diff options
| author | Toke Høiland-Jørgensen <toke@redhat.com> | 2020-04-16 10:31:20 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-05-02 17:25:53 +0200 |
| commit | 1fc9f6c1b586ec577a8b4646aedb8c8e8e8aafc8 (patch) | |
| tree | 30cbd0103bef5cf18b57d5048bf7ae3253acdc31 /kernel/bpf | |
| parent | 982c2f3e5cf23a55fe57d2230832daaf5f981edb (diff) | |
cpumap: Avoid warning when CONFIG_DEBUG_PER_CPU_MAPS is enabled
commit bc23d0e3f717ced21fbfacab3ab887d55e5ba367 upstream.
When the kernel is built with CONFIG_DEBUG_PER_CPU_MAPS, the cpumap code
can trigger a spurious warning if CONFIG_CPUMASK_OFFSTACK is also set. This
happens because in this configuration, NR_CPUS can be larger than
nr_cpumask_bits, so the initial check in cpu_map_alloc() is not sufficient
to guard against hitting the warning in cpumask_check().
Fix this by explicitly checking the supplied key against the
nr_cpumask_bits variable before calling cpu_possible().
Fixes: 6710e1126934 ("bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Xiumei Mu <xmu@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200416083120.453718-1-toke@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/cpumap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index 3c18260403dd..61fbcae82f0a 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -455,7 +455,7 @@ static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value, return -EOVERFLOW; /* Make sure CPU is a valid possible cpu */ - if (!cpu_possible(key_cpu)) + if (key_cpu >= nr_cpumask_bits || !cpu_possible(key_cpu)) return -ENODEV; if (qsize == 0) { |