NFSD: Full checking of authentication name

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 5 insertions, 9 deletions

diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c
index dc948f667650..e1b3d3d472da 100644
--- a/fs/nfsd/nfs4idmap.c
+++ b/fs/nfsd/nfs4idmap.c
@@ -215,7 +215,8 @@ idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
         memset(&ent, 0, sizeof(ent));
 
         /* Authentication name */
-        if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
+        len = qword_get(&buf, buf1, PAGE_SIZE);
+        if (len <= 0 || len >= IDMAP_NAMESZ)
                 goto out;
         memcpy(ent.authname, buf1, sizeof(ent.authname));
 
@@ -245,12 +246,10 @@ idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
         /* Name */
         error = -EINVAL;
         len = qword_get(&buf, buf1, PAGE_SIZE);
-        if (len < 0)
+        if (len < 0 || len >= IDMAP_NAMESZ)
                 goto out;
         if (len == 0)
                 set_bit(CACHE_NEGATIVE, &ent.h.flags);
-        else if (len >= IDMAP_NAMESZ)
-                goto out;
         else
                 memcpy(ent.name, buf1, sizeof(ent.name));
         error = -ENOMEM;
@@ -259,15 +258,12 @@ idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
                 goto out;
 
         cache_put(&res->h, cd);
-
         error = 0;
 out:
         kfree(buf1);
-
         return error;
 }
 
-
 static struct ent *
 idtoname_lookup(struct cache_detail *cd, struct ent *item)
 {
@@ -381,7 +377,8 @@ nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
         memset(&ent, 0, sizeof(ent));
 
         /* Authentication name */
-        if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
+        len = qword_get(&buf, buf1, PAGE_SIZE);
+        if (len <= 0 || len >= IDMAP_NAMESZ)
                 goto out;
         memcpy(ent.authname, buf1, sizeof(ent.authname));
 
@@ -421,7 +418,6 @@ nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
         error = 0;
 out:
         kfree(buf1);
-
         return (error);
 }