Add error checking for poorly-formed crossystem args
R=petkov@chromium.org
BUG=chromium-os:13322
TEST=manual
The following command lines should cause crossystem to fail with a
warning about a poorly formed parameter:
crossystem ''
crossystem '=cros_debug'
crossystem '?cros_debug'
The following command line should warn that you can't use both = and ?:
crossystem cros_debug?=0
(that is, it warns, not just compares with '=0')
The following should print 'UNEQUAL'
crossystem cros_debug? || echo UNEQUAL
(because it's comparing cros_debug with an empty string)
Review URL: http://codereview.chromium.org/6718012
Change-Id: I2e2851515f4914b16aba64065600fb92d9ad1a63
(cherry picked from commit f27583f08361522909e49155d8b14671f644ec85)
Review URL: http://codereview.chromium.org/6675014
diff --git a/utility/crossystem_main.c b/utility/crossystem_main.c
index 53166e4..3163438 100644
--- a/utility/crossystem_main.c
+++ b/utility/crossystem_main.c
@@ -99,6 +99,8 @@
* Returns the parameter, or NULL if no match. */
const Param* FindParam(const char* name) {
const Param* p;
+ if (!name)
+ return NULL;
for (p = sys_param_list; p->name; p++) {
if (!strcasecmp(p->name, name))
return p;
@@ -220,22 +222,34 @@
/* Otherwise, loop through params and get/set them */
for (i = 1; i < argc && retval == 0; i++) {
- int has_set = (NULL != strchr(argv[i], '='));
- int has_expect = (NULL != strchr(argv[i], '?'));
+ char* has_set = strchr(argv[i], '=');
+ char* has_expect = strchr(argv[i], '?');
char* name = strtok(argv[i], "=?");
char* value = strtok(NULL, "=?");
- const Param* p = FindParam(name);
- if (!p) {
- fprintf(stderr, "Invalid parameter name: %s\n", name);
+ const Param* p;
+
+ /* Make sure args are well-formed. '' or '=foo' or '?foo' not allowed. */
+ if (!name || has_set == argv[i] || has_expect == argv[i]) {
+ fprintf(stderr, "Poorly formed parameter\n");
PrintHelp(progname);
return 1;
}
+ if (!value)
+ value=""; /* Allow setting/checking an empty string ('foo=' or 'foo?') */
if (has_set && has_expect) {
fprintf(stderr, "Use either = or ? in a parameter, but not both.\n");
PrintHelp(progname);
return 1;
}
+ /* Find the parameter */
+ p = FindParam(name);
+ if (!p) {
+ fprintf(stderr, "Invalid parameter name: %s\n", name);
+ PrintHelp(progname);
+ return 1;
+ }
+
if (i > 1)
printf(" "); /* Output params space-delimited */
if (has_set)
