NFSD: Stricter buffer size checking in fs/nfsd/nfsctl.c

Clean up: For consistency, handle output buffer size checking in a
other nfsctl functions the same way it's done for write_versions().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

1 files changed, 9 insertions, 5 deletions

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index a152694e016e..877e713a0fd6 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -695,8 +695,9 @@ static ssize_t write_threads(struct file *file, char *buf, size_t size)
                 if (rv)
                         return rv;
         }
-        sprintf(buf, "%d\n", nfsd_nrthreads());
-        return strlen(buf);
+
+        return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n",
+                                                        nfsd_nrthreads());
 }
 
 /**
@@ -1197,7 +1198,9 @@ static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
                 nfsd_max_blksize = bsize;
                 mutex_unlock(&nfsd_mutex);
         }
-        return sprintf(buf, "%d\n", nfsd_max_blksize);
+
+        return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n",
+                                                        nfsd_max_blksize);
 }
 
 #ifdef CONFIG_NFSD_V4
@@ -1221,8 +1224,9 @@ static ssize_t __write_leasetime(struct file *file, char *buf, size_t size)
                         return -EINVAL;
                 nfs4_reset_lease(lease);
         }
-        sprintf(buf, "%ld\n", nfs4_lease_time());
-        return strlen(buf);
+
+        return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%ld\n",
+                                                        nfs4_lease_time());
 }
 
 /**