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

[Ananyev, Konstantin]

> -----Original Message-----
> From: Yang, Ziye
> Sent: Monday, September 10, 2018 12:58 PM
> To: Ananyev, Konstantin <konstantin.ananyev at intel.com>; dev at dpdk.org
> Cc: Ziye Yang <optimistyzy at gmail.com>
> Subject: RE: [dpdk-dev] [PATCH v5] linuxapp, eal: Fix the memory leak issue of logid
> 
> 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.

But then I suppose you can avoid any dynamic memory allocation at all with something like that:
rte_eal_init(int argc, char **argv)
{
   ...
   static char logid[PATH_MAX];
   ...
   const char *p= strrchr(argv[0], '/');
   snprintf(logid, sizeof(logid), "%s", p);
   ...
   rte_eal_log_init(logid, ...);

?
Konstantin

> 
> 
> Best Regards
> Ziye Yang
> 
> -----Original Message-----
> From: Ananyev, Konstantin
> Sent: Monday, September 10, 2018 7:55 PM
> To: Yang, Ziye <ziye.yang at intel.com>; dev at dpdk.org
> Cc: Ziye Yang <optimistyzy at 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 at dpdk.org] On Behalf Of Ziye Yang
> > Sent: Wednesday, September 5, 2018 6:39 AM
> > To: dev at dpdk.org
> > Cc: Ziye Yang <optimistyzy at gmail.com>
> > Subject: [dpdk-dev] [PATCH v5] linuxapp, eal: Fix the memory leak
> > issue of logid
> >
> > From: Ziye Yang <optimistyzy at 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 at 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