hush: fix SEGV in % expansion

function                                             old     new   delta
expand_variables                                    2203    2217     +14

diff --git a/shell/hush.c b/shell/hush.c
index fcbd96c4d200d099498978b274d2d5d940a356a8..2ad8ebacbce433623c81f35082440d2a9e9ef9ff 100644 (file)
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -1990,12 +1990,9 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
         * (expansion of right-hand side of assignment == 1-element expand.
         * It will also do no globbing, and thus we must not backslash-quote!) */
 
-       char first_ch, ored_ch;
-       int i;
-       const char *val;
-       char *dyn_val, *p;
+       char ored_ch;
+       char *p;
 
-       dyn_val = NULL;
        ored_ch = 0;
 
        debug_printf_expand("expand_vars_to_list: arg '%s'\n", arg);
@@ -2004,6 +2001,10 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
        debug_print_list("expand_vars_to_list[0]", output, n);
 
        while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) {
+               char first_ch;
+               int i;
+               char *dyn_val = NULL;
+               const char *val = NULL;
 #if ENABLE_HUSH_TICK
                o_string subst_result = NULL_O_STRING;
 #endif
@@ -2021,7 +2022,6 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
                if ((first_ch & 0x7f) != '@')
                        ored_ch |= first_ch;
 
-               val = NULL;
                switch (first_ch & 0x7f) {
                /* Highest bit in first_ch indicates that var is double-quoted */
                case '$': /* pid */
@@ -2194,16 +2194,16 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
                                if (exp_op == '%' || exp_op == '#') {
                                        if (val) {
                                                /* we need to do a pattern match */
-                                               bool zero;
+                                               bool match_at_left;
                                                char *loc;
-                                               scan_t scan = pick_scan(exp_op, *exp_word, &zero);
+                                               scan_t scan = pick_scan(exp_op, *exp_word, &match_at_left);
                                                if (exp_op == *exp_word)        /* ## or %% */
                                                        ++exp_word;
                                                val = dyn_val = xstrdup(val);
-                                               loc = scan(dyn_val, exp_word, zero);
-                                               if (zero)
+                                               loc = scan(dyn_val, exp_word, match_at_left);
+                                               if (match_at_left) /* # or ## */
                                                        val = loc;
-                                               else
+                                               else if (loc) /* % or %% and match was found */
                                                        *loc = '\0';
                                        }
                                } else {
@@ -2263,11 +2263,11 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
                        }
                } /* default: */
                } /* switch (char after <SPECIAL_VAR_SYMBOL>) */
+
                if (val) {
                        o_addQstr(output, val, strlen(val));
                }
                free(dyn_val);
-               dyn_val = NULL;
                /* Do the check to avoid writing to a const string */
                if (*p != SPECIAL_VAR_SYMBOL)
                        *p = SPECIAL_VAR_SYMBOL;

diff --git a/shell/hush_test/hush-arith/arith.right b/shell/hush_test/hush-arith/arith.right
index 8cde0ee53eaca16f69f2cedfafbe58fa3efc10b8..83155fb0304e7068ba8c18ebe5a1a28f3597ab8d 100644 (file)
--- a/shell/hush_test/hush-arith/arith.right
+++ b/shell/hush_test/hush-arith/arith.right
@@ -63,9 +63,9 @@ hush: error in arithmetic
 40 40
 hush: error in arithmetic
 hush: divide by 0
-hush: can't exec 'let': No such file or directory
+hush: can't execute 'let': No such file or directory
 hush: error in arithmetic
-hush: can't exec 'let': No such file or directory
+hush: can't execute 'let': No such file or directory
 abc
 def
 ghi
@@ -135,4 +135,4 @@ hush: error in arithmetic
 42
 42
 42
-hush: can't exec 'a[b[c]d]=e': No such file or directory
+hush: can't execute 'a[b[c]d]=e': No such file or directory

diff --git a/shell/hush_test/hush-vars/var_posix1.right b/shell/hush_test/hush-vars/var_posix1.right
index 47d52a6c2d85ce629b12604e7fb0d7dab878aeb6..e6cba2758f71fa2a809294a35e2bf669f1e61abd 100644 (file)
--- a/shell/hush_test/hush-vars/var_posix1.right
+++ b/shell/hush_test/hush-vars/var_posix1.right
@@ -32,4 +32,5 @@ ababcdc
 ababcdcd
 Empty:
 ababcdcd}_tail
+ababcdcd
 end

diff --git a/shell/hush_test/hush-vars/var_posix1.tests b/shell/hush_test/hush-vars/var_posix1.tests
index 3069360e1539110b0a0b2f31d91a3f49920337c3..c1f64094dfd56696b228acbb17bba6bbe4655f98 100755 (executable)
--- a/shell/hush_test/hush-vars/var_posix1.tests
+++ b/shell/hush_test/hush-vars/var_posix1.tests
@@ -43,5 +43,6 @@ echo ${var%*}
 echo Empty:${var%%*}
 echo ${var#}}_tail
 # UNFIXED BUG: echo ${var#\}}_tail
+echo ${var%\\*}
 
 echo end

diff --git a/shell/match.c b/shell/match.c
index 47038d667132622f7bbc4b91cdcbc4fb1a768f73..a7101ef7e2fab24ad3cc93749e986c0a72da4891 100644 (file)
--- a/shell/match.c
+++ b/shell/match.c
@@ -11,8 +11,6 @@
  * Kenneth Almquist.
  *
  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
- *
- * Original BSD copyright notice is retained at the end of this file.
  */
 #ifdef STANDALONE
 # include <stdbool.h>
@@ -28,7 +26,7 @@
 
 #define pmatch(a, b) !fnmatch((a), (b), 0)
 
-char *scanleft(char *string, char *pattern, bool zero)
+char *scanleft(char *string, char *pattern, bool match_at_left)
 {
        char c;
        char *loc = string;
@@ -38,7 +36,7 @@ char *scanleft(char *string, char *pattern, bool zero)
                const char *s;
 
                c = *loc;
-               if (zero) {
+               if (match_at_left) {
                        *loc = '\0';
                        s = string;
                } else
@@ -55,7 +53,7 @@ char *scanleft(char *string, char *pattern, bool zero)
        return NULL;
 }
 
-char *scanright(char *string, char *pattern, bool zero)
+char *scanright(char *string, char *pattern, bool match_at_left)
 {
        char c;
        char *loc = string + strlen(string);
@@ -65,7 +63,7 @@ char *scanright(char *string, char *pattern, bool zero)
                const char *s;
 
                c = *loc;
-               if (zero) {
+               if (match_at_left) {
                        *loc = '\0';
                        s = string;
                } else
@@ -88,7 +86,7 @@ int main(int argc, char *argv[])
        char *string;
        char *op;
        char *pattern;
-       bool zero;
+       bool match_at_left;
        char *loc;
 
        int i;
@@ -117,15 +115,15 @@ int main(int argc, char *argv[])
                        continue;
                }
                op = string + off;
-               scan = pick_scan(op[0], op[1], &zero);
+               scan = pick_scan(op[0], op[1], &match_at_left);
                pattern = op + 1;
                if (op[0] == op[1])
                        op[1] = '\0', ++pattern;
                op[0] = '\0';
 
-               loc = scan(string, pattern, zero);
+               loc = scan(string, pattern, match_at_left);
 
-               if (zero) {
+               if (match_at_left) {
                        printf("'%s'\n", loc);
                } else {
                        *loc = '\0';

diff --git a/shell/match.h b/shell/match.h
index 3fc4de340c7f53996bad658d6d10b97f6a0ff222..90597ee54ba62955977ab8773e486e54559267f3 100644 (file)
--- a/shell/match.h
+++ b/shell/match.h
@@ -2,12 +2,12 @@
 
 PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
 
-typedef char *(*scan_t)(char *string, char *match, bool zero);
+typedef char *(*scan_t)(char *string, char *match, bool match_at_left);
 
-char *scanleft(char *string, char *match, bool zero);
-char *scanright(char *string, char *match, bool zero);
+char *scanleft(char *string, char *match, bool match_at_left);
+char *scanright(char *string, char *match, bool match_at_left);
 
-static inline scan_t pick_scan(char op1, char op2, bool *zero)
+static inline scan_t pick_scan(char op1, char op2, bool *match_at_left)
 {
        /* #  - scanleft
         * ## - scanright
@@ -15,10 +15,10 @@ static inline scan_t pick_scan(char op1, char op2, bool *zero)
         * %% - scanleft
         */
        if (op1 == '#') {
-               *zero = true;
+               *match_at_left = true;
                return op1 == op2 ? scanright : scanleft;
        } else {
-               *zero = false;
+               *match_at_left = false;
                return op1 == op2 ? scanleft : scanright;
        }
 }