drivers/net/wireless/intel/iwlwifi/ fs/nfsd/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

fs/nfsd/nfs4proc.c: In function 'nfsd4_ssc_setup_dul.constprop':
>> fs/nfsd/nfs4proc.c:1219:17: warning: 'strncpy' specified bound 63 equals destination size [-Wstringop-truncation]
1219 | strncpy(work->nsui_ipaddr, ipaddr, sizeof(work->nsui_ipaddr));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


vim +/strncpy +1219 fs/nfsd/nfs4proc.c

1174
1175 /*
1176 * setup a work entry in the ssc delayed unmount list.
1177 */
1178 static int nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr,
1179 struct nfsd4_ssc_umount_item **retwork, struct vfsmount **ss_mnt)
1180 {
1181 struct nfsd4_ssc_umount_item *ni = 0;
1182 struct nfsd4_ssc_umount_item *work = NULL;
1183 struct nfsd4_ssc_umount_item *tmp;
1184 DEFINE_WAIT(wait);
1185
1186 *ss_mnt = NULL;
1187 *retwork = NULL;
1188 work = kzalloc(sizeof(*work), GFP_KERNEL);
1189 try_again:
1190 spin_lock(&nn->nfsd_ssc_lock);
1191 list_for_each_entry_safe(ni, tmp, &nn->nfsd_ssc_mount_list, nsui_list) {
1192 if (strncmp(ni->nsui_ipaddr, ipaddr, sizeof(ni->nsui_ipaddr)))
1193 continue;
1194 /* found a match */
1195 if (ni->nsui_busy) {
1196 /* wait - and try again */
1197 prepare_to_wait(&nn->nfsd_ssc_waitq, &wait,
1198 TASK_INTERRUPTIBLE);
1199 spin_unlock(&nn->nfsd_ssc_lock);
1200
1201 /* allow 20secs for mount/unmount for now - revisit */
1202 if (signal_pending(current) ||
1203 (schedule_timeout(20*HZ) == 0)) {
1204 kfree(work);
1205 return nfserr_eagain;
1206 }
1207 finish_wait(&nn->nfsd_ssc_waitq, &wait);
1208 goto try_again;
1209 }
1210 *ss_mnt = ni->nsui_vfsmount;
1211 refcount_inc(&ni->nsui_refcnt);
1212 spin_unlock(&nn->nfsd_ssc_lock);
1213 kfree(work);
1214
1215 /* return vfsmount in ss_mnt */
1216 return 0;
1217 }
1218 if (work) {
> 1219 strncpy(work->nsui_ipaddr, ipaddr, sizeof(work->nsui_ipaddr));
1220 refcount_set(&work->nsui_refcnt, 2);
1221 work->nsui_busy = true;
1222 list_add_tail(&work->nsui_list, &nn->nfsd_ssc_mount_list);
1223 *retwork = work;
1224 }
1225 spin_unlock(&nn->nfsd_ssc_lock);
1226 return 0;
1227 }
1228

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0-DAY CI Kernel Test Service, Intel Corporation
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