sof-logger: ensure NULL string is not passed to printf/fprintf

Due to allocation failures, or invalid content in dictionary,
"params" entries in "struct proc_ldc_entry" may be NULL.

In print_entry_params(), the NULL entries may be passed
as arguments to fprintf(). While e.g. glibc handles these without
error, this is not guaranteed behaviour and may result in segfault
on some platforms.

Fix the issue by aborting program if allocation fails and
explicitly handling the cases when asprintf_entry_text returns
NULL.

Signed-off-by: Kai Vehmanen <[email protected]>
(cherry picked from commit 1a7a36a)

tools/logger/convert.c

@@ -65,6 +65,8 @@ static const char *BAD_PTR_STR = "<bad uid ptr 0x%.8x>";
 #define UUID_LOWER "%s%s%s<%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x>%s%s%s"
 #define UUID_UPPER "%s%s%s<%08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X>%s%s%s"
 
+static const char *missing = "<missing>";
+
 static int read_entry_from_ldc_file(struct ldc_entry *entry, uint32_t log_entry_address);
 
 char *format_uid_raw(const struct sof_uuid_entry *uid_entry, int use_colors, int name_first,
@@ -249,6 +251,8 @@ static void process_params(struct proc_ldc_entry *pe,
 			/* check for string printing, because it leads to logger crash */
 			log_err("String printing is not supported\n");
 			pe->params[i] = (uintptr_t)log_asprintf("<String @ 0x%08x>", raw_param);
+			if (!pe->params[i])
+				abort();
 			pe->subst_mask |= 1 << i;
 			++i;
 			p += 2;
@@ -257,6 +261,8 @@ static void process_params(struct proc_ldc_entry *pe,
 			/* substitute UUID entry address with formatted string pointer from heap */
 			pe->params[i] = (uintptr_t)asprintf_uuid(p, raw_param, use_colors,
 								 &uuid_fmt_len);
+			if (!pe->params[i])
+				abort();
 			pe->subst_mask |= 1 << i;
 			++i;
 			/* replace uuid formatter with %s */
@@ -268,7 +274,12 @@ static void process_params(struct proc_ldc_entry *pe,
 			/* %pQ format specifier */
 			/* substitute log entry address with formatted entry text */
 			pe->params[i] = (uintptr_t)asprintf_entry_text(raw_param);
-			pe->subst_mask |= 1 << i;
+
+			if (pe->params[i])
+				pe->subst_mask |= 1 << i;
+			else
+				pe->params[i] = (uintptr_t)missing;
+
 			++i;
 
 			/* replace entry formatter with %s */
@@ -1021,7 +1032,7 @@ static int dump_ldc_info(void)
 	while (remaining > 0) {
 		name = format_uid_raw(&uid_ptr[cnt], 0, 0, false, false);
 		uid_addr = get_uuid_key(&uid_ptr[cnt]);
-		fprintf(out_fd, "\t%p  %s\n", (void *)uid_addr, name);
+		fprintf(out_fd, "\t%p  %s\n", (void *)uid_addr, name ? name : missing);
 
 		if (name) {
 			free(name);