[dm-devel] [PATCH] libmultipath: free pp if store_path fails in disassemble_map

[Zhiqiang Liu]

On 2020/7/23 21:22, Benjamin Marzinski wrote:
> On Thu, Jul 23, 2020 at 09:28:51AM +0800, Zhiqiang Liu wrote:
>>
>>
>> On 2020/7/23 4:53, Benjamin Marzinski wrote:
>>> On Wed, Jul 22, 2020 at 04:41:28PM +0800, Zhiqiang Liu wrote:
>>>> In disassemble_map func, one pp will be allocated and stored in pathvec
>>>> (only in client mode) and pgp->paths. However, if store_path fails, pp
>>>> will not be freed, then memory leak problem occurs.
>>>>
>>>> Here, we will call free_path to free pp when store_path fails.
>>>>
>>>
>>> Reviewed-by: Benjamin Marzinski <bmarzins at redhat.com>
>>>
>>> However, this will need to get reworked on top of Martin's patches (or
>>> incorporated into his next verion patchset).
>>>
>>
>> Thanks for your suggestion.
>> Which branch should I choose to modify my patch?
> 
> Martin's latest set of commits is available here:
> https://github.com/mwilck/multipath-tools/tree/ups/submit-2007
> 
>>
>>
Thanks for your patience.
I will send the V2 patch based on the branch: ups/submit-2007.

>>> -Ben
>>>
>>>> Signed-off-by: Zhiqiang Liu <liuzhiqiang26 at huawei.com>
>>>> Signed-off-by: lixiaokeng <lixiaokeng at huawei.com>
>>>> ---
>>>>  libmultipath/dmparser.c | 15 +++++++++++++--
>>>>  1 file changed, 13 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/libmultipath/dmparser.c b/libmultipath/dmparser.c
>>>> index 6225838b..3dc77242 100644
>>>> --- a/libmultipath/dmparser.c
>>>> +++ b/libmultipath/dmparser.c
>>>> @@ -142,6 +142,7 @@ int disassemble_map(vector pathvec, char *params, struct multipath *mpp,
>>>>  	int def_minio = 0;
>>>>  	struct path * pp;
>>>>  	struct pathgroup * pgp;
>>>> +	int pp_need_free_flag = 0;
>>>>
>>>>  	p = params;
>>>>
>>>> @@ -293,6 +294,7 @@ int disassemble_map(vector pathvec, char *params, struct multipath *mpp,
>>>>  			char devname[FILE_NAME_SIZE];
>>>>
>>>>  			pp = NULL;
>>>> +			pp_need_free_flag = 0;
>>>>  			p += get_word(p, &word);
>>>>
>>>>  			if (!word)
>>>> @@ -323,9 +325,15 @@ int disassemble_map(vector pathvec, char *params, struct multipath *mpp,
>>>>  					strncpy(pp->wwid, mpp->wwid,
>>>>  						WWID_SIZE - 1);
>>>>  				}
>>>> +
>>>> +				if (is_daemon)
>>>> +					pp_need_free_flag = 1;
>>>> +
>>>>  				/* Only call this in multipath client mode */
>>>> -				if (!is_daemon && store_path(pathvec, pp))
>>>> +				if (!is_daemon && store_path(pathvec, pp)) {
>>>> +					free_path(pp);
>>>>  					goto out1;
>>>> +				}
>>>>  			} else {
>>>>  				if (!strlen(pp->wwid) &&
>>>>  				    strlen(mpp->wwid))
>>>> @@ -334,8 +342,11 @@ int disassemble_map(vector pathvec, char *params, struct multipath *mpp,
>>>>  			}
>>>>  			FREE(word);
>>>>
>>>> -			if (store_path(pgp->paths, pp))
>>>> +			if (store_path(pgp->paths, pp)) {
>>>> +				if (pp_need_free_flag)
>>>> +					free_path(pp);
>>>>  				goto out;
>>>> +			}
>>>>
>>>>  			/*
>>>>  			 * Update wwid for multipaths which are not setup
>>>> -- 
>>>> 2.24.0.windows.2
>>>>
>>>
>>>
>>> .
>>>
> 
> 
> .
>