From 247a38c52056f3255da357fc6501a1eec414aa23 Mon Sep 17 00:00:00 2001 From: Vladimir Medvedkin Date: Tue, 21 Jan 2020 15:07:09 +0000 Subject: [PATCH] fib: fix possible integer overflow This commit fixes possible integer overflow for prev_idx in build_common_root() CID 350596 and tbl8_idx in write_edge() CID 350597 Unintentional integer overflow (OVERFLOW_BEFORE_WIDEN) overflow_before_widen: Potentially overflowing expression tbl8_idx * 256 with type int (32 bits, signed) is evaluated using 32-bit arithmetic, and then used in a context that expects an expression of type uint64_t (64 bits, unsigned). Coverity issue: 350596, 350597 Fixes: c3e12e0f0354 ("fib: add dataplane algorithm for IPv6") Cc: stable@dpdk.org Signed-off-by: Vladimir Medvedkin --- lib/librte_fib/trie.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/lib/librte_fib/trie.c b/lib/librte_fib/trie.c index 124aa8b98b..2ae2add4f3 100644 --- a/lib/librte_fib/trie.c +++ b/lib/librte_fib/trie.c @@ -240,9 +240,8 @@ tbl8_alloc(struct rte_trie_tbl *dp, uint64_t nh) tbl8_idx = tbl8_get(dp); if (tbl8_idx < 0) return tbl8_idx; - tbl8_ptr = (uint8_t *)dp->tbl8 + - ((tbl8_idx * TRIE_TBL8_GRP_NUM_ENT) << - dp->nh_sz); + tbl8_ptr = get_tbl_p_by_idx(dp->tbl8, + tbl8_idx * TRIE_TBL8_GRP_NUM_ENT, dp->nh_sz); /*Init tbl8 entries with nexthop from tbl24*/ write_to_dp((void *)tbl8_ptr, nh, dp->nh_sz, TRIE_TBL8_GRP_NUM_ENT); @@ -317,7 +316,7 @@ get_idx(const uint8_t *ip, uint32_t prev_idx, int bytes, int first_byte) bitshift = (int8_t)(((first_byte + bytes - 1) - i)*BYTE_SIZE); idx |= ip[i] << bitshift; } - return (prev_idx * 256) + idx; + return (prev_idx * TRIE_TBL8_GRP_NUM_ENT) + idx; } static inline uint64_t @@ -354,8 +353,8 @@ recycle_root_path(struct rte_trie_tbl *dp, const uint8_t *ip_part, return; if (common_tbl8 != 0) { - p = get_tbl_p_by_idx(dp->tbl8, (val >> 1) * 256 + *ip_part, - dp->nh_sz); + p = get_tbl_p_by_idx(dp->tbl8, (val >> 1) * + TRIE_TBL8_GRP_NUM_ENT + *ip_part, dp->nh_sz); recycle_root_path(dp, ip_part + 1, common_tbl8 - 1, p); } tbl8_recycle(dp, prev, val >> 1); @@ -388,7 +387,8 @@ build_common_root(struct rte_trie_tbl *dp, const uint8_t *ip, j = i; cur_tbl = dp->tbl8; } - *tbl = get_tbl_p_by_idx(cur_tbl, prev_idx * 256, dp->nh_sz); + *tbl = get_tbl_p_by_idx(cur_tbl, prev_idx * TRIE_TBL8_GRP_NUM_ENT, + dp->nh_sz); return 0; } @@ -411,8 +411,8 @@ write_edge(struct rte_trie_tbl *dp, const uint8_t *ip_part, uint64_t next_hop, return tbl8_idx; val = (tbl8_idx << 1)|TRIE_EXT_ENT; } - p = get_tbl_p_by_idx(dp->tbl8, (tbl8_idx * 256) + *ip_part, - dp->nh_sz); + p = get_tbl_p_by_idx(dp->tbl8, (tbl8_idx * + TRIE_TBL8_GRP_NUM_ENT) + *ip_part, dp->nh_sz); ret = write_edge(dp, ip_part + 1, next_hop, len - 1, edge, p); if (ret < 0) return ret; @@ -420,8 +420,8 @@ write_edge(struct rte_trie_tbl *dp, const uint8_t *ip_part, uint64_t next_hop, write_to_dp((uint8_t *)p + (1 << dp->nh_sz), next_hop << 1, dp->nh_sz, UINT8_MAX - *ip_part); } else { - write_to_dp(get_tbl_p_by_idx(dp->tbl8, tbl8_idx * 256, - dp->nh_sz), + write_to_dp(get_tbl_p_by_idx(dp->tbl8, tbl8_idx * + TRIE_TBL8_GRP_NUM_ENT, dp->nh_sz), next_hop << 1, dp->nh_sz, *ip_part); } tbl8_recycle(dp, &val, tbl8_idx); -- 2.20.1