[PATCH v2 3/3] dyndbg: fix problem parsing format="foo bar"

From: Jim Cromie
Date: Tue Aug 25 2020 - 13:34:15 EST


14775b049642 dyndbg: accept query terms like file=bar and module=foo

That commit broke on a tokenization modality where a word could start
with a quote, but couldnt continue with one. So the above would
tokenize as 'format="foo' and 'bar"', and fail hard.

This commit fixes the tokenizer by terminating an unquoted token on
the '=', avoiding that problem. And since ddebug-parse-query will
never see a combined 'keyword=value', revert those parts of the
previous commit.

Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>
---
lib/dynamic_debug.c | 33 ++++++++++++++-------------------
1 file changed, 14 insertions(+), 19 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index a23b5d153153..04b851117eeb 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -237,6 +237,7 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
{
int nwords = 0;

+ vpr_info("entry, buf:'%s'\n", buf);
while (*buf) {
char *end;

@@ -247,6 +248,8 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
if (*buf == '#')
break; /* token starts comment, skip rest of line */

+ vpr_info("start-of-word:%d '%s'\n", nwords, buf);
+
/* find `end' of word, whitespace separated or quoted */
if (*buf == '"' || *buf == '\'') {
int quote = *buf++;
@@ -257,7 +260,9 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
return -EINVAL; /* unclosed quote */
}
} else {
- for (end = buf; *end && !isspace(*end); end++)
+ for (end = buf;
+ *end && *end != '=' && !isspace(*end);
+ end++)
;
BUG_ON(end == buf);
}
@@ -373,30 +378,20 @@ static int ddebug_parse_query(char *words[], int nwords,
unsigned int i;
int rc = 0;
char *fline;
- char *keyword, *arg;

+ if (nwords % 2 != 0) {
+ pr_err("expecting pairs of match-spec <value>\n");
+ return -EINVAL;
+ }
if (modname)
/* support $modname.dyndbg=<multiple queries> */
query->module = modname;

- for (i = 0; i < nwords; i++) {
- /* accept keyword=arg */
- vpr_info("%d w:%s\n", i, words[i]);
-
- keyword = words[i];
- arg = strchr(keyword, '=');
- if (arg) {
- *arg++ = '\0';
- } else {
- i++; /* next word is arg */
- if (!(i < nwords)) {
- pr_err("missing arg to keyword: %s\n", keyword);
- return -EINVAL;
- }
- arg = words[i];
- }
- vpr_info("%d key:%s arg:%s\n", i, keyword, arg);
+ for (i = 0; i < nwords; i+=2) {
+ char *keyword = words[i];
+ char *arg = words[i+1];

+ vpr_info("key:'%s' arg:'%s'\n", keyword, arg);
if (!strcmp(keyword, "func")) {
rc = check_set(&query->function, arg, "func");
} else if (!strcmp(keyword, "file")) {
--
2.26.2