Re: [PATCH bpf 1/2] bpf: Do not copy spin lock field from user in bpf_selem_alloc

On Mon, Nov 14, 2022 at 5:31 AM Xu Kuohai xukuohai@huawei.com wrote:

bpf_selem_alloc function is used by inode_storage, sk_storage and task_storage maps to set map value, for these map types, there may be a spin lock in the map value, so if we use memcpy to copy the whole map value from user, the spin lock field may be initialized incorrectly.

Since the spin lock field is zeroed by kzalloc, call copy_map_value instead of memcpy to skip copying the spin lock field to fix it.

Fixes: 6ac99e8f23d4 ("bpf: Introduce bpf sk local storage")

The tag is wrong. When local storage was introduced it was not possible to use spin_locks there. Pls resubmit.