fix realloc-of-non-malloced pointer, and reduce size while at it

diff --git a/shell/hush.c b/shell/hush.c
index 9af7f51051b495c34925388e17a35981f3f0fdfc..eae0e10f5883197543d94e589df657296e6321b5 100644 (file)
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -423,7 +423,7 @@ static const struct built_in_command bltins[] = {
 static const char *set_cwd(void)
 {
        if (cwd == bb_msg_unknown)
-               cwd = NULL;     /* xrealloc_getcwd_or_warn(arg) called free(arg) */
+               cwd = NULL;     /* xrealloc_getcwd_or_warn(arg) calls free(arg)! */
        cwd = xrealloc_getcwd_or_warn((char *)cwd);
        if (!cwd)
                cwd = bb_msg_unknown;

diff --git a/shell/lash.c b/shell/lash.c
index 5f2dacd18b3cc9f322ca3138667d8ee298013c77..729d102c602ffa0af7ac4333672a2c5130c4016d 100644 (file)
--- a/shell/lash.c
+++ b/shell/lash.c
@@ -153,7 +153,7 @@ static int shell_context;  /* Type prompt trigger (PS1 or PS2) */
 
 
 /* Globals that are static to this file */
-static const char *cwd;
+static char *cwd;
 static char *local_pending_command;
 static struct jobset job_list = { NULL, NULL };
 static int argc;
@@ -207,6 +207,14 @@ So   cmd->text        becomes  child->family->text
      job_list          becomes  child->family->job_list
  */
 
+
+static void update_cwd(void)
+{
+       cwd = xrealloc_getcwd_or_warn(cwd);
+       if (!cwd)
+               cwd = xstrdup(bb_msg_unknown);
+}
+
 /* built-in 'cd <path>' handler */
 static int builtin_cd(struct child_prog *child)
 {
@@ -220,9 +228,7 @@ static int builtin_cd(struct child_prog *child)
                bb_perror_msg("cd: %s", newdir);
                return EXIT_FAILURE;
        }
-       cwd = xrealloc_getcwd_or_warn((char *)cwd);
-       if (!cwd)
-               cwd = bb_msg_unknown;
+       update_cwd();
        return EXIT_SUCCESS;
 }
 
@@ -347,9 +353,7 @@ static int builtin_jobs(struct child_prog *child)
 /* built-in 'pwd' handler */
 static int builtin_pwd(struct child_prog ATTRIBUTE_UNUSED *dummy)
 {
-       cwd = xrealloc_getcwd_or_warn((char *)cwd);
-       if (!cwd)
-               cwd = bb_msg_unknown;
+       update_cwd();
        puts(cwd);
        return EXIT_SUCCESS;
 }
@@ -1452,9 +1456,7 @@ static int busy_loop(FILE * input)
 #if ENABLE_FEATURE_CLEAN_UP
 static void free_memory(void)
 {
-       if (cwd && cwd != bb_msg_unknown) {
-               free((char*)cwd);
-       }
+       free(cwd);
 
        if (job_list.fg && !job_list.fg->running_progs) {
                remove_job(&job_list, job_list.fg);
@@ -1571,14 +1573,12 @@ int lash_main(int argc_l, char **argv_l)
        }
 
        /* initialize the cwd -- this is never freed...*/
-       cwd = xrealloc_getcwd_or_warn(NULL);
-       if (!cwd)
-               cwd = bb_msg_unknown;
+       update_cwd();
 
        if (ENABLE_FEATURE_CLEAN_UP) atexit(free_memory);
 
        if (ENABLE_FEATURE_EDITING) cmdedit_set_initial_prompt();
        else PS1 = NULL;
 
-       return (busy_loop(input));
+       return busy_loop(input);
 }