On 11/13/2013 11:43 AM, Sumit Bose wrote:
On Tue, Nov 12, 2013 at 01:42:32PM +0100, Pavel Březina wrote:
> On 11/12/2013 10:03 AM, Sumit Bose wrote:
>> On Mon, Nov 11, 2013 at 12:50:54PM +0100, Pavel Březina wrote:
>>
>>> From f9f6e1ce452f9dc507c4779e6ff74aea412e9457 Mon Sep 17 00:00:00 2001
>>> From: =?UTF-8?q?Pavel=20B=C5=99ezina?= <pbrezina(a)redhat.com>
>>> Date: Mon, 11 Nov 2013 12:47:53 +0100
>>> Subject: [PATCH] pac: fix double free
>>>
>>> ---
>>> src/responder/pac/pacsrv_utils.c | 14 ++++++--------
>>> 1 file changed, 6 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/src/responder/pac/pacsrv_utils.c
b/src/responder/pac/pacsrv_utils.c
>>> index
30055a1345b7d943e6adf822438263c92e53b51a..8380247b10c74d8acabec8e1a8c22944aab38320 100644
>>> --- a/src/responder/pac/pacsrv_utils.c
>>> +++ b/src/responder/pac/pacsrv_utils.c
>>> @@ -74,6 +74,7 @@ errno_t get_sids_from_pac(TALLOC_CTX *mem_ctx,
>>> struct sss_domain_info *user_dom;
>>> struct sss_domain_info *group_dom;
>>> char *sid_str = NULL;
>>> + char *msid_str = NULL;
>>> char *user_dom_sid_str = NULL;
>>> size_t user_dom_sid_str_len;
>>> enum idmap_error_code err;
>>> @@ -231,24 +232,22 @@ errno_t get_sids_from_pac(TALLOC_CTX *mem_ctx,
>>>
>>> }
>>>
>>> - talloc_zfree(sid_str);
>>> -
>>> for(s = 0; s < info3->sidcount; s++) {
>>> err = sss_idmap_smb_sid_to_sid(pac_ctx->idmap_ctx,
info3->sids[s].sid,
>>> - &sid_str);
>>> + &msid_str);
>>> if (err != IDMAP_SUCCESS) {
>>> DEBUG(SSSDBG_OP_FAILURE, ("sss_idmap_smb_sid_to_sid
failed.\n"));
>>> ret = EFAULT;
>>> goto done;
>>> }
>>>
>>> - key.str = sid_str;
>>> + key.str = msid_str;
>>> value.ul = 0;
>>>
>>> - ret = responder_get_domain_by_id(pac_ctx->rctx, sid_str,
&group_dom);
>>> + ret = responder_get_domain_by_id(pac_ctx->rctx, msid_str,
&group_dom);
>>> if (ret == EOK) {
>>> ret = sysdb_search_object_by_sid(mem_ctx, group_dom->sysdb,
>>> - group_dom, sid_str, NULL,
&msg);
>>> + group_dom, msid_str, NULL,
&msg);
>>> if (ret == EOK && msg->count == 1 ) {
>>> value.ul = ldb_msg_find_attr_as_uint64(msg->msgs[0],
>>> SYSDB_GIDNUM, 0);
>>> @@ -263,14 +262,13 @@ errno_t get_sids_from_pac(TALLOC_CTX *mem_ctx,
>>> ret = EIO;
>>> goto done;
>>> }
>>> -
>>> - sss_idmap_free_sid(pac_ctx->idmap_ctx, sid_str);
>>
>> I think this should be replaced by
>>
>> sss_idmap_free_sid(pac_ctx->idmap_ctx, msid_str);
>> msid_str = NULL;
>>
>> otherwise only the last allocated msid_str will be freed in the done
>> section.
There is no change in first patch related to this ^^^ comment.
Sorry, I overlooked it. It turned out that it is even more tricky, since
msid_str is inserted into a hash table that is returned via output
parameter so it should not be freed at all.
I stealed it on sid_table instead of freeing it now.
bye,
Sumit
>>
>>> }
>>>
>>> ret = EOK;
>>>
>>> done:
>>> talloc_free(sid_str);
>>> + sss_idmap_free_sid(pac_ctx->idmap_ctx, msid_str);
>>> sss_idmap_free_sid(pac_ctx->idmap_ctx, user_dom_sid_str);
>>>
>>> if (ret == EOK) {
>>> --
>>> 1.7.11.7
>>>
>>
>> While looking at the code I think there is a potential memory leak in
>> this section as well:
>>
>> ret = responder_get_domain_by_id(pac_ctx->rctx, sid_str,
&group_dom);
>> if (ret == EOK) {
>> ret = sysdb_search_object_by_sid(mem_ctx, group_dom->sysdb,
>> group_dom, sid_str, NULL,
&msg);
>> if (ret == EOK && msg->count == 1 ) {
>> value.ul = ldb_msg_find_attr_as_uint64(msg->msgs[0],
>> SYSDB_GIDNUM, 0);
>> talloc_free(msg);
>> }
>> }
>>
>> while msg should not be set if ret != EOK it will certainly be set if
>> msg->count != 1. Although it should never happen would you mind to
>> remove the talloc_free(msg) out of the if block and add a
>> talloc_zfree(msg) after the if block?
>
> Nice catch. Patches are attached.
>
>
>
_______________________________________________
sssd-devel mailing list
sssd-devel(a)lists.fedorahosted.org
https://lists.fedorahosted.org/mailman/listinfo/sssd-devel