5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pu Lehui <pulehui@xxxxxxxxxx>
This reverts commit 225da02acdc97af01b6bc6ce1a3e5362bf01d3fb which is
commit 281d464a34f540de166cee74b723e97ac2515ec3 upstream.
Commit 225da02acdc9 ("bpf: fix DEVMAP_HASH overflow check on 32-bit
architectures") relies on the v5.11+ base mechanism of memcg-based
memory accounting[0], which is not yet supported on the 5.10 stable
branch, so let's revert this commit in preparation for re-adapting it.
Link: https://lore.kernel.org/bpf/20201201215900.3569844-1-guro@xxxxxx [0]
Signed-off-by: Pu Lehui <pulehui@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/bpf/devmap.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -129,14 +129,13 @@ static int dev_map_init_map(struct bpf_d
bpf_map_init_from_attr(&dtab->map, attr);
if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
- /* hash table size must be power of 2; roundup_pow_of_two() can
- * overflow into UB on 32-bit arches, so check that first
- */
- if (dtab->map.max_entries > 1UL << 31)
- return -EINVAL;
-
dtab->n_buckets = roundup_pow_of_two(dtab->map.max_entries);
+ if (!dtab->n_buckets) /* Overflow check */
+ return -EINVAL;
+ }
+
+ if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
dtab->dev_index_head = dev_map_create_hash(dtab->n_buckets,
dtab->map.numa_node);
if (!dtab->dev_index_head)
