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From: Bui Quang Minh <minhquangbui99@gmail.com>
Date: Wed, 27 Jan 2021 06:36:53 +0000
Subject: bpf: Check for integer overflow when using roundup_pow_of_two()
Patch-mainline: v5.11
Git-commit: 6183f4d3a0a2ad230511987c6c362ca43ec0055f
References: bsc#1223035 CVE-2024-26883

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
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 kernel/bpf/stackmap.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -114,6 +114,8 @@ static struct bpf_map *stack_map_alloc(u
 
 	/* 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);
 	if (cost >= U32_MAX - PAGE_SIZE)