[dpdk-dev] [PATCH v2] librte_cmdline: fix parsing initialisation

[Adrien Mazarguil <adrien.mazarguil@6wind.com>]

From: "Bernard.Iremonger" <Bernard.iremonger@intel.com>

The dyn_tokens array is initialised at the beginning of the cmdline_parse
function. However when the inst_num variable is incremented later in the
function the dyn_tokens array is not reinitialised so the tokens from the
previous command are used.

The solution is to initialise the dyn_tokens array in all while (inst)
loops, before calling match_inst().

Fixes: 4fffc05a2b2c ("cmdline: support dynamic tokens")

CC: stable@dpdk.org
Signed-off-by: Bernard Iremonger <bernard.iremonger@intel.com>
Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

---

Nice catch Bernard. This issue can be seen when implementing several
flow-like commands in testpmd.

While testing your original patch though, it appeared that it did not fully
address the issue, as completion remained partially broken. Actually all
match_inst() calls should be preceded by a memset(), so here's an updated
version instead of requesting you to do these changes.
---
 lib/librte_cmdline/cmdline_parse.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/librte_cmdline/cmdline_parse.c b/lib/librte_cmdline/cmdline_parse.c
index b814880..c1d9f23 100644
--- a/lib/librte_cmdline/cmdline_parse.c
+++ b/lib/librte_cmdline/cmdline_parse.c
@@ -276,7 +276,6 @@ cmdline_parse(struct cmdline *cl, const char * buf)
 		return CMDLINE_PARSE_BAD_ARGS;
 
 	ctx = cl->ctx;
-	memset(&dyn_tokens, 0, sizeof(dyn_tokens));
 
 	/*
 	 * - look if the buffer contains at least one line
@@ -321,6 +320,7 @@ cmdline_parse(struct cmdline *cl, const char * buf)
 		debug_printf("INST %d\n", inst_num);
 
 		/* fully parsed */
+		memset(&dyn_tokens, 0, sizeof(dyn_tokens));
 		tok = match_inst(inst, buf, 0, tmp_result.buf,
 				 sizeof(tmp_result.buf), &dyn_tokens);
 
@@ -400,7 +400,6 @@ cmdline_complete(struct cmdline *cl, const char *buf, int *state,
 
 	debug_printf("%s called\n", __func__);
 	memset(&token_hdr, 0, sizeof(token_hdr));
-	memset(&dyn_tokens, 0, sizeof(dyn_tokens));
 
 	/* count the number of complete token to parse */
 	for (i=0 ; buf[i] ; i++) {
@@ -423,6 +422,7 @@ cmdline_complete(struct cmdline *cl, const char *buf, int *state,
 		inst = ctx[inst_num];
 		while (inst) {
 			/* parse the first tokens of the inst */
+			memset(&dyn_tokens, 0, sizeof(dyn_tokens));
 			if (nb_token &&
 			    match_inst(inst, buf, nb_token, NULL, 0,
 				       &dyn_tokens))
@@ -530,6 +530,7 @@ cmdline_complete(struct cmdline *cl, const char *buf, int *state,
 		/* we need to redo it */
 		inst = ctx[inst_num];
 
+		memset(&dyn_tokens, 0, sizeof(dyn_tokens));
 		if (nb_token &&
 		    match_inst(inst, buf, nb_token, NULL, 0, &dyn_tokens))
 			goto next2;
-- 
2.1.4