mbuf: check shared memory before dumping dynamic space

[ upstream commit d4902ed ]

Because mbuf dyn shared memory was allocated runtime, so it's
necessary to check validity when dump mbuf dyn info.

Also this patch adds an error logging when init shared memory fail.

Fixes: 4958ca3 ("mbuf: support dynamic fields and flags")

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>

lib/librte_mbuf/rte_mbuf_dyn.c

@@ -115,8 +115,10 @@ init_shared_mem(void)
 	} else {
 		mz = rte_memzone_lookup(RTE_MBUF_DYN_MZNAME);
 	}
-	if (mz == NULL)
+	if (mz == NULL) {
+		RTE_LOG(ERR, MBUF, "Failed to get mbuf dyn shared memory\n");
 		return -1;
+	}
 
 	shm = mz->addr;
 
@@ -525,7 +527,11 @@ void rte_mbuf_dyn_dump(FILE *out)
 	size_t i;
 
 	rte_mcfg_tailq_write_lock();
-	init_shared_mem();
+	if (init_shared_mem() < 0) {
+		rte_mcfg_tailq_write_unlock();
+		return;
+	}
+
 	fprintf(out, "Reserved fields:\n");
 	mbuf_dynfield_list = RTE_TAILQ_CAST(
 		mbuf_dynfield_tailq.head, mbuf_dynfield_list);