[PATCH net 3/3] bpf: do not test for PCPU_MIN_UNIT_SIZE before percpu allocations
From: Daniel Borkmann <daniel@iogearbox.net>
Date: 2017-10-17 14:56:32
Also in:
lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
PCPU_MIN_UNIT_SIZE is an implementation detail of the percpu allocator. Given we support __GFP_NOWARN now, lets just let the allocation request fail naturally instead. The two call sites from BPF mistakenly assumed __GFP_NOWARN would work, so no changes needed to their actual __alloc_percpu_gfp() calls which use the flag already. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> --- kernel/bpf/arraymap.c | 2 +- kernel/bpf/hashtab.c | 4 ---- 2 files changed, 1 insertion(+), 5 deletions(-)
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 98c0f00..e263673 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c@@ -98,7 +98,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr) array_size += (u64) attr->max_entries * elem_size * num_possible_cpus(); if (array_size >= U32_MAX - PAGE_SIZE || - elem_size > PCPU_MIN_UNIT_SIZE || bpf_array_alloc_percpu(array)) { + bpf_array_alloc_percpu(array)) { bpf_map_area_free(array); return ERR_PTR(-ENOMEM); }
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 431126f..6533f08 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c@@ -317,10 +317,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) */ goto free_htab; - if (percpu && round_up(htab->map.value_size, 8) > PCPU_MIN_UNIT_SIZE) - /* make sure the size for pcpu_alloc() is reasonable */ - goto free_htab; - htab->elem_size = sizeof(struct htab_elem) + round_up(htab->map.key_size, 8); if (percpu)
--
1.9.3