rgw: fix resource leak in rgw_bucket.cc and rgw_user.cc

[scienceluo]

Fix coverity check:

CID 1416847 (#1 of 1): Resource leak (RESOURCE_LEAK)
4. leaked_storage: Variable info going out of scope leaks the storage it points to.

CID 1416844 (#1 of 1): Resource leak (RESOURCE_LEAK)
4. leaked_storage: Variable info going out of scope leaks the storage it points to.

CID 1416843 (#1 of 1): Resource leak (RESOURCE_LEAK)
4. leaked_storage: Variable info going out of scope leaks the storage it points to.

Signed-off-by: Luo Kexue luo.kexue@zte.com.cn

[joscollin]

LGTM.

I have updated the PR URL in Coverity. Please update it by yourself from the next time onwards.

[scienceluo]

Ok, I will update the PR URL in Coverity next time, and thank you for your help. @joscollin

[cbodley]

thanks, good catch! i'm fine with this fix as is it, but we might consider taking it step further with std::unique_ptr:

auto info = ceph::make_unique<list_keys_info>();

...

*phandle = (void *)info.release();

the only advantage here being exception safety in the event that store->list_raw_objects_init() throws

[scienceluo]

@cbodley You mean we can handle it like this:

auto info = ceph::make_unique<list_keys_info>();
...
int ret = store->list_raw_objects_init(store->get_zone_params().domain_root, marker,
                                       &info->ctx);
if (ret < 0) {
  *phandle = (void *)info.release();
  return ret;
}
*phandle = (void *)info;

So that we can handle store->list_raw_objects_init throws safety.
Did I catch the point?

[joscollin]

@cbodley That's a good point. Make it std::unique_ptr and let it delete itself when it goes out of scope / throws / returns.

[joscollin]

*phandle = (void *)info.release();

@scienceluo I think this will again leak.

[scienceluo]

@joscollin So what's the exact way to solve this?

[scienceluo]

@joscollin I found some delete case like this in other functions, maybe we can open another PR to fix this like @cbodley and you said. @joscollin @cbodley what do you think?

[joscollin]

@scienceluo Yes, you can do that. But let's confirm this fix first.

[cbodley]

thanks @scienceluo @joscollin. looks good, but the comments are a bit redundant

edit: build failure from missing #include "common/backport14.h"

[scienceluo]

@cbodley @joscollin Fixed, thanks.

[joscollin]

but the comments are a bit redundant

@cbodley Yes, I have put the comments only to explain the change to @scienceluo.

Sorry for the late response, I was on leave.

[scienceluo]

Close for #17353 instead.