BUG/MEDIUM: mcli: always realign wrapping buffers before parsing them

Pipelined commands easily result in request buffers to wrap, and the
master-cli parser only deals with linear buffers since it needs contiguous
keywords to look for in a list. As soon as a buffer wraps, some commands
are ignored and the parser is called in loops because the wrapped data
do not leave the buffer.

Let's take the easiest path that's already used at the HTTP layer, we
simply realign the buffer if its input wraps. This rarely happens anyway
(typically once per buffer), remains reasonably cheap and guarantees this
cannot happen anymore.

This needs to be backported as far as 2.0.
This commit is contained in:
Willy Tarreau 2022-01-20 08:47:35 +01:00
parent 6cd93f52e9
commit a4e4d66f70

View File

@ -2278,8 +2278,8 @@ int pcli_find_and_exec_kw(struct stream *s, char **args, int argl, char **errmsg
*/
int pcli_parse_request(struct stream *s, struct channel *req, char **errmsg, int *next_pid)
{
char *str = (char *)ci_head(req);
char *end = (char *)ci_stop(req);
char *str;
char *end;
char *args[MAX_CLI_ARGS + 1]; /* +1 for storing a NULL */
int argl; /* number of args */
char *p;
@ -2290,6 +2290,15 @@ int pcli_parse_request(struct stream *s, struct channel *req, char **errmsg, int
int ret;
int i = 0;
/* we cannot deal with a wrapping buffer, so let's take care of this
* first.
*/
if (b_head(&req->buf) + b_data(&req->buf) > b_wrap(&req->buf))
b_slow_realign(&req->buf, trash.area, co_data(req));
str = (char *)ci_head(req);
end = (char *)ci_stop(req);
p = str;
if (!(s->pcli_flags & PCLI_F_PAYLOAD)) {