Quote any non-alphanumeric characters other than '_' or '-' when passing

a command to be run via the shell for the -s and -i options.

diff --git a/src/parse_args.c b/src/parse_args.c
index 3fca61347620955004d8fbcd4625e3380f1dd1d5..2623d57359718fba01c7e0efe386773f58f038ff 100644 (file)
--- a/src/parse_args.c
+++ b/src/parse_args.c
@@ -45,8 +45,9 @@
 #ifdef HAVE_UNISTD_H
 # include <unistd.h>
 #endif /* HAVE_UNISTD_H */
-#include <pwd.h>
+#include <ctype.h>
 #include <grp.h>
+#include <pwd.h>
 
 #include <sudo_usage.h>
 #include "sudo.h"
@@ -380,22 +381,38 @@ parse_args(int argc, char **argv, int *nargc, char ***nargv, char ***settingsp,
            memcpy(av + 1, argv, argc * sizeof(char *));
        } else {
            /* shell -c "command" */
-           size_t size;
-           char *src, *dst, *end;
-
-           /* length of the command + NUL terminator */
-           size = (size_t)(argv[argc - 1] - argv[0]) +
-               strlen(argv[argc - 1]) + 1;
+           size_t cmnd_size = 1024;
+           char *cmnd, *src, *dst, **ap;
+
+           cmnd = dst = emalloc(cmnd_size);
+           for (ap = argv; *ap != NULL; ap++) {
+               for (src = *ap; *src != '\0'; src++) {
+                   /* reserve room for an escaped char + space */
+                   if (cmnd_size < (dst - cmnd) + 3) {
+                       char *new_cmnd;
+                       cmnd_size <<= 1;
+                       new_cmnd = erealloc(cmnd, cmnd_size);
+                       dst = new_cmnd + (dst - cmnd);
+                       cmnd = new_cmnd;
+                   }
+                   if (isalnum((unsigned char)*src) || *src == '_' || *src == '-') {
+                       *dst++ = *src;
+                   } else {
+                       /* quote potential meta character */
+                       *dst++ = '\\';
+                       *dst++ = *src;
+                   }
+               }
+               *dst++ = ' ';
+           }
+           if (cmnd != dst)
+               dst--;  /* replace last space with a NUL */
+           *dst = '\0';
 
            ac = 3;
            av = emalloc2(ac + 1, sizeof(char *));
            av[1] = "-c";
-           av[2] = dst = emalloc(size);
-
-           src = argv[0];
-           for (end = src + size - 1; src < end; src++, dst++)
-               *dst = *src == 0 ? ' ' : *src;
-           *dst = '\0';
+           av[2] = cmnd;
        }
        av[0] = (char *)user_details.shell; /* plugin may override shell */
        av[ac] = NULL;