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

[Greg KH]

On Tue, Aug 25, 2020 at 11:33:39AM -0600, Jim Cromie wrote:
>  14775b049642 dyndbg: accept query terms like file=bar and module=foo
> 

What does that above line mean???

> 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 

Again, a Fixes: tag, and fix up your text above please.

Can you do this and send a v3 of this series and any other pending
dyndbg fixes for 5.9-final?

thanks,

greg k-h

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

[Jim Cromie]

 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 
---
 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 \n");
+   return -EINVAL;
+   }
if (modname)
/* support $modname.dyndbg= */
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(>function, arg, "func");
} else if (!strcmp(keyword, "file")) {
-- 
2.26.2