From: Bui Quang Minh minhquangbui99@gmail.com
[ Upstream commit 7dd5d437c258bbf4cc15b35229e5208b87b8b4e0 ]
In 32-bit architecture, the result of sizeof() is a 32-bit integer so the expression becomes the multiplication between 2 32-bit integer which can potentially leads to integer overflow. As a result, bpf_map_area_alloc() allocates less memory than needed.
Fix this by casting 1 operand to u64.
Fixes: 0d2c4f964050 ("bpf: Eliminate rlimit-based memory accounting for sockmap and sockhash maps") Fixes: 99c51064fb06 ("devmap: Use bpf_map_area_alloc() for allocating hash buckets") Fixes: 546ac1ffb70d ("bpf: add devmap, a map for storing net device references") Signed-off-by: Bui Quang Minh minhquangbui99@gmail.com Signed-off-by: Alexei Starovoitov ast@kernel.org Link: https://lore.kernel.org/bpf/20210613143440.71975-1-minhquangbui99@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/devmap.c | 4 ++-- net/core/sock_map.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 85d9d1b72a33..b0ab5b915e6d 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -92,7 +92,7 @@ static struct hlist_head *dev_map_create_hash(unsigned int entries, int i; struct hlist_head *hash;
- hash = bpf_map_area_alloc(entries * sizeof(*hash), numa_node); + hash = bpf_map_area_alloc((u64) entries * sizeof(*hash), numa_node); if (hash != NULL) for (i = 0; i < entries; i++) INIT_HLIST_HEAD(&hash[i]); @@ -143,7 +143,7 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
spin_lock_init(&dtab->index_lock); } else { - dtab->netdev_map = bpf_map_area_alloc(dtab->map.max_entries * + dtab->netdev_map = bpf_map_area_alloc((u64) dtab->map.max_entries * sizeof(struct bpf_dtab_netdev *), dtab->map.numa_node); if (!dtab->netdev_map) diff --git a/net/core/sock_map.c b/net/core/sock_map.c index d758fb83c884..ae62e6f96a95 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -44,7 +44,7 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr) bpf_map_init_from_attr(&stab->map, attr); raw_spin_lock_init(&stab->lock);
- stab->sks = bpf_map_area_alloc(stab->map.max_entries * + stab->sks = bpf_map_area_alloc((u64) stab->map.max_entries * sizeof(struct sock *), stab->map.numa_node); if (!stab->sks) {