lpm: fix depth small entry add

When adding a "depth small" entry, if its extended flag is not set and
its depth is smaller than the one in the tbl24, nothing should be done
otherwise will operate on the wrong memory area.

Signed-off-by: Zhe Tao <zhe.tao@intel.com>
Acked-by: Cunming Liang <cunming.liang@intel.com>

diff --git a/lib/librte_lpm/rte_lpm.c b/lib/librte_lpm/rte_lpm.c
index de053078d708eebba4e8315b2b8386a0e051a111..163ba3c1730b622076c0514bf44179440deca053 100644 (file)
--- a/lib/librte_lpm/rte_lpm.c
+++ b/lib/librte_lpm/rte_lpm.c
@@ -442,35 +442,41 @@ add_depth_small(struct rte_lpm *lpm, uint32_t ip, uint8_t depth,
                        };
 
                        /* Setting tbl24 entry in one go to avoid race
-                        * conditions */
+                        * conditions
+                        */
                        lpm->tbl24[i] = new_tbl24_entry;
 
                        continue;
                }
 
-               /* If tbl24 entry is valid and extended calculate the index
-                * into tbl8. */
-               tbl8_index = lpm->tbl24[i].tbl8_gindex *
-                               RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
-               tbl8_group_end = tbl8_index + RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
-
-               for (j = tbl8_index; j < tbl8_group_end; j++) {
-                       if (!lpm->tbl8[j].valid ||
-                                       lpm->tbl8[j].depth <= depth) {
-                               struct rte_lpm_tbl8_entry new_tbl8_entry = {
-                                       .valid = VALID,
-                                       .valid_group = VALID,
-                                       .depth = depth,
-                                       .next_hop = next_hop,
-                               };
-
-                               /*
-                                * Setting tbl8 entry in one go to avoid race
-                                * conditions
-                                */
-                               lpm->tbl8[j] = new_tbl8_entry;
-
-                               continue;
+               if (lpm->tbl24[i].ext_entry == 1) {
+                       /* If tbl24 entry is valid and extended calculate the
+                        *  index into tbl8.
+                        */
+                       tbl8_index = lpm->tbl24[i].tbl8_gindex *
+                                       RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+                       tbl8_group_end = tbl8_index +
+                                       RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+
+                       for (j = tbl8_index; j < tbl8_group_end; j++) {
+                               if (!lpm->tbl8[j].valid ||
+                                               lpm->tbl8[j].depth <= depth) {
+                                       struct rte_lpm_tbl8_entry
+                                               new_tbl8_entry = {
+                                               .valid = VALID,
+                                               .valid_group = VALID,
+                                               .depth = depth,
+                                               .next_hop = next_hop,
+                                       };
+
+                                       /*
+                                        * Setting tbl8 entry in one go to avoid
+                                        * race conditions
+                                        */
+                                       lpm->tbl8[j] = new_tbl8_entry;
+
+                                       continue;
+                               }
                        }
                }
        }