diff options
| author | Eric Dumazet <edumazet@google.com> | 2021-05-06 05:53:50 -0700 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2021-05-07 10:01:39 +0200 |
| commit | 6c8774a94e6ad26f29ef103c8671f55c255c6201 (patch) | |
| tree | 1a14a9f80a7ed0347b7f1a7f3c51b12d5404f4e1 | |
| parent | a54754ec9891830ba548e2010c889e3c8146e449 (diff) | |
| download | linux-6c8774a94e6ad26f29ef103c8671f55c255c6201.tar.gz | |
netfilter: nftables: avoid potential overflows on 32bit arches
User space could ask for very large hash tables, we need to make sure
our size computations wont overflow.
nf_tables_newset() needs to double check the u64 size
will fit into size_t field.
Fixes: 0ed6389c483d ("netfilter: nf_tables: rename set implementations")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | net/netfilter/nf_tables_api.c | 7 | ||||
| -rw-r--r-- | net/netfilter/nft_set_hash.c | 10 |
2 files changed, 10 insertions, 7 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 926da6ed8d512b..d63d2d8f769c3a 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -4184,6 +4184,7 @@ static int nf_tables_newset(struct sk_buff *skb, const struct nfnl_info *info, unsigned char *udata; struct nft_set *set; struct nft_ctx ctx; + size_t alloc_size; u64 timeout; char *name; int err, i; @@ -4329,8 +4330,10 @@ static int nf_tables_newset(struct sk_buff *skb, const struct nfnl_info *info, size = 0; if (ops->privsize != NULL) size = ops->privsize(nla, &desc); - - set = kvzalloc(sizeof(*set) + size + udlen, GFP_KERNEL); + alloc_size = sizeof(*set) + size + udlen; + if (alloc_size < size) + return -ENOMEM; + set = kvzalloc(alloc_size, GFP_KERNEL); if (!set) return -ENOMEM; diff --git a/net/netfilter/nft_set_hash.c b/net/netfilter/nft_set_hash.c index 328f2ce32e4cbd..7b3d0a78c56967 100644 --- a/net/netfilter/nft_set_hash.c +++ b/net/netfilter/nft_set_hash.c @@ -623,7 +623,7 @@ static u64 nft_hash_privsize(const struct nlattr * const nla[], const struct nft_set_desc *desc) { return sizeof(struct nft_hash) + - nft_hash_buckets(desc->size) * sizeof(struct hlist_head); + (u64)nft_hash_buckets(desc->size) * sizeof(struct hlist_head); } static int nft_hash_init(const struct nft_set *set, @@ -663,8 +663,8 @@ static bool nft_hash_estimate(const struct nft_set_desc *desc, u32 features, return false; est->size = sizeof(struct nft_hash) + - nft_hash_buckets(desc->size) * sizeof(struct hlist_head) + - desc->size * sizeof(struct nft_hash_elem); + (u64)nft_hash_buckets(desc->size) * sizeof(struct hlist_head) + + (u64)desc->size * sizeof(struct nft_hash_elem); est->lookup = NFT_SET_CLASS_O_1; est->space = NFT_SET_CLASS_O_N; @@ -681,8 +681,8 @@ static bool nft_hash_fast_estimate(const struct nft_set_desc *desc, u32 features return false; est->size = sizeof(struct nft_hash) + - nft_hash_buckets(desc->size) * sizeof(struct hlist_head) + - desc->size * sizeof(struct nft_hash_elem); + (u64)nft_hash_buckets(desc->size) * sizeof(struct hlist_head) + + (u64)desc->size * sizeof(struct nft_hash_elem); est->lookup = NFT_SET_CLASS_O_1; est->space = NFT_SET_CLASS_O_N; |