Re: [PATCH] bpf: Check for integer overflow when using roundup_pow_of_two()
Hello:
This patch was applied to bpf/bpf.git (refs/heads/master):
On Wed, 27 Jan 2021 06:36:53 + you wrote:
> 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: d5a3b1f ("bpf: introduce BPF_MAP_TYPE_STACK_TRACE")
> Signed-off-by: Bui Quang Minh
>
> [...]
Here is the summary with links:
- bpf: Check for integer overflow when using roundup_pow_of_two()
https://git.kernel.org/bpf/bpf/c/6183f4d3a0a2
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
[PATCH] bpf: Check for integer overflow when using roundup_pow_of_two()
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: d5a3b1f ("bpf: introduce BPF_MAP_TYPE_STACK_TRACE")
Signed-off-by: Bui Quang Minh
---
kernel/bpf/stackmap.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index aea96b638473..bfafbf115bf3 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -115,6 +115,8 @@ 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));
--
2.17.1
