bootconfig: Allocate xbc_data inside xbc_init()

Allocate 'xbc_data' in the xbc_init() so that it does
not need to care about the ownership of the copied
data.

Link: https://lkml.kernel.org/r/163177339986.682366.898762699429769117.stgit@devnote2
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h
index 537e1b9..62e09b7 100644 (file)
--- a/include/linux/bootconfig.h
+++ b/include/linux/bootconfig.h
@@ -271,7 +271,7 @@ static inline int __init xbc_node_compose_key(struct xbc_node *node,
 }
 
 /* XBC node initializer */
-int __init xbc_init(char *buf, const char **emsg, int *epos);
+int __init xbc_init(const char *buf, size_t size, const char **emsg, int *epos);
 
 
 /* XBC cleanup data structures */

diff --git a/init/main.c b/init/main.c
index 81a79a7..d894989 100644 (file)
--- a/init/main.c
+++ b/init/main.c
@@ -409,7 +409,7 @@ static void __init setup_boot_config(void)
        const char *msg;
        int pos;
        u32 size, csum;
-       char *data, *copy, *err;
+       char *data, *err;
        int ret;
 
        /* Cut out the bootconfig data even if we have no bootconfig option */
@@ -442,16 +442,7 @@ static void __init setup_boot_config(void)
                return;
        }
 
-       copy = memblock_alloc(size + 1, SMP_CACHE_BYTES);
-       if (!copy) {
-               pr_err("Failed to allocate memory for bootconfig\n");
-               return;
-       }
-
-       memcpy(copy, data, size);
-       copy[size] = '\0';
-
-       ret = xbc_init(copy, &msg, &pos);
+       ret = xbc_init(data, size, &msg, &pos);
        if (ret < 0) {
                if (pos < 0)
                        pr_err("Failed to init bootconfig: %s.\n", msg);

diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 5ae248b..66b02fd 100644 (file)
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -789,6 +789,7 @@ static int __init xbc_verify_tree(void)
  */
 void __init xbc_destroy_all(void)
 {
+       memblock_free_ptr(xbc_data, xbc_data_size);
        xbc_data = NULL;
        xbc_data_size = 0;
        xbc_node_num = 0;
@@ -799,19 +800,20 @@ void __init xbc_destroy_all(void)
 
 /**
  * xbc_init() - Parse given XBC file and build XBC internal tree
- * @buf: boot config text
+ * @data: The boot config text original data
+ * @size: The size of @data
  * @emsg: A pointer of const char * to store the error message
  * @epos: A pointer of int to store the error position
  *
- * This parses the boot config text in @buf. @buf must be a
- * null terminated string and smaller than XBC_DATA_MAX.
+ * This parses the boot config text in @data. @size must be smaller
+ * than XBC_DATA_MAX.
  * Return the number of stored nodes (>0) if succeeded, or -errno
  * if there is any error.
  * In error cases, @emsg will be updated with an error message and
  * @epos will be updated with the error position which is the byte offset
  * of @buf. If the error is not a parser error, @epos will be -1.
  */
-int __init xbc_init(char *buf, const char **emsg, int *epos)
+int __init xbc_init(const char *data, size_t size, const char **emsg, int *epos)
 {
        char *p, *q;
        int ret, c;
@@ -824,28 +826,35 @@ int __init xbc_init(char *buf, const char **emsg, int *epos)
                        *emsg = "Bootconfig is already initialized";
                return -EBUSY;
        }
-
-       ret = strlen(buf);
-       if (ret > XBC_DATA_MAX - 1 || ret == 0) {
+       if (size > XBC_DATA_MAX || size == 0) {
                if (emsg)
-                       *emsg = ret ? "Config data is too big" :
+                       *emsg = size ? "Config data is too big" :
                                "Config data is empty";
                return -ERANGE;
        }
 
+       xbc_data = memblock_alloc(size + 1, SMP_CACHE_BYTES);
+       if (!xbc_data) {
+               if (emsg)
+                       *emsg = "Failed to allocate bootconfig data";
+               return -ENOMEM;
+       }
+       memcpy(xbc_data, data, size);
+       xbc_data[size] = '\0';
+       xbc_data_size = size + 1;
+
        xbc_nodes = memblock_alloc(sizeof(struct xbc_node) * XBC_NODE_MAX,
                                   SMP_CACHE_BYTES);
        if (!xbc_nodes) {
                if (emsg)
                        *emsg = "Failed to allocate bootconfig nodes";
+               xbc_destroy_all();
                return -ENOMEM;
        }
        memset(xbc_nodes, 0, sizeof(struct xbc_node) * XBC_NODE_MAX);
-       xbc_data = buf;
-       xbc_data_size = ret + 1;
-       last_parent = NULL;
 
-       p = buf;
+       last_parent = NULL;
+       p = xbc_data;
        do {
                q = strpbrk(p, "{}=+;:\n#");
                if (!q) {

diff --git a/tools/bootconfig/main.c b/tools/bootconfig/main.c
index fd67496..7269c9e 100644 (file)
--- a/tools/bootconfig/main.c
+++ b/tools/bootconfig/main.c
@@ -229,7 +229,7 @@ static int load_xbc_from_initrd(int fd, char **buf)
                return -EINVAL;
        }
 
-       ret = xbc_init(*buf, &msg, NULL);
+       ret = xbc_init(*buf, size, &msg, NULL);
        /* Wrong data */
        if (ret < 0) {
                pr_err("parse error: %s.\n", msg);
@@ -269,7 +269,7 @@ static int init_xbc_with_error(char *buf, int len)
        if (!copy)
                return -ENOMEM;
 
-       ret = xbc_init(buf, &msg, &pos);
+       ret = xbc_init(buf, len, &msg, &pos);
        if (ret < 0)
                show_xbc_error(copy, msg, pos);
        free(copy);
@@ -382,7 +382,7 @@ static int apply_xbc(const char *path, const char *xbc_path)
        memcpy(data, buf, size);
 
        /* Check the data format */
-       ret = xbc_init(buf, &msg, &pos);
+       ret = xbc_init(buf, size, &msg, &pos);
        if (ret < 0) {
                show_xbc_error(data, msg, pos);
                free(data);