2 files changed, 47 insertions, 38 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 0890f0977..d1f674e9d 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -904,30 +904,20 @@ static char **xx_add_string_to_strings(int lineno, char **strings, char *add)
         xx_add_string_to_strings(__LINE__, strings, add)
 #endif
 
-static int unset_local_var(const char *name);
-
-static void free_strings_and_unset(char **strings, int unset)
+static void free_strings(char **strings)
 {
         char **v;
 
         if (!strings)
                 return;
-
         v = strings;
         while (*v) {
-                if (unset) {
-                        unset_local_var(*v);
-                }
-                free(*v++);
+                free(*v);
+                v++;
         }
         free(strings);
 }
 
-static void free_strings(char **strings)
-{
-        free_strings_and_unset(strings, 0);
-}
-
 
 /* Helpers for setting new $n and restoring them back
  */
@@ -1340,25 +1330,21 @@ static int set_local_var(char *str, int flg_export, int flg_read_only)
         return 0;
 }
 
-static int unset_local_var(const char *name)
+static int unset_local_var_len(const char *name, int name_len)
 {
         struct variable *cur;
-        struct variable *prev = prev; /* for gcc */
-        int name_len;
+        struct variable **var_pp;
 
         if (!name)
                 return EXIT_SUCCESS;
-        name_len = strlen(name);
-        cur = G.top_var;
-        while (cur) {
+        var_pp = &G.top_var;
+        while ((cur = *var_pp) != NULL) {
                 if (strncmp(cur->varstr, name, name_len) == 0 && cur->varstr[name_len] == '=') {
                         if (cur->flg_read_only) {
                                 bb_error_msg("%s: readonly variable", name);
                                 return EXIT_FAILURE;
                         }
-                        /* prev is ok to use here because 1st variable, HUSH_VERSION,
-                         * is ro, and we cannot reach this code on the 1st pass */
-                        prev->next = cur->next;
+                        *var_pp = cur->next;
                         debug_printf_env("%s: unsetenv '%s'\n", __func__, cur->varstr);
                         bb_unsetenv(cur->varstr);
                         if (name_len == 3 && cur->varstr[0] == 'P' && cur->varstr[1] == 'S')
@@ -1368,12 +1354,31 @@ static int unset_local_var(const char *name)
                         free(cur);
                         return EXIT_SUCCESS;
                 }
-                prev = cur;
-                cur = cur->next;
+                var_pp = &cur->next;
         }
         return EXIT_SUCCESS;
 }
 
+static int unset_local_var(const char *name)
+{
+        return unset_local_var_len(name, strlen(name));
+}
+
+static void unset_vars(char **strings)
+{
+        char **v;
+
+        if (!strings)
+                return;
+        v = strings;
+        while (*v) {
+                const char *eq = strchrnul(*v, '=');
+                unset_local_var_len(*v, (int)(eq - *v));
+                v++;
+        }
+        free(strings);
+}
+
 #if ENABLE_SH_MATH_SUPPORT
 #define is_name(c)      ((c) == '_' || isalpha((unsigned char)(c)))
 #define is_in_name(c)   ((c) == '_' || isalnum((unsigned char)(c)))
@@ -1411,13 +1416,17 @@ static void add_vars(struct variable *var)
                 next = var->next;
                 var->next = G.top_var;
                 G.top_var = var;
-                if (var->flg_export)
+                if (var->flg_export) {
+                        debug_printf_env("%s: restoring exported '%s'\n", __func__, var->varstr);
                         putenv(var->varstr);
+                } else {
+                        debug_printf_env("%s: restoring local '%s'\n", __func__, var->varstr);
+                }
                 var = next;
         }
 }
 
-static struct variable *set_vars_all_and_save_old(char **strings)
+static struct variable *set_vars_and_save_old(char **strings)
 {
         char **s;
         struct variable *old = NULL;
@@ -1438,6 +1447,7 @@ static struct variable *set_vars_all_and_save_old(char **strings)
                         if (var_pp) {
                                 /* Remove variable from global linked list */
                                 var_p = *var_pp;
+                                debug_printf_env("%s: removing '%s'\n", __func__, var_p->varstr);
                                 *var_pp = var_p->next;
                                 /* Add it to returned list */
                                 var_p->next = old;
@@ -3021,13 +3031,13 @@ static void pseudo_exec_argv(nommu_save_t *nommu_save,
 
         new_env = expand_assignments(argv, assignment_cnt);
 #if BB_MMU
-        set_vars_all_and_save_old(new_env);
+        set_vars_and_save_old(new_env);
         free(new_env); /* optional */
-        /* we can also destroy set_vars_all_and_save_old's return value,
+        /* we can also destroy set_vars_and_save_old's return value,
          * to save memory */
 #else
         nommu_save->new_env = new_env;
-        nommu_save->old_vars = set_vars_all_and_save_old(new_env);
+        nommu_save->old_vars = set_vars_and_save_old(new_env);
 #endif
         if (argv_expanded) {
                 argv = argv_expanded;
@@ -3554,7 +3564,7 @@ static int run_pipe(struct pipe *pi)
                         rcode = setup_redirects(command, squirrel);
                         if (rcode == 0) {
                                 new_env = expand_assignments(argv, command->assignment_cnt);
-                                old_vars = set_vars_all_and_save_old(new_env);
+                                old_vars = set_vars_and_save_old(new_env);
                                 if (!funcp) {
                                         debug_printf_exec(": builtin '%s' '%s'...\n",
                                                 x->cmd, argv_expanded[1]);
@@ -3573,7 +3583,7 @@ static int run_pipe(struct pipe *pi)
  clean_up_and_ret:
 #endif
                         restore_redirects(squirrel);
-                        free_strings_and_unset(new_env, 1);
+                        unset_vars(new_env);
                         add_vars(old_vars);
  clean_up_and_ret1:
                         free(argv_expanded);
@@ -3589,7 +3599,7 @@ static int run_pipe(struct pipe *pi)
                         rcode = setup_redirects(command, squirrel);
                         if (rcode == 0) {
                                 new_env = expand_assignments(argv, command->assignment_cnt);
-                                old_vars = set_vars_all_and_save_old(new_env);
+                                old_vars = set_vars_and_save_old(new_env);
                                 debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
                                         argv_expanded[0], argv_expanded[1]);
                                 rcode = run_nofork_applet(i, argv_expanded);
@@ -3687,7 +3697,7 @@ static int run_pipe(struct pipe *pi)
                 /* Clean up after vforked child */
                 free(nommu_save.argv);
                 free(nommu_save.argv_from_re_execing);
-                free_strings_and_unset(nommu_save.new_env, 1);
+                unset_vars(nommu_save.new_env);
                 add_vars(nommu_save.old_vars);
 #endif
                 free(argv_expanded);
diff --git a/shell/hush_test/hush-z_slow/leak_all1.tests b/shell/hush_test/hush-z_slow/leak_all1.tests
index 4e3c4fdec..f8207cf04 100755
--- a/shell/hush_test/hush-z_slow/leak_all1.tests
+++ b/shell/hush_test/hush-z_slow/leak_all1.tests
@@ -64,7 +64,7 @@ HERE
     trap "echo trap$i" WINCH
     f() { true; true; true; true; true; true; true; true; }
     f() { true; true; true; true; true; true; true; true; echo $1; }
-    f >/dev/null
+    i=iii$i t=ttt$i z=zzz$i f >/dev/null
     : $((i++))
 done
 unset i l t
@@ -132,7 +132,7 @@ HERE
     trap "echo trap$i" WINCH
     f() { true; true; true; true; true; true; true; true; }
     f() { true; true; true; true; true; true; true; true; echo $1; }
-    f >/dev/null
+    i=iii$i t=ttt$i z=zzz$i f >/dev/null
     : $((i++))
 done
 unset i l t
@@ -141,9 +141,8 @@ unset -f f
 
 memleak
 kb=$?
-# Observed some variability, bumped to 12k
-if test $kb -le 12; then
+if test $kb -le 4; then
     echo Ok #$kb
 else
-    echo "Bad: $kb kb (or more) leaked"
+    echo "Bad: $kb kb leaked"
 fi