From ee35b006ab29669ac0bcefa1fdb6d82e968b0ad7 Mon Sep 17 00:00:00 2001 From: Bui Quang Minh Date: Wed, 27 Jan 2021 06:36:53 +0000 Subject: [PATCH] UPSTREAM: bpf: Check for integer overflow when using roundup_pow_of_two() [ 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") Change-Id: I64adb1eee781d116f9f81f4bad5f38746f6a36ba Signed-off-by: Bui Quang Minh Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20210127063653.3576-1-minhquangbui99@gmail.com Signed-off-by: Sasha Levin --- kernel/bpf/stackmap.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index f8dc89005daa..a8089b0ba356 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -123,6 +123,8 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr) return ERR_PTR(-E2BIG); 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); err = bpf_map_charge_init(&mem, cost + attr->max_entries *