The maximum possible hash parameter name will cause the generated ring names to overlow in snprintf(). Potentially causing conflicting ring names and trouble.
For reference: RTE_MEMPOOL_NAMESIZE = 32 RTE_RING_NAMESIZE = 29 RTE_HASH_NAMESIZE = 32 The hash name is concatenated with a prefix like "HT_RCU_" the hash name string needs to be enforced as having space for the resulting string (ie 22). Since the NAMESIZE's are part of ABI they can't change. Signed-off-by: Stephen Hemminger <[email protected]> --- lib/hash/rte_cuckoo_hash.c | 33 ++++++++++++++++++++++++++------- 1 file changed, 26 insertions(+), 7 deletions(-) diff --git a/lib/hash/rte_cuckoo_hash.c b/lib/hash/rte_cuckoo_hash.c index 2c92c51624..3a521a1a1e 100644 --- a/lib/hash/rte_cuckoo_hash.c +++ b/lib/hash/rte_cuckoo_hash.c @@ -77,6 +77,11 @@ struct __rte_hash_rcu_dq_entry { uint32_t ext_bkt_idx; }; +#define HASH_QSBR_PREFIX "HT_RCU_" +#define HASH_EXT_PREFIX "HT_EXT_" +#define HASH_RING_PREFIX "HT_" + + RTE_EXPORT_SYMBOL(rte_hash_find_existing) struct rte_hash * rte_hash_find_existing(const char *name) @@ -231,6 +236,20 @@ rte_hash_create(const struct rte_hash_parameters *params) return NULL; } + /* + * The API for hash allows 32 characters but maximimu length + * would overflow ring name which is limited to 29 characters (RTE_RING_NAMESIZE). + * To avoid breaking ABI, enforce limit of 25 characters on + * the hash table name. + */ + if (strnlen(params->name, RTE_HASH_NAMESIZE) + > RTE_RING_NAMESIZE - sizeof(HASH_QSBR_PREFIX)) { + rte_errno = EINVAL; + HASH_LOG(ERR, "%s: hash name too long to fit in qsbr ring name", + __func__); + return NULL; + } + /* Check extra flags field to check extra options. */ if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_TRANS_MEM_SUPPORT) hw_trans_mem_support = 1; @@ -272,7 +291,7 @@ rte_hash_create(const struct rte_hash_parameters *params) else num_key_slots = params->entries + 1; - snprintf(ring_name, sizeof(ring_name), "HT_%s", params->name); + snprintf(ring_name, sizeof(ring_name), HASH_RING_PREFIX "%s", params->name); /* Create ring (Dummy slot index is not enqueued) */ r = rte_ring_create_elem(ring_name, sizeof(uint32_t), rte_align32pow2(num_key_slots), params->socket_id, 0); @@ -286,8 +305,8 @@ rte_hash_create(const struct rte_hash_parameters *params) /* Create ring for extendable buckets. */ if (ext_table_support) { - snprintf(ext_ring_name, sizeof(ext_ring_name), "HT_EXT_%s", - params->name); + snprintf(ext_ring_name, sizeof(ext_ring_name), + HASH_EXT_PREFIX "%s", params->name); r_ext = rte_ring_create_elem(ext_ring_name, sizeof(uint32_t), rte_align32pow2(num_buckets + 1), params->socket_id, 0); @@ -299,7 +318,7 @@ rte_hash_create(const struct rte_hash_parameters *params) } } - snprintf(hash_name, sizeof(hash_name), "HT_%s", params->name); + snprintf(hash_name, sizeof(hash_name), HASH_RING_PREFIX "%s", params->name); rte_mcfg_tailq_write_lock(); @@ -1582,7 +1601,8 @@ rte_hash_rcu_qsbr_add(struct rte_hash *h, struct rte_hash_rcu_config *cfg) char rcu_dq_name[RTE_RCU_QSBR_DQ_NAMESIZE]; struct rte_hash_rcu_config *hash_rcu_cfg = NULL; - if (h == NULL || cfg == NULL || cfg->v == NULL) { + if (h == NULL || cfg == NULL || cfg->v == NULL || + strlen(h->name) > RTE_RCU_QSBR_DQ_NAMESIZE - sizeof(HASH_QSBR_PREFIX)) { rte_errno = EINVAL; return 1; } @@ -1606,8 +1626,7 @@ rte_hash_rcu_qsbr_add(struct rte_hash *h, struct rte_hash_rcu_config *cfg) /* No other things to do. */ } else if (cfg->mode == RTE_HASH_QSBR_MODE_DQ) { /* Init QSBR defer queue. */ - snprintf(rcu_dq_name, sizeof(rcu_dq_name), - "HASH_RCU_%s", h->name); + snprintf(rcu_dq_name, sizeof(rcu_dq_name), HASH_QSBR_PREFIX "%s", h->name); params.name = rcu_dq_name; params.size = cfg->dq_size; if (params.size == 0) -- 2.51.0
