bpf: lsm: Set bpf_lsm_blob_sizes.lbs_task to 0

bpf task local storage is now using task_struct->bpf_storage, so
bpf_lsm_blob_sizes.lbs_task is no longer needed. Remove it to save some
memory.

Fixes: a10787e ("bpf: Enable task local storage for tracing programs")
Cc: stable@vger.kernel.org
Cc: KP Singh <kpsingh@kernel.org>
Cc: Matt Bobrowski <mattbobrowski@google.com>
Signed-off-by: Song Liu <song@kernel.org>
Acked-by: Matt Bobrowski <mattbobrowski@google.com>
Link: https://lore.kernel.org/r/20240911055508.9588-1-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Author: liu-song-6

security/bpf/hooks.c

@@ -31,7 +31,6 @@ static int __init bpf_lsm_init(void)
 
 struct lsm_blob_sizes bpf_lsm_blob_sizes __ro_after_init = {
 	.lbs_inode = sizeof(struct bpf_storage_blob),
-	.lbs_task = sizeof(struct bpf_storage_blob),
 };
 
 DEFINE_LSM(bpf) = {