Re: [dpdk-dev] [PATCH v5] linuxapp, eal: Fix the memory leak issue of logid

["Yang, Ziye" <ziye.yang@intel.com>]

Hi Konstantin,

The global logid is used to prevent the memory leak. If we do not do this, but directly free(logid), this pointer will still be used by openlog, which means that we cannot free the logid anymore. And by adding the global variable, it will not only solve the memory leak but also makes the openlog function still work.


Best Regards
Ziye Yang 

-----Original Message-----
From: Ananyev, Konstantin 
Sent: Monday, September 10, 2018 7:55 PM
To: Yang, Ziye <ziye.yang@intel.com>; dev@dpdk.org
Cc: Ziye Yang <optimistyzy@gmail.com>
Subject: RE: [dpdk-dev] [PATCH v5] linuxapp, eal: Fix the memory leak issue of logid

Hi 

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Ziye Yang
> Sent: Wednesday, September 5, 2018 6:39 AM
> To: dev@dpdk.org
> Cc: Ziye Yang <optimistyzy@gmail.com>
> Subject: [dpdk-dev] [PATCH v5] linuxapp, eal: Fix the memory leak 
> issue of logid
> 
> From: Ziye Yang <optimistyzy@gmail.com>
> 
> This patch is used to fix the memory leak issue of logid.
> We use the ASAN test in SPDK when intergrating DPDK and find this 
> memory leak issue.
> 
> Signed-off-by: Ziye Yang <ziye.yang@intel.com>
> ---
>  lib/librte_eal/linuxapp/eal/eal.c     | 21 ++++++++++++++++++++-
>  lib/librte_eal/linuxapp/eal/eal_log.c | 11 ++++++++++-
>  2 files changed, 30 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/librte_eal/linuxapp/eal/eal.c 
> b/lib/librte_eal/linuxapp/eal/eal.c
> index e59ac65..e150200 100644
> --- a/lib/librte_eal/linuxapp/eal/eal.c
> +++ b/lib/librte_eal/linuxapp/eal/eal.c
> @@ -793,7 +793,7 @@ static void rte_eal_init_alert(const char *msg)
>  	int i, fctret, ret;
>  	pthread_t thread_id;
>  	static rte_atomic32_t run_once = RTE_ATOMIC32_INIT(0);
> -	const char *logid;
> +	char *logid;
>  	char cpuset[RTE_CPU_AFFINITY_STR_LEN];
>  	char thread_name[RTE_MAX_THREAD_NAME_LEN];
> 
> @@ -812,6 +812,12 @@ static void rte_eal_init_alert(const char *msg)
> 
>  	logid = strrchr(argv[0], '/');
>  	logid = strdup(logid ? logid + 1: argv[0]);
> +	if (!logid) {
> +		rte_eal_init_alert("Cannot allocate memory for logid\n");
> +		rte_errno = ENOMEM;
> +		rte_atomic32_clear(&run_once);
> +		return -1;
> +	}
> 
>  	thread_id = pthread_self();
> 
> @@ -823,6 +829,8 @@ static void rte_eal_init_alert(const char *msg)
>  	if (rte_eal_cpu_init() < 0) {
>  		rte_eal_init_alert("Cannot detect lcores.");
>  		rte_errno = ENOTSUP;
> +		rte_atomic32_clear(&run_once);
> +		free(logid);
>  		return -1;
>  	}
> 
> @@ -831,6 +839,7 @@ static void rte_eal_init_alert(const char *msg)
>  		rte_eal_init_alert("Invalid 'command line' arguments.");
>  		rte_errno = EINVAL;
>  		rte_atomic32_clear(&run_once);
> +		free(logid);
>  		return -1;
>  	}
> 
> @@ -838,12 +847,14 @@ static void rte_eal_init_alert(const char *msg)
>  		rte_eal_init_alert("Cannot init plugins\n");
>  		rte_errno = EINVAL;
>  		rte_atomic32_clear(&run_once);
> +		free(logid);
>  		return -1;
>  	}
> 
>  	if (eal_option_device_parse()) {
>  		rte_errno = ENODEV;
>  		rte_atomic32_clear(&run_once);
> +		free(logid);
>  		return -1;
>  	}
> 
> @@ -851,6 +862,8 @@ static void rte_eal_init_alert(const char *msg)
> 
>  	if (rte_eal_intr_init() < 0) {
>  		rte_eal_init_alert("Cannot init interrupt-handling thread\n");
> +		rte_atomic32_clear(&run_once);
> +		free(logid);
>  		return -1;
>  	}
> 
> @@ -861,6 +874,8 @@ static void rte_eal_init_alert(const char *msg)
>  		rte_eal_init_alert("failed to init mp channel\n");
>  		if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
>  			rte_errno = EFAULT;
> +			rte_atomic32_clear(&run_once);
> +			free(logid);
>  			return -1;
>  		}
>  	}
> @@ -869,6 +884,7 @@ static void rte_eal_init_alert(const char *msg)
>  		rte_eal_init_alert("Cannot scan the buses for devices\n");
>  		rte_errno = ENODEV;
>  		rte_atomic32_clear(&run_once);
> +		free(logid);
>  		return -1;
>  	}
> 
> @@ -893,6 +909,7 @@ static void rte_eal_init_alert(const char *msg)
>  			rte_eal_init_alert("Cannot get hugepage information.");
>  			rte_errno = EACCES;
>  			rte_atomic32_clear(&run_once);
> +			free(logid);
>  			return -1;
>  		}
>  	}
> @@ -919,8 +936,10 @@ static void rte_eal_init_alert(const char *msg)
>  		rte_eal_init_alert("Cannot init logging.");
>  		rte_errno = ENOMEM;
>  		rte_atomic32_clear(&run_once);
> +		free(logid);
>  		return -1;
>  	}
> +	free(logid);
> 
>  #ifdef VFIO_PRESENT
>  	if (rte_eal_vfio_setup() < 0) {
> diff --git a/lib/librte_eal/linuxapp/eal/eal_log.c 
> b/lib/librte_eal/linuxapp/eal/eal_log.c
> index 9d02ddd..076b1b9 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_log.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_log.c
> @@ -19,6 +19,9 @@
> 
>  #include "eal_private.h"
> 
> +#define DEFAULT_LOG_ID_LEN 128
> +char g_logid[DEFAULT_LOG_ID_LEN];
> +
>  /*
>   * default log function
>   */
> @@ -49,12 +52,18 @@
>  rte_eal_log_init(const char *id, int facility)  {
>  	FILE *log_stream;
> +	int str_len;
> 
>  	log_stream = fopencookie(NULL, "w+", console_log_func);
>  	if (log_stream == NULL)
>  		return -1;
> 
> -	openlog(id, LOG_NDELAY | LOG_PID, facility);
> +	str_len = strlen(id);
> +	if (str_len >= DEFAULT_LOG_ID_LEN)
> +		return -1;
> +
> +	strncpy(g_logid, id, str_len);
> +	openlog(g_logid, LOG_NDELAY | LOG_PID, facility);


Could you explain what is the point here to create a global here and pass pointer to it to openlog()?
Konstantin

> 
>  	eal_log_set_default(log_stream);
> 
> --
> 1.9.3