[dpdk-dev] [PATCH v4 1/4] examples/multi_process/client_server_mp: check port validity

[Matan Azrad]

Hi Stephen

From:  Stephen Hemminger
> From: Stephen Hemminger <sthemmin at microsoft.com>
> 
> The mp_server incorrectly allows a port mask that included hidden ports and
> which later caused either lost packets or failed initialization.
> 
> This fixes explicitly checking that each bit in portmask is a valid port before
> using it.
> 
> Fixes: 5b7ba31148a8 ("ethdev: add port ownership")
> Signed-off-by: Stephen Hemminger <sthemmin at microsoft.com>
> ---
>  .../client_server_mp/mp_server/args.c         | 46 +++++++++++++------
>  .../client_server_mp/mp_server/args.h         |  2 +-
>  .../client_server_mp/mp_server/init.c         |  7 +--
>  3 files changed, 35 insertions(+), 20 deletions(-)
> 
> diff --git a/examples/multi_process/client_server_mp/mp_server/args.c
> b/examples/multi_process/client_server_mp/mp_server/args.c
> index b0d8d7665c85..c1ab12ad00d1 100644
> --- a/examples/multi_process/client_server_mp/mp_server/args.c
> +++ b/examples/multi_process/client_server_mp/mp_server/args.c
> @@ -10,6 +10,7 @@
>  #include <errno.h>
> 
>  #include <rte_memory.h>
> +#include <rte_ethdev.h>
>  #include <rte_string_fns.h>
> 
>  #include "common.h"
> @@ -34,6 +35,22 @@ usage(void)
>  	    , progname);
>  }
> 
> +/**
> + * Check if port is present in the system
> + * It maybe owned by a device and should not be used.
> + */
> +static int
> +port_is_present(uint16_t portid)
> +{
> +	uint16_t id;
> +
> +	RTE_ETH_FOREACH_DEV(id) {
> +		if (id == portid)
> +			return 1;
> +	}
> +	return 0;
> +}
> +
>  /**
>   * The ports to be used by the application are passed in
>   * the form of a bitmask. This function parses the bitmask @@ -41,31 +58,32
> @@ usage(void)
>   * array variable
>   */
>  static int
> -parse_portmask(uint8_t max_ports, const char *portmask)
> +parse_portmask(const char *portmask)
>  {
>  	char *end = NULL;
>  	unsigned long pm;
> -	uint16_t count = 0;
> +	uint16_t count;
> 
>  	if (portmask == NULL || *portmask == '\0')
>  		return -1;
> 
>  	/* convert parameter to a number and verify */
>  	pm = strtoul(portmask, &end, 16);
> -	if (end == NULL || *end != '\0' || pm == 0)
> +	if (end == NULL || *end != '\0' || pm > UINT16_MAX || pm == 0)
>  		return -1;
> 
>  	/* loop through bits of the mask and mark ports */
> -	while (pm != 0){
> -		if (pm & 0x01){ /* bit is set in mask, use port */
> -			if (count >= max_ports)
> -				printf("WARNING: requested port %u not
> present"
> -				" - ignoring\n", (unsigned)count);
> -			else
> -			    ports->id[ports->num_ports++] = count;
> +	for (count = 0; pm != 0; pm >>= 1, ++count) {
> +		if ((pm & 0x1) == 0)
> +			continue;
> +
> +		if (!port_is_present(count)) {
> +			printf("WARNING: requested port %u not present -
> ignoring\n",
> +				count);
> +			continue;
>  		}
> -		pm = (pm >> 1);
> -		count++;
> +
> +		ports->id[ports->num_ports++] = count;
>  	}

Why not just to do something like:

RTE_ETH_FOREACH_DEV(id) {
	If (pm & (1 << id)) {
		pm &= ~(1 << id) 
		put in list
	}
}
	If (pm) 
		Warning



>  	return 0;
> @@ -99,7 +117,7 @@ parse_num_clients(const char *clients)
>   * on error.
>   */
>  int
> -parse_app_args(uint16_t max_ports, int argc, char *argv[])
> +parse_app_args(int argc, char *argv[])
>  {
>  	int option_index, opt;
>  	char **argvopt = argv;
> @@ -112,7 +130,7 @@ parse_app_args(uint16_t max_ports, int argc, char
> *argv[])
>  		&option_index)) != EOF){
>  		switch (opt){
>  			case 'p':
> -				if (parse_portmask(max_ports, optarg) != 0){
> +				if (parse_portmask(optarg) != 0) {
>  					usage();
>  					return -1;
>  				}
> diff --git a/examples/multi_process/client_server_mp/mp_server/args.h
> b/examples/multi_process/client_server_mp/mp_server/args.h
> index 79c190a33a37..52c8cc86e6f0 100644
> --- a/examples/multi_process/client_server_mp/mp_server/args.h
> +++ b/examples/multi_process/client_server_mp/mp_server/args.h
> @@ -5,6 +5,6 @@
>  #ifndef _ARGS_H_
>  #define _ARGS_H_
> 
> -int parse_app_args(uint16_t max_ports, int argc, char *argv[]);
> +int parse_app_args(int argc, char *argv[]);
> 
>  #endif /* ifndef _ARGS_H_ */
> diff --git a/examples/multi_process/client_server_mp/mp_server/init.c
> b/examples/multi_process/client_server_mp/mp_server/init.c
> index 3af5dc6994bf..1b0569937b51 100644
> --- a/examples/multi_process/client_server_mp/mp_server/init.c
> +++ b/examples/multi_process/client_server_mp/mp_server/init.c
> @@ -238,7 +238,7 @@ init(int argc, char *argv[])  {
>  	int retval;
>  	const struct rte_memzone *mz;
> -	uint16_t i, total_ports;
> +	uint16_t i;
> 
>  	/* init EAL, parsing EAL args */
>  	retval = rte_eal_init(argc, argv);
> @@ -247,9 +247,6 @@ init(int argc, char *argv[])
>  	argc -= retval;
>  	argv += retval;
> 
> -	/* get total number of ports */
> -	total_ports = rte_eth_dev_count_total();
> -
>  	/* set up array for port data */
>  	mz = rte_memzone_reserve(MZ_PORT_INFO, sizeof(*ports),
>  				rte_socket_id(), NO_FLAGS);
> @@ -259,7 +256,7 @@ init(int argc, char *argv[])
>  	ports = mz->addr;
> 
>  	/* parse additional, application arguments */
> -	retval = parse_app_args(total_ports, argc, argv);
> +	retval = parse_app_args(argc, argv);
>  	if (retval != 0)
>  		return -1;
> 
> --
> 2.20.1