1 files changed, 16 insertions, 6 deletions

diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 08c5fba6db84..b0022cf4efbb 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -572,22 +572,32 @@ int line_config(struct line *lines, unsigned int num, char *str,
 {
         struct line *line;
         char *new;
-        int n;
+        char *end;
+        int n, err;
 
         if (*str == '=') {
                 *error_out = "Can't configure all devices from mconsole";
                 return -EINVAL;
         }
 
-        new = kstrdup(str, GFP_KERNEL);
+        n = simple_strtoul(str, &end, 0);
+        if (*end++ != '=') {
+                *error_out = "Couldn't parse device number";
+                return -EINVAL;
+        }
+        if (n >= num) {
+                *error_out = "Device number out of range";
+                return -EINVAL;
+        }
+
+        new = kstrdup(end, GFP_KERNEL);
         if (new == NULL) {
                 *error_out = "Failed to allocate memory";
                 return -ENOMEM;
         }
-        n = line_setup(lines, num, new, error_out);
-        if (n < 0)
-                return n;
-
+        err = setup_one_line(lines, n, new, INIT_ONE, error_out);
+        if (err)
+                return err;
         line = &lines[n];
         return parse_chan_pair(line->init_str, line, n, opts, error_out);
 }