From: Bui Quang Minh minhquangbui99@gmail.com
[ Upstream commit 6183f4d3a0a2ad230511987c6c362ca43ec0055f ]
On 32-bit architecture, roundup_pow_of_two() can return 0 when the argument has upper most bit set due to resulting 1UL << 32. Add a check for this case.
Fixes: d5a3b1f69186 ("bpf: introduce BPF_MAP_TYPE_STACK_TRACE") Signed-off-by: Bui Quang Minh minhquangbui99@gmail.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Link: https://lore.kernel.org/bpf/20210127063653.3576-1-minhquangbui99@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/stackmap.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 06065fa271241..6e83bf8c080db 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -116,6 +116,8 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
/* hash table size must be power of 2 */ n_buckets = roundup_pow_of_two(attr->max_entries); + if (!n_buckets) + return ERR_PTR(-E2BIG);
cost = n_buckets * sizeof(struct stack_map_bucket *) + sizeof(*smap); cost += n_buckets * (value_size + sizeof(struct stack_map_bucket));