From e804587ecdcde138ab2d4394ba3cd5ac5efaea3b Mon Sep 17 00:00:00 2001 From: Yuntao Wang Date: Tue, 14 Jun 2022 22:26:22 +0800 Subject: [PATCH] bpf: Fix incorrect memory charge cost calculation in stack_map_alloc() commit b45043192b3e481304062938a6561da2ceea46a6 upstream. This is a backport of the original upstream patch for 5.4/5.10. The original upstream patch has been applied to 5.4/5.10 branches, which simply removed the line: cost += n_buckets * (value_size + sizeof(struct stack_map_bucket)); This is correct for upstream branch but incorrect for 5.4/5.10 branches, as the 5.4/5.10 branches do not have the commit 370868107bf6 ("bpf: Eliminate rlimit-based memory accounting for stackmap maps"), so the bpf_map_charge_init() function has not been removed. Currently the bpf_map_charge_init() function in 5.4/5.10 branches takes a wrong memory charge cost, the attr->max_entries * (sizeof(struct stack_map_bucket) + (u64)value_size)) part is missing, let's fix it. Cc: # 5.4.y Cc: # 5.10.y Signed-off-by: Yuntao Wang Signed-off-by: Greg Kroah-Hartman --- kernel/bpf/stackmap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 768ffd603787..811071c227f1 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -117,7 +117,8 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr) return ERR_PTR(-E2BIG); cost = n_buckets * sizeof(struct stack_map_bucket *) + sizeof(*smap); - err = bpf_map_charge_init(&mem, cost); + err = bpf_map_charge_init(&mem, cost + attr->max_entries * + (sizeof(struct stack_map_bucket) + (u64)value_size)); if (err) return ERR_PTR(err);