fs/9p/v9fs.c (v9fs_parse_options): Handle kstrdup and match_strdup failure. Now that this function can fail, return an int, diagnose other option-parsing failures, and adjust the sole caller: (v9fs_session_init): Handle kstrdup failure. Propagate any new v9fs_parse_options failure "up".

Signed-off-by: Jim Meyering <meyering@redhat.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 34 insertions, 6 deletions

diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index 79d310c00188..5c1ccaf0416c 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -73,16 +73,17 @@ static match_table_t tokens = {
  * v9fs_parse_options - parse mount options into session structure
  * @v9ses: existing v9fs session information
  *
+ * Return 0 upon success, -ERRNO upon failure.
  */
 
-static void v9fs_parse_options(struct v9fs_session_info *v9ses)
+static int v9fs_parse_options(struct v9fs_session_info *v9ses)
 {
         char *options;
         substring_t args[MAX_OPT_ARGS];
         char *p;
         int option = 0;
         char *s, *e;
-        int ret;
+        int ret = 0;
 
         /* setup defaults */
         v9ses->afid = ~0;
@@ -90,19 +91,26 @@ static void v9fs_parse_options(struct v9fs_session_info *v9ses)
         v9ses->cache = 0;
 
         if (!v9ses->options)
-                return;
+                return 0;
 
         options = kstrdup(v9ses->options, GFP_KERNEL);
+        if (!options) {
+                P9_DPRINTK(P9_DEBUG_ERROR,
+                           "failed to allocate copy of option string\n");
+                return -ENOMEM;
+        }
+
         while ((p = strsep(&options, ",")) != NULL) {
                 int token;
                 if (!*p)
                         continue;
                 token = match_token(p, tokens, args);
                 if (token < Opt_uname) {
-                        ret = match_int(&args[0], &option);
-                        if (ret < 0) {
+                        int r = match_int(&args[0], &option);
+                        if (r < 0) {
                                 P9_DPRINTK(P9_DEBUG_ERROR,
                                         "integer field, but no integer?\n");
+                                ret = r;
                                 continue;
                         }
                 }
@@ -138,6 +146,13 @@ static void v9fs_parse_options(struct v9fs_session_info *v9ses)
 
                 case Opt_access:
                         s = match_strdup(&args[0]);
+                        if (!s) {
+                                P9_DPRINTK(P9_DEBUG_ERROR,
+                                           "failed to allocate copy"
+                                           " of option argument\n");
+                                ret = -ENOMEM;
+                                break;
+                        }
                         v9ses->flags &= ~V9FS_ACCESS_MASK;
                         if (strcmp(s, "user") == 0)
                                 v9ses->flags |= V9FS_ACCESS_USER;
@@ -157,6 +172,7 @@ static void v9fs_parse_options(struct v9fs_session_info *v9ses)
                 }
         }
         kfree(options);
+        return ret;
 }
 
 /**
@@ -172,6 +188,7 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 {
         int retval = -EINVAL;
         struct p9_fid *fid;
+        int rc;
 
         v9ses->uname = __getname();
         if (!v9ses->uname)
@@ -190,7 +207,18 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
         v9ses->dfltuid = V9FS_DEFUID;
         v9ses->dfltgid = V9FS_DEFGID;
         v9ses->options = kstrdup(data, GFP_KERNEL);
-        v9fs_parse_options(v9ses);
+        if (!v9ses->options) {
+                P9_DPRINTK(P9_DEBUG_ERROR,
+                           "failed to allocate copy of option string\n");
+                retval = -ENOMEM;
+                goto error;
+        }
+
+        rc = v9fs_parse_options(v9ses);
+        if (rc < 0) {
+                retval = rc;
+                goto error;
+        }
 
         v9ses->clnt = p9_client_create(dev_name, v9ses->options);