dyndbg: fix parsing file query without a line-range suffix

BugLink: https://bugs.launchpad.net/bugs/1928857

commit 7b1ae24 upstream.

Query like 'file tcp_input.c line 1234 +p' was broken by
commit aaebe32 ("dyndbg: accept 'file foo.c:func1' and 'file
foo.c:10-100'") because a file name without a ':' now makes the loop in
ddebug_parse_query() exits early before parsing the 'line 1234' part.
As a result, all pr_debug() in tcp_input.c will be enabled, instead of only
the one on line 1234.  Changing 'break' to 'continue' fixes this.

Fixes: aaebe32 ("dyndbg: accept 'file foo.c:func1' and 'file foo.c:10-100'")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Shuo Chen <shuochen@google.com>
Acked-by: Jason Baron <jbaron@akamai.com>
Link: https://lore.kernel.org/r/20210414212400.2927281-1-giantchen@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

lib/dynamic_debug.c

@@ -396,7 +396,7 @@ static int ddebug_parse_query(char *words[], int nwords,
 			/* tail :$info is function or line-range */
 			fline = strchr(query->filename, ':');
 			if (!fline)
-				break;
+				continue;
 			*fline++ = '\0';
 			if (isalpha(*fline) || *fline == '*' || *fline == '?') {
 				/* take as function name */