fs/9p: detect invalid options as much as possible

Currently when detecting invalid options in option parsing, some
options(e.g.  msize) just set errno and allow to continuously validate
other options so that it can detect invalid options as much as possible
and give proper error messages together.

This patch applies same rule to option 'cache' and 'access' when
detecting -EINVAL.

Link: http://lkml.kernel.org/r/1525340676-34072-2-git-send-email-cgxu519@gmx.com
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/9p/v9fs.c

@@ -210,12 +210,12 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 				p9_debug(P9_DEBUG_ERROR,
 					 "integer field, but no integer?\n");
 				ret = r;
-				continue;
-			}
-			v9ses->debug = option;
+			} else {
+				v9ses->debug = option;
 #ifdef CONFIG_NET_9P_DEBUG
-			p9_debug_level = option;
+				p9_debug_level = option;
 #endif
+			}
 			break;
 
 		case Opt_dfltuid:
@@ -231,7 +231,6 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 				p9_debug(P9_DEBUG_ERROR,
 					 "uid field, but not a uid?\n");
 				ret = -EINVAL;
-				continue;
 			}
 			break;
 		case Opt_dfltgid:
@@ -247,7 +246,6 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 				p9_debug(P9_DEBUG_ERROR,
 					 "gid field, but not a gid?\n");
 				ret = -EINVAL;
-				continue;
 			}
 			break;
 		case Opt_afid:
@@ -256,9 +254,9 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 				p9_debug(P9_DEBUG_ERROR,
 					 "integer field, but no integer?\n");
 				ret = r;
-				continue;
+			} else {
+				v9ses->afid = option;
 			}
-			v9ses->afid = option;
 			break;
 		case Opt_uname:
 			kfree(v9ses->uname);
@@ -306,13 +304,12 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 					 "problem allocating copy of cache arg\n");
 				goto free_and_return;
 			}
-			ret = get_cache_mode(s);
-			if (ret == -EINVAL) {
-				kfree(s);
-				goto free_and_return;
-			}
+			r = get_cache_mode(s);
+			if (r < 0)
+				ret = r;
+			else
+				v9ses->cache = r;
 
-			v9ses->cache = ret;
 			kfree(s);
 			break;
 
@@ -341,14 +338,12 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 					pr_info("Unknown access argument %s\n",
 						s);
 					kfree(s);
-					goto free_and_return;
+					continue;
 				}
 				v9ses->uid = make_kuid(current_user_ns(), uid);
 				if (!uid_valid(v9ses->uid)) {
 					ret = -EINVAL;
 					pr_info("Uknown uid %s\n", s);
-					kfree(s);
-					goto free_and_return;
 				}
 			}