On 3/3/21 7:03 AM, Jarkko Sakkinen wrote:
> If sgx_page_cache_init() fails in the middle, a trivial return
> statement causes unused memory and virtual address space reserved for
> the EPC section, not freed. Fix this by using the same rollback, as
> when sgx_page_reclaimer_init() fails.
...
> @@ -708,8 +708,10 @@ static int __init sgx_init(void)
> if (!cpu_feature_enabled(X86_FEATURE_SGX))
> return -ENODEV;
>
> - if (!sgx_page_cache_init())
> - return -ENOMEM;
> + if (!sgx_page_cache_init()) {
> + ret = -ENOMEM;
> + goto err_page_cache;
> + }
Currently, the only way sgx_page_cache_init() can fail is in the case
that there are no sections:
if (!sgx_nr_epc_sections) {
pr_err("There are zero EPC sections.\n");
return false;
}
That only happened if all sgx_setup_epc_section() calls failed.
sgx_setup_epc_section() never both allocates memory with vmalloc for
section->pages *and* fails. If sgx_setup_epc_section() has a successful
memremap() but a failed vmalloc(), it cleans up with memunmap().
In other words, I see how this _looks_ like a memory leak from
sgx_init(), but I don't see an actual leak in practice.
Am I missing something?
