6.1-stable review patch. If anyone has any objections, please let me know.
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From: Martin KaFai Lau martin.lau@kernel.org
[ Upstream commit 552d42a356ebf78df9d2f4b73e077d2459966fac ]
'struct bpf_local_storage_elem' has an unused 56 byte padding at the end due to struct's cache-line alignment requirement. This padding space is overlapped by storage value contents, so if we use sizeof() to calculate the total size, we overinflate it by 56 bytes. Use offsetof() instead to calculate more exact memory use.
Signed-off-by: Martin KaFai Lau martin.lau@kernel.org Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Yonghong Song yhs@fb.com Acked-by: Andrii Nakryiko andrii@kernel.org Link: https://lore.kernel.org/bpf/20221221013036.3427431-1-martin.lau@linux.dev Stable-dep-of: af253aef183a ("bpf: fix order of args in call to bpf_map_kvcalloc") Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/bpf_local_storage.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c index b1090a2b02b34..f8dd7c516e320 100644 --- a/kernel/bpf/bpf_local_storage.c +++ b/kernel/bpf/bpf_local_storage.c @@ -580,8 +580,8 @@ static struct bpf_local_storage_map *__bpf_local_storage_map_alloc(union bpf_att raw_spin_lock_init(&smap->buckets[i].lock); }
- smap->elem_size = - sizeof(struct bpf_local_storage_elem) + attr->value_size; + smap->elem_size = offsetof(struct bpf_local_storage_elem, + sdata.data[attr->value_size]);
return smap; }