Fix a segfault in lash, hush, and cmdedit. Each of these used

xgetcwd, but did not check the return for a NULL, and then continued
to call strlen on the NULL when the cwd had been removed from under it.
 -Erik


git-svn-id: svn://busybox.net/trunk/busybox@2613 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 7 insertions, 2 deletions

diff --git a/shell/lash.c b/shell/lash.c
index 1d128355c..0129d6c02 100644
--- a/shell/lash.c
+++ b/shell/lash.c
@@ -297,7 +297,8 @@ static int builtin_cd(struct child_prog *child)
                 return EXIT_FAILURE;
         }
         cwd = xgetcwd(cwd);
-
+        if (!cwd)
+                cwd = unknown;
         return EXIT_SUCCESS;
 }
 
@@ -412,6 +413,9 @@ static int builtin_jobs(struct child_prog *child)
 /* built-in 'pwd' handler */
 static int builtin_pwd(struct child_prog *dummy)
 {
+        cwd = xgetcwd(cwd);
+        if (!cwd)
+                cwd = unknown;
         printf( "%s\n", cwd);
         return EXIT_SUCCESS;
 }
@@ -1827,7 +1831,6 @@ void free_memory(void)
 {
         if (cwd) {
                 free(cwd);
-                cwd = NULL;
         }
         if (local_pending_command)
                 free(local_pending_command);
@@ -1919,6 +1922,8 @@ int shell_main(int argc_l, char **argv_l)
 
         /* initialize the cwd -- this is never freed...*/
         cwd = xgetcwd(0);
+        if (!cwd)
+                cwd = unknown;
 
 #ifdef BB_FEATURE_CLEAN_UP
         atexit(free_memory);